bluuebunny/crossref_metadata_2025 huggingface dataset:
On Multiplying Negative Numbers
Authors: Crowley Mary L. , Dunn Kenneth A.
Published: January 2021

Although we might sympathize with Auden's sentiment, we must discuss the question of why a minus times a minus is a plus. From the time the negative numbers are first introduced in school, students are constantly posing this question. Unfortunately, the answers that they receive are not always completely satisfying.
A Question of Coincidences
Authors: Duncan David R. , Litwiller Bonnie H.
Published: January 2021

Suppose Fred rolls a fair hexahedral die ten times consecutively and records the results. As he studies the results, he notices that the seventh and eighth rolls both yielded a six. He regards this occurrence as an interesting coincidence and wonders what the probability of such a coincidence is.
Measuring the Area of Golf Greens and Other Irregular Regions
Authors: Martin W. Gary , Ponte Joao
Published: January 2021

Much attention is now focused on problem solving as an important activity in the mathematics classroom. Problem solving is a central idea in An Agenda for Action (NCTM 1980). One question that may occur to many teachers is, “Where am I supposed to find all these great problems?” In fact, while purely mathematical problems abound, interesting real-life problems are not always so easy to find. Good problems must appear fresh and natural to our students and must tickle their mathematical imaginations. In this article, we examine one such “true life” problem that we have found stimulating.
The Shape of Instruction in Geometry: Some Highlights from Research
Authors: Suydam Marilyn N.
Published: January 2021

Why, what, when, and how is geometry taught most effectively? Researchers have sought answers to many such recurring questions that teachers ask about the teaching of geometry. This article presents brief answers to some of these questions, describing the shape of instruction in geometry.
A Surprising Fact about Pythagorean Triples
Authors: Brown Susan A.
Published: January 2021

Joe Knez, a geometry student at Proviso West, asked me if a relationship he had noticed in his homework would always be true. Part of his assignment was to test numbers to see if they were Pythagorean triples. Joe noticed that whenever he found three numbers that were triples, their product was divisible by 60. If this relationship was always true, it would provide an easy way to eliminate most numbers that are not Pythagorean triples.
Some Little-known Rules and Why They Work
Authors: Schwartzman Steven
Published: January 2021

Old mathematics textbooks included not only topics that are no longer in the curriculum but also familiar topics that were treated in now unfamiliar ways. Whereas the emphasis in today's textbooks is on learning general algorithms and why they work, the old textbooks were often filled with special rules and shortcuts that reduced the amoung of work that students had to do to a minimum. As one illustration of this change in attitude, consider the old square-root algorithm versus the divide- and-average approach found in most recent books: the former is more efficient but harder to understand, whereas the latter is easy to understand but hard to put into practice.
Microcomputer-assisted mathematics: Roots: Newton's Method
Authors: Kimberling Clark
Published: January 2021

Not long after students first meet derivatives, they should learn Newton's method for approximating the roots of functions. Newton's method is surely one of the simplest, cleverest, and most widely used of all the many applications of derivatives.
Teaching Basic Mathematics and Survival Skills
Authors: Frey-Mason Patricia
Published: January 2021

In this age of computers and with the emphasis on the teaching of mathematics, we are apt to forget the needs of our most “basic” students. I define basic students as those aspiring to high school diplomas but not having the ability to succeed in college preparatory mathematics courses. We require these students to pass a year of basic arithmetic, usually called general mathematics, geared toward enabling them to pass a minimum-competency test set up by the state.
A Matter of Disks
Authors: Ewbank William A.
Published: January 2021

The best sort of problem is that which arises naturally in the course of the day, especially if you are not quite sure how to solve it. Perhaps your mathematics class could help you!
Understanding Word Problems
Authors: Stiff Lee V.
Published: January 2021

For several years now, I have been asked to share with junior and senior high school mathematics teachers in North Carolina ways to improve students' reading comprehension of word problems. My work with teachers and students has given me the opportunity to field-test several strategies for improving reading skills. One such strategy uses comprehension guides (Earle 1976; Herber 1978).
Dirichlet Polygons—an Example of Geometry in Geography
Authors: O'Shea Thomas
Published: January 2021

The teaching of geometry in the elementary school can be an exciting experience; children are receptive to experimentation, and many activities can be devised to facilitate learning. Generally, however, the use of exploration in geometry decreases as students progress through school and as they begin the study of formal axiomatic systems. In the higher grades we need to present interesting uses of geometry that will allow students to develop their powers of exploration and problem solving. The purpose of this article is to outline an example of how geometry serves as a model in the real world and to suggest how it might be used at the high school level.
Soundoff: An Integrated Approach for Secondary School Mathematics
Authors: Paul Fredric
Published: January 2021

In 1972, after many years of concern and dissatisfaction with the traditional three-year high school mathematics program of geometry sandwiched between algebra (Math 9) and algebra-trigonometry (Math 11), the Bureau of Mathematics of the New York State Education Department decided to investigate a possible alternative approach. In June of that year, an ad hoc committee of the state's mathematics educators developed an outline for a three-year curriculum aimed at bringing together the various branches of mathematics previously treated as independent, year-long courses. Most of the traditional content was retained, although not necessarily at the same grade level; in addition, probability, statistics, logic, and transformation geometry were included in a three-year comprehensive program.
An Alternative to Precalculus
Authors: Smith Eric S.
Published: January 2021

A definite need arises at the high school level for courses that can be offered as alternatives to precalculus for juniors and seniors. The typical mathematics sequence for the college-bound student offers a sequence of algebra and geometry courses that aims the student toward precalculus or calculus. If the student is not inclined toward following this sequence for one reason or another, few alternatives are then available.
The Contributions of Karaji—Successor to al-Khwarizmi
Authors: Pazwash Hormoz , Mavrigian Gus
Published: January 2021

It is enlightening to notice an increasing number of historical notes on the development of mathematics and to realize their pedagogical value in the classroom (Arndt 1983; Campbell 1977; Flusser 1981; Swetz 1984), Truly, mathematics without historical connotations loses its greatness and realism.
The Mathematics of Wrong Turns
Authors: Cashing Douglas L. , White Albert
Published: January 2021

Have you ever made a wrong turn white traveling in unfamiliar territory? If you are on a schedule, the question arises as to how fast you must now travel to complete the trip as planned. Let's restate this problem in more specific terms, generating one that can provide practice in algebraic manipulation while maintaining a sense of real-world usefulness.
O tempo, o ritmo e o pensamento musical
Authors:   Universidade Federal do Estado do Rio de Janeiro - UNIRIO, Gubernikoff Carole , Lemos Maya Suemi ,   Universidade Estadual do Rio de Janeiro - UERJ
Published: January 2021

Compositores do início do século XX encontraram meios de transcender a rítmica métrica, em formas de abordar a dimensão temporal da música que reverberam experiências rítmicas anteriores à consolidação da métrica e da harmonia tonal. Percorrendo esses momentos históricos da música, revelam-se maneiras pelas quais se entrelaçam no devir histórico o tempo e o pensamento musical. Exemplos de partituras atestam diferentes esforços de transcender a rítmica e a métrica fraseológica.
A Poesia da Música ou a Música da Poesia: a estruturação poética da fraseologia em alguns exemplos de Música Popular do Brasil
Authors:   UNICAMP, Tiné Paulo
Published: January 2021

Este artigo trata de uma proposta no campo da teoria musical através de analogia entre a construção fraseológica musical e a elaboração poética. A metodologia parte dos tópicos de tratados históricos sobre a fraseologia musical e temas filosóficos ligados à poética. Como resultado, através de uma prática analítica e do confronto da fraseologia com regras de poética, chega-se a uma proposta de duas novas categorias fraseológicas. Concluindo, as estruturas fraseológicas de músicas do repertório popular brasileiro poderiam ser entendidas como análogas a certas estruturas poéticas, ensejando-se, desse modo, discussões conceituais derivadas da problemática apresentada.
Experimentação e ressignificação de elementos composicionais do Clube da Esquina no processo de criação de dois arranjos vocais
Authors:   Universidade Federal de Uberlandia, Junior Carlos Roberto Ferreira Menezes , Ramos Marco Antonio da Silva ,   Universidade de São Paulo
Published: January 2021

Este artigo apresenta os resultados das experimentações realizadas no processo de criação de dois arranjos vocais que tiveram como principais alimentadores os elementos composicionais levantados durante o processo de análise estilística dos álbuns fonográficos do grupo de músicos conhecidos pelo termo Clube da Esquina. Assim, visa expor as possibilidades artísticas que podem emergir a partir da exploração da ideia de que a análise estilística também pode se inserir como recurso relevante dentro da dinâmica de apreensão e experimentação dos parâmetros de estruturação musical inerentes ao processo de criação de arranjos para grupos vocais. O primeiro arranjo foi o da canção Milagre dos Peixes, de Milton Nascimento e Fernando Brant, e o segundo da canção Chovendo na Roseira, de Tom Jobim. Por fim, é apresentada uma breve discussão de cunho teórico-reflexivo acerca das possibilidades que tal abordagem pôde oferecer nesta pesquisa e perspectivas sobre processos criativos no âmbito do arranjo vocal de repertório da música popular urbana.
Patrimônio musical bibliográfico na Seção de Obras Raras da Biblioteca Fran Paxeco do Grêmio Literário e Recreativo Português em Belém do Pará: um estudo acerca de memórias e identidades em uma coleção especial
Authors:   UFPA, Duarte Fernando Lacerda Simões
Published: January 2021

Embora menos mencionados no campo da musicologia histórica no Brasil do que os arquivos, os acervos das bibliotecas também contêm fontes de interesse para o estudo da música. Neste trabalho, busca-se compreender a constituição da Seção de Obras Raras da Biblioteca do Grêmio Literário e Recreativo Português do Pará, observando-se indícios que sugiram ou afastem a hipótese de que os itens da seção e, mais especificamente, aqueles de interesse musical – manual de procissões, livros de teoria e libretos encadernados, datados dos séculos XVII e XVIII – tenham tido usos locais ao tempo de sua produção. Para tanto, foi pesquisa de campo no Pará e em Lisboa, recorrendo-se ainda ao quadro teórico de Cataldo e Loureiro, Mouren e Candau. Os resultados apontam para a provável aquisição dos itens bibliográficos no século XIX, que, embora não pareçam ter relação com práticas musicais locais, sua seleção reflete a afirmação intencional de uma identidade luso-amazônida.
Os estudos sobre a história da música em Santa Catarina: um panorama da produção acadêmica à luz da musicologia
Authors:   FURB - Universidade de Blumenau, Pereira Tiago
Published: January 2021

De caráter bibliográfico, com o intuito de compreender a escrita da história da música em Santa Catarina, realiza-se um mapeamento das pesquisas defendidas sobre esse tema, junto aos programas de Pós-Graduação no Brasil. Os trabalhos são problematizados a partir de enfoques específicos, como a perspectiva institucional, biográfica e voltada à descrição de gêneros e movimentos musicais catarinenses. As pesquisas de cunho científico contribuem para a superação de uma literatura musical parcial e exaltativa. Nota-se uma predominância de trabalhos voltados à capital do estado, dentre pesquisas histórico-musicológicas ou de natureza etnográfica, com um gradativo processo de descentralização. Pode-se dizer, por fim, que todos os trabalhos mapeados trazem importantes contribuições para a escrita e para o entendimento da cultura musical catarinense do passado e do presente.
Spencer Noob And The Cannibal Skull Concert, una aventura gráfica
Authors: Agustín Gavaldà Jordi
Published: January 2021

Desarrollo de un videojuego tipo aventura gráfica al estilo clásico de la década de 1990.
Network Analysis of Memoires by Soviet Cosmonautics Creators: Professional Interactions Circle
Authors: Grebenchenko Irina Viktorovna
Published: January 2021

The article studies the interactions of the Chief Designers’ Council members by the network analysis method based on the prosopographic database covering the creators of Soviet cosmonautics. Personal contacts of cosmonautics creators were undoubtedly very important in the activities of senior managers of such a complex scientific and engineering industry as the Soviet cosmonautics was. These are professional relations of the Chief Designers’ Council members the article addresses. The source base of the research is the materials library of the Russian State Archive of scientific and technical documentation, the Russian State Public History Library, the Russian State Archive of scientific and technical documentation, the funds of the Memorial Museum of Cosmonautics and the archive of the Memorial House Museum of academician Sergey Korolev. The research novelty is the goal set to study professional communications of the Soviet space program creators on the basis of network analysis as well as the first attempt to collect and process a large array of texts of biographical and memoir sources (5500 abridged pages) associated with the Chief Designers’ Council using a set of quantitative methods. The main results of this study are networks of interactions that show who of the members of the 1946-1967 Chief Designers’ Council had a significant impact on the development of the Soviet cosmonautics and how communication links were distributed between them.
Digital Technologies and Information Resources to Study Wars and Military Conflicts in the Russian South: Experience and Prospects
Authors: Dmitrieva Natalia Valerievna
Published: January 2021

The article considers the use of digital technologies to study wars and military conflicts in the south of Russia in the 18th – 21st centuries. It analyzes the prerequisites for changing the theoretical and methodological foundations of scientific research addressing the problems indicated. Particular attention is paid to the description of the conceptual approach and the structure of the source database on the history of military clashes in the south of the country. The article provides a list of archives and funds that formed the basis of the database and also contains the description of the possibilities and prospects for its further use for research purposes to select, systematize and group sources. The analysis of information resources, in particular the existing data on memorial culture objects mapping,  made it possible to emphasize the topical necessity to map monuments dedicated to military conflicts in southern Russia. The mapping has been carried out on the basis of the database of Rostov-on-Don and Rostov region’s monuments. Its constituent elements were the information about the restoration work, the source of funding for the monument installation, its physical condition and demand. The introduction of expert interviews as a separate type of sources into the database made it possible to identify the prospects of their content analysis by means of MAXQDA software package.
Examining Testing and Growth Mindset in High School Social Studies Students
Authors: Waters Stewart , Russell William B. , Newport Andrea
Published: January 2021

Testing has been a contested aspect of education for decades. The way in which testing, standardized tests, and student motivations correlate is a separate issue. This action research study investigates the relationship between pre-tests and students’ perception of their personal
growth. Three classes of 11th grade U.S. History were utilized to collect data from a total of 80 students (N=80). Participants completed one pre-test every two weeks throughout the semester. At the end of the semester, students completed a questionnaire to examine their perceptions of frequent
pre-testing, and of whether assessments influenced their learning and personal growth. The researchers sought to examine if interim testing impacted student motivation towards standardized testing in a social studies classroom.
Dança Cristal: da arte do movimento à abordagem somático-performativa
Authors: Fernandes Ciane
Published: January 2021

O livro traça o desenvolvimento da Abordagem Somático-Performativa de pesquisa em artes cênicas, a partir de uma perspectiva autobiográfica, simultaneamente acadêmica e poética, analítica e criativa. A abordagem inédita no país, faz parte do terceiro paradigma metodológico, integrando o arcabouço da Prática Artística como Pesquisa, que vem sendo desenvolvido principalmente na Austrália, Escandinávia e Inglaterra, apresentadas na obra num entrelaçamento de criação interartística fundamentada na corporeidade e reflexão teórica transdisciplinar. A Abordagem associa a educação somática e os estudos da performance, fundamentando-se na Análise Laban/Bartenieff de Movimento, no Movimento Autêntico, na dança-teatro e na performance, integrando também questões relativas à improvisação, à dança e diferença (dança inclusiva), à intervenção urbana e à ecoperformance.
Molecular basis for the adaptive evolution of environment-sensing by H-NS proteins
Authors: Zhao Xiaochuan , Shahul Hameed Umar F , Kharchenko Vladlena , Liao Chenyi , Huser Franceline , Remington Jacob M , Radhakrishnan Anand K , Jaremko Mariusz , Jaremko Łukasz , Arold Stefan T , Li Jianing
Published: January 2021

The DNA-binding protein H-NS is a pleiotropic gene regulator in gram-negative bacteria. Through its capacity to sense temperature and other environmental factors, H-NS allows pathogens like Salmonella to adapt their gene expression to their presence inside or outside warm-blooded hosts. To investigate how this sensing mechanism may have evolved to fit different bacterial lifestyles, we compared H-NS orthologs from bacteria that infect humans, plants, and insects, and from bacteria that live on a deep-sea hypothermal vent. The combination of biophysical characterization, high-resolution proton-less nuclear magnetic resonance spectroscopy, and molecular simulations revealed, at an atomistic level, how the same general mechanism was adapted to specific habitats and lifestyles. In particular, we demonstrate how environment-sensing characteristics arise from specifically positioned intra- or intermolecular electrostatic interactions. Our integrative approach clarified the exact modus operandi for H-NS-mediated environmental sensing and suggested that this sensing mechanism resulted from the exaptation of an ancestral protein feature.
Impacts of climate variability on growth and variability of agricultural productivity: a review
Authors: Kumari Rekha , Kanga Shruti
Published: January 2021

In this paper a comprehensive review of different research papers, reports and articles associated with the impacts of the variability of climatic parameters mainly temperature and rainfall on agricultural productivity and its variability. In the high altitude and hilly regions due increase of temperature from low temperature, it makes those regions more favorable to more crop yield. Whereas in the planer region due to the increase of temperature the crop yields are getting affected to a greater extent. The rainfall is also having a great impact on the crop yield. However, due to irregular seasonal patterns, an increase in the number of dry days and extremely high rainy days are affecting the yield of almost every crop. Apart from temperature and rainfall, the crop yields are also affected by greenhouse gases, for example, carbon dioxide, carbon mono-oxide, methane, etc. In opposite to that, the high volume of agricultural practices can decrease the level of greenhouse gases and climate change.
Genetic effects of eelgrass restoration efforts by fishers' seeding to recover seagrass beds as an important natural capital for coastal ecosystem services
Authors: Hori Masakazu , Sato Masaaki
Published: January 2021

The reestablishment of seagrass vegetation is a vital part of recovering coastal marine ecosystem services. Historically the Hinase area was a famous for the fishing by coastal pound netting in eelgrass beds, but this practice was progressively displaced with oyster farming due to an enormous decline in seagrass vegetation. For several decades, the local fishers' cooperative has worked to restore eelgrass beds by a seeding method. Through these efforts, seagrass vegetation in their fishing area has increased to about half of their previous area. This study examined the effect of long‐term seeding by fishers on the recovery of eelgrass beds in the Hinase area, based on analysis of eelgrass genetic structure using microsatellite markers. Specimens for the DNA analysis were collected from each of all eelgrass meadows that the fishers conducted sowing eelgrass seeds as well as from the source sites where they collected the seeds. The results found that restored beds in the study area have high genetic diversity comparable to natural ones. The multiple regression analysis revealed that a combined model of seedling intensity and geographic distance (R2 = .457) better explained genetic structure across our sampling sites than models of seedling intensity (R2 = .092) or geographic distance only (R2 = .344). This supports that the eelgrass seeds they sowed did not disturb the genetic structure but rather supplemented natural dispersal, suggesting that the fishers' seeding did not develop nonnatural seagrass meadows but certainly contributed to the recovery of natural seagrass meadows.
CT imaging of gold nanoparticles in a human‐sized phantom
Authors: Oumano Michael , Russell Liz , Salehjahromi Morteza , Shanshan Lou , Sinha Neeharika , Ngwa Wilfred , Yu Hengyong
Published: January 2021

Introduction

Gold nanoparticles (AuNPs) are visualized and quantified in a human‐sized phantom with a clinical MDCT scanner.

Methods

Experiments were conducted with AuNPs between 0.00171 and 200 mgAu/mL. CT images were acquired at 80, 100, 120, and 140 kVp in a 33‐cm phantom. Image contrast due to AuNPs was experimentally determined from regions of interest (ROIs) and effective linear attenuation coefficients were calculated from CT x‐ray spectra with consideration of tissue attenuation.

Results

The typical 12‐bit dynamic range of CT images was exceeded for AuNPs at 150 mgAu/mL. A threshold concentration of 0.3–1.4 mgAu/mL was determined for human visualization in 1‐mm images at a typical diagnostic CTDIvol of 23.6 mGy. Optimal image contrast was also achieved at 120 kVp and verified by calculation.

Conclusions

We have shown that scanners capable of reconstructing images with extended Hounsfield scales are required for distinguishing any contrast differences above 150 mgAu/mL. We have also shown that AuNPs result in optimal image contrast at 120 kVp in a human‐sized phantom due to gold’s 80.7 keV k‐edge and the attenuation of x‐rays by tissue. Typical CT contrast agents, like iodine, require the use of lower kVps for optimal visualization, but lower kVps are more difficult to implement in the clinic because of elevated noise levels, elongated scan times, and/or beam‐hardening artifacts. This indicates another significant advantage of AuNPs over iodine not yet discussed in the literature.
Description and results of birth defects surveillance and follow‐up programs in Bogotá and Cali, Colombia, 2002–2019
Authors: Zarante Ignacio , Carreño‐Martinez Angie Carolina , Ibañez Lina Maria , Gracia Gloria , Blandón Esperanza , Perez Gladys , Holguín Jorge , Hurtado‐Villa Paula
Published: January 2021

Birth defects are structural or functional defects present at birth and are caused by different factors that affect intrauterine development. They are the second most common cause of death under five years of age in Latin America and the Caribbean. In Bogotá and Cali, Colombia, there are two surveillance programs established to evaluate the prevalence of them. The purpose of the following article is to describe the experience and results of the surveillance of the Birth Defects Surveillance Programs in Bogotá and Cali, Colombia, 2002‐2019. The information was taken from the surveillance programs that have an active hospital system in some institutions of the city (ECLAMC modality), and use data from the passive national system (Sistema Nacional de Vigilancia en Salud Pública ‐ SIVIGILA) to expand their coverage. From 2002 until 2019, 1,289.650 births have been monitored through one of the surveillance programs, including both methodologies. The importance of surveillance programs relies on the amount of data obtained that allows the development of research, the detection of potential changes throughout time, and the guidance of public policies to improve promotion and prevention strategies.
Quantifying dementia prevention potential in the FINGER randomized controlled trial using the LIBRA prevention index
Authors: Deckers Kay , Köhler Sebastian , Ngandu Tiia , Antikainen Riitta , Laatikainen Tiina , Soininen Hilkka , Strandberg Timo , Verhey Frans , Kivipelto Miia , Solomon Alina
Published: January 2021

Introduction

Individuals in early dementia prevention trials may differ in how much they benefit from interventions depending on their initial risk level. Additionally, modifiable dementia risk scores might be used as surrogate/intermediate outcomes.

Methods

In the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER), we investigated in post hoc analyses (N = 1207) whether the cognitive benefits of the 2‐year multi‐domain lifestyle intervention differed by baseline dementia risk measured with the “LIfestyle for BRAin Health” (LIBRA) score. We also investigated intervention effects on change in LIBRA score over time.

Results

Overall, higher baseline LIBRA was related to less cognitive improvement over time. This association did not differ between the intervention and control groups. The intervention was effective in decreasing LIBRA scores over time, regardless of baseline demographics or cognition.

Discussion

The cognitive benefit of the FINGER intervention was similar across individuals with different LIBRA scores at baseline. Furthermore, LIBRA may be useful as a surrogate/intermediate endpoint and surveillance tool to monitor intervention success during trial execution.
The application of Green Lean Six Sigma
Authors: Gholami Hamed , Jamil Norhazrina , Mat Saman Muhamad Zameri , Streimikiene Dalia , Sharif Safian , Zakuan Norhayati
Published: January 2021

Green Lean Six Sigma has been recently clarified to improve the environmental sustainability performance of operations, but it seems glaringly scarce and in need of cutting‐edge studies to integrate the concepts of green, lean, and Six Sigma into one unified application. This paper is accordingly aimed at constituting the application of Green Lean Six Sigma as a cleaner production. In doing so, a Define, Measure, Analyze, Improve, and Control (DMAIC)‐based approach that is one of Six Sigma's well‐known methods was proposed to systematize a Green Lean tool—environmental value stream mapping. Thus, this paper as one of the preliminary studies aligns environmental value stream mapping with DMAIC through presenting the proposed methodological approach, which relies on the five DMAIC phases—Define, Measure, Analyze, Improve, and Control—and considers green wastes in each phase simultaneously. To support the narrow body of knowledge, this proposed approach was validated via the action research‐oriented case study implemented in the substrate manufacturing system that seeks to develop the environmental sustainability of its production processes and subsequently its general competitiveness. The findings indicated the effectiveness of a DMAIC‐based approach in systematizing environmental value stream mapping and improving its efficacy to achieve environmental sustainability. The case analysis revealed that the application can significantly lessen the consumption of chemicals and energy in the system by 28% and 21%, respectively.
Adrenal pheochromocytoma treated by combination of adrenal arterial embolization and radiofrequency ablation
Authors: Kako Yasukazu , Ueki Ryusuke , Yamamoto Shingo , Takaki Haruyuki , Aoki Yoshitaka , Yokoyama Osamu , Yamakado Koichiro
Published: January 2021

Combined therapy with adrenal arterial embolization and RF ablation may represent a useful therapeutic option with curative properties in select patients with pheochromocytoma.
Experimental and numerical investigation of the scale‐up criterion of solid‐viscous fluid mixing in a stirred tank
Authors: Lin Daiqi , Wei Hongyuan , Song Erjia , Ng Boonho , He Ting , Dang Leping
Published: January 2021

The scale‐up of mixing processes is crucial for process engineering and power optimization in the chemical industry. Scale‐up of fluid mixing in stirred systems becomes a challenging task, especially when using non‐Newtonian fluids. In this study, computational fluid dynamics (CFD) has been applied to simulate the solid‐liquid mixing of silica particles with non‐Newtonian fluids of carboxymethyl cellulose (CMC) solutions (1.0, 1.5, and 2.0). The model is validated by experimental measurement of power consumption and solid‐phase concentration. The scale‐up criterion based on geometric similarity and constant tip speed is proved to be valid for non‐Newtonian systems by comparing kinematic similarity. The transformation of flow regime is discussed based on modified Reynolds number and local Reynolds number. The scale‐up criterion performs well in terms of the scale effect of power consumption, especially for the CMC2.0 solution system. This study is instructive for the scale‐up of non‐Newtonian fluid mixing in stirred tanks.
Empirical analysis of debt maturity, cash holdings and firm investment in developing economies
Authors: Nnadi Matthias , Surichamorn Vachiraporn , Jayasekera Ranadeva , Belghitar Yacine
Published: January 2021

This study investigates the potential simultaneous relationships among leverage, debt maturity and cash holdings and how these jointly affect financial policy and firms' investment activities in developing countries of Thailand, Indonesia and Singapore during the period 2006–2015. Using the two‐step system GMM estimator, our results show that high‐growth firms not only shorten debt maturity to reduce the underinvestment incentive, but also decrease leverage to reduce liquidity risk. We find evidence that the level of cash holdings is a key determinant of leverage in all countries and that debt policy and growth opportunities affect the investment decision of firms in Thailand and Singapore whereas cash policy is more important in Indonesia. These findings have significant implications for investment decisions in these economies.
Effects of neonatal lung abnormalities on parenchymal R2* estimates
Authors: Hahn Andrew D. , Malkus Annelise , Kammerman Jeffery , Higano Nara , Walkup Laura L. , Woods Jason , Fain Sean B.
Published: January 2021

Infants admitted to the neonatal intensive care unit (NICU) often suffer from multifaceted pulmonary morbidities that are not well understood. Ultrashort echo time (UTE) magnetic resonance imaging (MRI) is a promising technique for pulmonary imaging in this population without requiring exposure to ionizing radiation. The aims of this study were to investigate the effect of neonatal pulmonary disease on R2* and tissue density and to utilize numerical simulations to evaluate the effect of different alveolar structures on predicted R2*.This was a prospective study, in which 17 neonatal human subjects (five control, seven with bronchopulmonary dysplasia [BPD], five with congenital diaphragmatic hernia [CDH]) were enrolled. Twelve subjects were male and five were female, with postmenstrual age (PMA) at MRI of 39.7 ± 4.7 weeks. A 1.5T/multiecho three‐dimensional UTE MRI was used. Pulmonary R2* and tissue density were compared across disease groups over the whole lung and regionally. A spherical shell alveolar model was used to predict the expected R2* over a range of tissue densities and tissue susceptibilities. Tests for significantly different mean R2* and tissue densities across disease groups were evaluated using analysis of variance, with subsequent pairwise group comparisons performed using t tests. Lung tissue density was lower in the ipsilateral lung in CDH compared to both controls and BPD patients (both p < 0.05), while only the contralateral lung in CDH (CDHc) had higher whole‐lung R2* than both controls and BPD (both p < 0.05). R2* differences were significant between controls and CDHc within all tissue density ranges (all p < 0.05) with the exception of the 80%–90% range (p = 0.17). Simulations predicted an inverse relationship between alveolar tissue density and R2* that matches empirical human data. Alveolar wall thickness had no effect on R2* independent of density (p = 1). The inverse relationship between R2* and tissue density is influenced by the presence of disease globally and regionally in neonates with BPD and CDH in the NICU.

Level of Evidence

2.

Technical Efficacy Stage

2.
Comparison of the effectiveness of variable selection method for creating a diagnostic panel of biomarkers for mass spectrometric lipidome analysis
Authors: Tokareva Alisa O. , Chagovets Vitaliy V. , Kononikhin Alexey S. , Starodubtseva Natalia L. , Nikolaev Evgeny N. , Frankevich Vladimir E.
Published: January 2021

Hundreds of compounds are detected during untargeted lipidomics analysis. The potential efficacy of lipids as disease markers makes it important to select the species with the most discriminative potential. Datasets based on a selected class of lipids allow the development of a high‐quality diagnostic model using orthogonal projection on latent structure. The combination of selection of lipids by variable importance in projection and by Akaike information criteria makes it possible to build a reliable diagnostic model based on logistic regression.
Compatibilizing effect and reinforcing efficiency of nanosilica on ethylene‐propylene diene monomer/chloroprene rubber blends
Authors: Eslami Zahra , Mirzapour Miraidin
Published: January 2021

This study shows an approach of compatibilization between ethylene‐propylene diene monomer (EPDM) and Chloroprene Rubber (CR) by using nanosilica (SiO2) as a compatibilizer and, at the same time, as a strong reinforcing nanofiller. The effect of nanosilica and rubber composition was studied on microstructure and mechanical properties of the cured EPDM/CR/SiO2. The microstructure of compounds were characterized using scanning electron microscopy and transmission electron microscopy, which demonstrated that the observed nanoSiO2 were in both EPDM and CR phases. It was found that the addition of nanosilica had massive improvement on modulus, tensile strength, and dynamic mechanical thermal analysis of the samples. With the incorporation of just 10 phr nano‐SiO2, the storage modulus above the glass transition region of CR50 increased from about 3.9 to 7.16 MPa. Moreover, the investigation of glass transition temperature (Tg) values showed that the compatibility of EPDM and CR in the compound enhanced with the addition of nanosilica, which in turn contributes to improving the properties of compounds. In addition, the results of mechanical properties of the samples revealed that the tensile strength, elongation at break and modulus of CR50 after modifying with 10 phr of nanosilica increased by around 398%, 33%, and 135%, respectively.
Correction to: A Range of Earth Observation Techniques for Assessing Plant Diversity
Authors: Lausch Angela , Heurich Marco , Magdon Paul , Rocchini Duccio , Schulz Karsten , Bumberger Jan , King Doug J.
Published: January 2021

The original version of this book was inadvertently published with an incorrect affiliation.
Using the GDELT Dataset to Analyse the Italian Sovereign Bond Market
Authors: Consoli Sergio , Pezzoli Luca Tiozzo , Tosetti Elisa
Published: January 2021

The Global Data on Events, Location, and Tone (GDELT) is a real time large scale database of global human society for open research which monitors worlds broadcast, print, and web news, creating a free open platform for computing on the entire world’s media. In this work, we first describe a data crawler, which collects metadata of the GDELT database in real-time and stores them in a big data management system based on Elasticsearch, a popular and efficient search engine relying on the Lucene library. Then, by exploiting and engineering the detailed information of each news encoded in GDELT, we build indicators capturing investor’s emotions which are useful to analyse the sovereign bond market in Italy. By using regression analysis and by exploiting the power of Gradient Boosting models from machine learning, we find that the features extracted from GDELT improve the forecast of country government yield spread, relative that of a baseline regression where only conventional regressors are included. The improvement in the fitting is particularly relevant during the period government crisis in May-December 2018.
Care Work and Parenting
Authors: Suwada Katarzyna
Published: January 2021

This chapter deals with the organisation of care work by Polish parents. Using the data from in-depth interviews and survey data, I demonstrate cultural norms about care that prevails in Polish society. Strong gendered norms and instruments of family policy shape different opportunity structures for men and women. I focus on how parental leaves are used and perceived by Polish parents. I argue that they are still seen primarily as women’s right. I analyse the reasoning lying behind such thinking, but also show the experiences of parents who decided to share the leave. Then I proceed to the organisation of care in the context of so-called care gap. The Polish system of parental leaves is incompatible with the system of institutional care for children. Consequently, in the period between the end of paid leave and the time when a child can go to a kindergarten parents have to develop different strategies how to provide care for their children. I show how these strategies differ in the context of economic inequalities, as well as what consequences care gap has on gender inequalities. Finally, the chapter finishes with the analysis of how care work is perceived by parents.
Domestic Work and Parenting
Authors: Suwada Katarzyna
Published: January 2021

This chapter deals with the last type of work distinguished in the beginning of the book—domestic work. Domestic work is often perceived as the most undesirable type of work. I describe here different attitudes of men and women to domestic work. My analysis shows great gender inequalities. Men are still perceived as helpers of women, whereas women are overwhelmed with the obligation to manage everyday life of their families. I distinguish different strategies used by men to avoid domestic duties, as well as women’s attitudes to them. The chapter deals also with the concept of fairness. I show how parents define fairness and I argue that fairness does not have to mean equality in the division of domestic work. The chapter finishes with the strategies of reducing the number of hours devoted to domestic duties. It shows how that economic inequalities cannot be ignored when discussing this issue, as well as various situations of single and coupled parents.
Conclusions: Parenting in Times of Prevailing Inequalities
Authors: Suwada Katarzyna
Published: January 2021

The final chapter of the book briefly summarises the key points of the previous chapters and addresses the central conclusions of the book. I underline how analysing parenting from the perspective of three types of work (paid work, care work and domestic work) help to recognise prevailing gender and economic inequalities in Polish society. I also argue that the opportunity structures of mothers and fathers greatly differ, and that it has its sources in the family policy system.
Erratum to: Matching scalar leptoquarks to the SMEFT at one loop
Authors: Gherardi Valerio , Marzocca David , Venturini Elena
Published: January 2021

The correct equations have been substituted in the e-print version of ref [1]. We thank Konstantinos Mantzaropoulos for pointing out these corrections to us, after a comparison with results obtained via functional methods.
New $$ \mathcal{N} $$ = 2 superconformal field theories from $$ \mathcal{S} $$-folds
Authors: Giacomelli Simone , Meneghelli Carlo , Peelaers Wolfger
Published: January 2021

Abstract

We study the four-dimensional $$ \mathcal{N} $$
N
= 2 superconformal field theories that describe D3-branes probing the recently constructed $$ \mathcal{N} $$
N
= 2 $$ \mathcal{S} $$
S
-folds in F-theory. We introduce a novel, infinite class of superconformal field theories related to $$ \mathcal{S} $$
S
-fold theories via partial Higgsing. We determine several properties of both the $$ \mathcal{S} $$
S
-fold models and this new class of theories, including their central charges, Coulomb branch spectrum, and moduli spaces of vacua, by bringing to bear an array of field-theoretical techniques, to wit, torus-compactifications of six-dimensional $$ \mathcal{N} $$
N
= (1, 0) theories, class $$ \mathcal{S} $$
S
technology, and the SCFT/VOA correspondence.
A 4d $$ \mathcal{N} $$ = 1 Cardy Formula
Authors: Kim Joonho , Kim Seok , Song Jaewon
Published: January 2021

Abstract

We study the asymptotic behavior of the (modified) superconformal index for 4d $$ \mathcal{N} $$
N
= 1 gauge theory. By considering complexified chemical potential, we find that the ‘high-temperature limit’ of the index can be written in terms of the conformal anomalies 3c − 2a. We also find macroscopic entropy from our asymptotic free energy when the Hofman-Maldacena bound 1/2 < a/c < 3/2 for the interacting SCFT is satisfied. We study $$ \mathcal{N} $$
N
= 1 theories that are dual to AdS5 × Yp,p and find that the Cardy limit of our index accounts for the Bekenstein-Hawking entropy of large black holes.
Derived categories of quintic del Pezzo fibrations
Authors: Xie Fei
Published: January 2021

We provide a semiorthogonal decomposition for the derived category of fibrations of quintic del Pezzo surfaces with rational Gorenstein singularities. There are three components, two of which are equivalent to the derived categories of the base and the remaining non-trivial component is equivalent to the derived category of a flat and finite of degree 5 scheme over the base. We introduce two methods for the construction of the decomposition. One is the moduli space approach following the work of Kuznetsov on the sextic del Pezzo fibrations and the components are given by the derived categories of fine relative moduli spaces. The other approach is that one can realize the fibration as a linear section of a Grassmannian bundle and apply homological projective duality.
Rapid movements in plants
Authors: Mano Hiroaki , Hasebe Mitsuyasu
Published: January 2021

Plant movements are generally slow, but some plant species have evolved the ability to move very rapidly at speeds comparable to those of animals. Whereas movement in animals relies on the contraction machinery of muscles, many plant movements use turgor pressure as the primary driving force together with secondarily generated elastic forces. The movement of stomata is the best-characterized model system for studying turgor-driven movement, and many gene products responsible for this movement, especially those related to ion transport, have been identified. Similar gene products were recently shown to function in the daily sleep movements of pulvini, the motor organs for macroscopic leaf movements. However, it is difficult to explain the mechanisms behind rapid multicellular movements as a simple extension of the mechanisms used for unicellular or slow movements. For example, water transport through plant tissues imposes a limit on the speed of plant movements, which becomes more severe as the size of the moving part increases. Rapidly moving traps in carnivorous plants overcome this limitation with the aid of the mechanical behaviors of their three-dimensional structures. In addition to a mechanism for rapid deformation, rapid multicellular movements also require a molecular system for rapid cell-cell communication, along with a mechanosensing system that initiates the response. Electrical activities similar to animal action potentials are found in many plant species, representing promising candidates for the rapid cell–cell signaling behind rapid movements, but the molecular entities of these electrical signals remain obscure. Here we review the current understanding of rapid plant movements with the aim of encouraging further biological studies into this fascinating, challenging topic.
Zero Watermarking: Critical Analysis of Its Role in Current Medical Imaging
Authors: Roček Aleš , Javorník Michal , Slavíček Karel , Dostál Otto
Published: January 2021

Medical image data plays a critical role in health care today. Whatever the context of image processing (research and educational activities, diagnostic or forensic purposes, etc.), they are supposed to be treated as highly sensitive. Unfortunately, currently available image-processing tools also enable very sophisticated malicious modification of their content.

This paper is focused on the assessment of the effectiveness of selected so-called zero watermarking methods (ones that do not cause any modification of an image sample), in the protection of the integrity, and proving authorship, of these medical image studies. We have studied many zero watermarking methods and selected one representative from each type of known algorithms for comparison.

We have conducted a series of simulations over a huge research database of anonymized medical image studies (patient examinations).
Influence of MOOC learners discussion forum social interactions on online reviews of MOOC
Authors: Wu Bing
Published: January 2021

Although some studies have explored massive open online courses (MOOCs) discussion forums and MOOC online reviews separately, studies of both aspects are insufficient. Based on the theory of self-determination, this paper proposes research hypotheses that MOOC learning progress has a direct impact on MOOC online reviews and an indirect influence on MOOC online reviews through social interactions in discussion forums, as well. Coursera the largest MOOC platform, is selected as the empirical research object, and data from learners who participated in the MOOC discussion forum and provided MOOC online reviews from August 2016 to December 2019 are obtained from the most popular course, “Machine Learning”. After processing, data from 4376 learners are obtained. Then, according to research hypotheses, multi regression models are constructed accordingly. The results show that the length of MOOC online review text is affected by the MOOC learning progress, the number of discussion forum posts, the number of follow, the online review sentiment and MOOC rating. This study highlights the main factors that affect MOOC online reviews. As a result, some suggestions are put forward for the construction of MOOC.