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1.
Am J Cardiol ; 133: 162-165, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33172590

RESUMO

Adolf Fick was a German physiologist, born in Kassel in 1829, who studied medicine at the University of Marburg and graduated in 1851. He worked first in Zurich and then in Wurzburg. Most of his studies were based on physics and mathematics, and deep analysis, and only later were proven by experiments. Fick's name in physics is associated to the laws of diffusion of solutions, and in medicine to the principle of cardiac output calculation. In 1855, he proposed Fick's laws on gas diffusion. In 1870, he devised Fick's principle, which allows the measurement of cardiac output and calculations of intracardiac shunts from the arteriovenous oxygen difference. The method was later generalized to the Fick principle, according to which the flow of an indicator taken up or released by an organ corresponds to the difference between the indicator flows in the inflow and outflow tracts. Fick invented several devices most of them aimed to improve precision in his physiologic experiments. In 1868, he invented the plethysmograph, for recording the speed of blood in the human artery. In 1888, the tonometer for measuring from outside the hydrostatic pressure inside the eyeball. After 3 decades as Professor in Wurzburg, he retired. Fick died at Blankenberge, Belgium in 1901 age 71 years old.


Assuntos
Débito Cardíaco , Cardiologia/história , Doenças Cardiovasculares/história , Fisiologia/história , Doenças Cardiovasculares/fisiopatologia , Alemanha , História do Século XIX , História do Século XX , Humanos , Matemática/história
2.
PLoS One ; 15(10): e0239224, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33006984

RESUMO

Individuals with Mathematics Learning Disabilities have persistent mathematics underperformance but vary with respect to their cognitive profiles. The present study examined mathematics ability and achievement, and associated mathematics-specific numerical skills and domain-general cognitive abilities, in young children with Turner syndrome compared to their matched peers. We utilized two independent peer groups so that group comparisons would account for verbal skills, a hypothesized strength of girls with Turner syndrome, and nonsymbolic magnitude comparison skills, a hypothesized difference of girls with Turner syndrome. This individual matching approach afforded characterization of mathematics profiles of girls with Turner syndrome and girls without Turner syndrome that share potential key features of the Turner syndrome phenotype. Results indicated differences in mathematics ability and nonsymbolic magnitude comparison tasks between girls with Turner syndrome and peers with similar levels of verbal skill. Mathematics ability and mathematics achievement scores of girls with Turner syndrome did not differ significantly from their peers with similar levels of accuracy on a nonsymbolic magnitude comparison task. Cognitive correlates of mathematics outcomes showed disparate patterns across groups. These quantitative and qualitative differences across profiles enhance our understanding of variation in mathematics ability in early childhood and inform how mathematics skills develop in young children with or without Turner syndrome.


Assuntos
Logro , Cognição , Matemática , Síndrome de Turner/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino
3.
Nat Commun ; 11(1): 5021, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024117

RESUMO

Engineered biocircuits designed with biological components have the capacity to expand and augment living functions. Here we demonstrate that proteases can be integrated into digital or analog biocircuits to process biological information. We first construct peptide-caged liposomes that treat protease activity as two-valued (i.e., signal is 0 or 1) operations to construct the biological equivalent of Boolean logic gates, comparators and analog-to-digital converters. We use these modules to assemble a cell-free biocircuit that can combine with bacteria-containing blood, quantify bacteria burden, and then calculate and unlock a selective drug dose. By contrast, we treat protease activity as multi-valued (i.e., signal is between 0 and 1) by controlling the degree to which a pool of enzymes is shared between two target substrates. We perform operations on these analog values by manipulating substrate concentrations and combine these operations to solve the mathematical problem Learning Parity with Noise (LPN). These results show that protease activity can be used to process biological information by binary Boolean logic, or as multi-valued analog signals under conditions where substrate resources are shared.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Peptídeo Hidrolases/metabolismo , Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Peptídeos Catiônicos Antimicrobianos/farmacologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Eritrócitos/microbiologia , Escherichia coli , Proteínas de Escherichia coli/metabolismo , Hemólise , Humanos , Lipossomos , Matemática , Pró-Fármacos , Biologia Sintética/métodos
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2999-3002, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018636

RESUMO

Mental stress is a prevalent issue in the modern society and a prominent contributing factor to various physical and psychological diseases. This paper investigates the feasibility of detecting different stress levels using electroencephalography (EEG), and evaluates the effectiveness of various stress-relief methods. EEG data were collected from 25 subjects while they were at rest and under 3 different levels of stress induced by mental arithmetic tasks. Nine features that correlate with stress from existing literature were extracted. Subsequently, discriminative features were selected by Fisher Ratio and used to train a Linear Discriminant Analysis classifier. Results from 10-fold cross-validation yielded averaged intra-subject classification accuracy of 85.6% for stress versus rest, 7l.2% for two levels of stress and rest, and 58.4% for three levels of stress and rest. The results showed high promise of using EEG to detect level of stress, and the features selected showed that Beta brain waves (13-30HZ) and prefrontal relative Gamma power are most discriminative. Five different stress-relief methods were then evaluated, and the method of hugging a pillow was found to be the most effective measure relatively in decreasing the stress level detected using EEG. These results show promise of future research in real-time stress detection and reduction using EEG for stress management and relief.


Assuntos
Ondas Encefálicas , Eletroencefalografia , Análise Discriminante , Humanos , Matemática , Estresse Psicológico/diagnóstico
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 6013-6017, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019342

RESUMO

To bridge the gap between the biological sciences (typically female-dominated) and engineering (typically male-dominated), biomedical engineering (BME) activities could potentially be used as a vehicle to alter female students' perception of engineering as a whole. Female's pursuit of STEM (Science, Technology, Engineering and Math) degrees is typically confined to the biological sciences and females earn a high proportion of degrees in nursing, psychology and the social sciences, yet male presence persists in physical sciences and engineering. Female's participation in engineering remains much lower than men at all degree levels. Here, research questions included do female high school students: 1) perceive engineering as relevant? 2) have an interest & aptitude towards exploring engineering in college and as a career? 3) have anxiety in terms of engineering? 4) have engineering "role-confidence"? Participants, a randomly selected pool of 28 high school students (almost exclusively female from schools throughout the DC Metro area) took part in a week-long, all-day workshop where they were exposed to female engineering mentors, peers, and activities tied to BME & Engineering. Pre and post surveys, adapted from standard STEM surveys, were administered to the pool of participants. Increases in confidence and interest in engineering and decreased anxiety were observed following female high school students' participation in hands-on activities in BME.


Assuntos
Engenharia Biomédica , Engenharia , Engenharia Biomédica/educação , Feminino , Humanos , Masculino , Matemática , Tecnologia , Universidades
6.
Zootaxa ; 4816(3): zootaxa.4816.3.12, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-33055700

RESUMO

Geometric morphometrics (GM) is a powerful analytical approach for evaluating phenotypic variation relevant to taxonomy and systematics, and as with any statistical methodology, requires adherence to fundamental assumptions for inferences to be strictly valid. An important consideration for GM is how landmark configurations, which represent sets of anatomical loci for evaluating shape variation through Cartesian coordinates, relate to underlying homology (Zelditch et al. 1995; Polly 2008). Perhaps more so than with traditional morphometrics, anatomical homology is a crucial assumption for GM because of the mathematical and biological interpretations associated with shape change depicted by deformation grids, such as the thin plate spline (Klingenberg 2008; Zelditch et al. 2012). GM approaches are often used to analyze shapes or outlines of structures, which are not necessarily related to common ancestry, and in this respect GM approaches that use linear semi-landmarks and related methods are particularly amenable to evaluating primary homology, or raw similarity between structures (De Pinna 1991; Palci Lee 2019). This relaxed interpretation of homology that focuses more on recognizable and repeatable landmarks is defensible so long as authors are clear regarding the purpose of the analyses and in defining their landmark configurations (Palci Lee 2019). Secondary homology, or similarity due to common ancestry, can also be represented with GM methods and is often assumed to be reflected in fixed Type 1 (juxtaposition of tissues) or Type 2 (self-evident geometry) landmarks (Bookstein 1991).


Assuntos
Biometria , Répteis , Animais , Matemática
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3634-3637, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018789

RESUMO

Deep brain stimulation (DBS) involves activation of targeted brain tissue through implantable electrodes to treat neurological disorders. In this study, two novel electrode designs, recessed flat-contact and recessed curvature-contact models were developed where the electrode contacts were recessed to a specified depth to improve directional selectivity. Furthermore, the contact geometry was also modified for the recessed curvature-contact model in order to obtain a hemispherical configuration that will help increase current steering and reduce the propensity of tissue damage. The predicted tissue damage produced by these models were compared to the standard array model using the Shannon tissue damage model criteria. Furthermore, the volume of tissue activated by each of the electrode models was analyzed, and the radial projection relative to the total projection of each geometry was determined as a measure of directional selectivity. Based on the trends observed in the current density, tissue damage, and volume of tissue activated (VTA) analyses, it is inferred that the recessed contact electrode geometries help improve directional selectivity and safety of DBS.


Assuntos
Estimulação Encefálica Profunda , Encéfalo , Eletrodos Implantados , Matemática , Modelos Neurológicos
8.
CBE Life Sci Educ ; 19(3): es8, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32870083

RESUMO

Cognitive neuroscience research is typically conducted in controlled laboratory environments that hold very little resemblance to science, technology, engineering, and mathematics classrooms. Fortunately, recent advances in portable electroencephalography technology now allow researchers to collect brain data from groups of students in real-world classrooms. Even though this line of research is still new, there is growing evidence that students' engagement, memory retention, and social dynamics are reflected in the brain-to-brain synchrony between students and teachers (i.e., the similarity in their brain responses). In this Essay, I will provide an overview of this emerging line of research, discuss how this approach can facilitate new collaborations between neuroscientists and discipline-based education researchers, and propose directions for future research.


Assuntos
Encéfalo/fisiologia , Engenharia/educação , Matemática/educação , Ciência/educação , Tecnologia/educação , Universidades , Humanos , Relações Interpessoais , Estudantes/psicologia
9.
Nature ; 585(7825): 357-362, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939066

RESUMO

Array programming provides a powerful, compact and expressive syntax for accessing, manipulating and operating on data in vectors, matrices and higher-dimensional arrays. NumPy is the primary array programming library for the Python language. It has an essential role in research analysis pipelines in fields as diverse as physics, chemistry, astronomy, geoscience, biology, psychology, materials science, engineering, finance and economics. For example, in astronomy, NumPy was an important part of the software stack used in the discovery of gravitational waves1 and in the first imaging of a black hole2. Here we review how a few fundamental array concepts lead to a simple and powerful programming paradigm for organizing, exploring and analysing scientific data. NumPy is the foundation upon which the scientific Python ecosystem is constructed. It is so pervasive that several projects, targeting audiences with specialized needs, have developed their own NumPy-like interfaces and array objects. Owing to its central position in the ecosystem, NumPy increasingly acts as an interoperability layer between such array computation libraries and, together with its application programming interface (API), provides a flexible framework to support the next decade of scientific and industrial analysis.


Assuntos
Biologia Computacional/métodos , Matemática , Linguagens de Programação , Design de Software
10.
An. psicol ; 36(2): 262-270, mayo 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-192063

RESUMO

Many previous studies have discussed the influence of extrinsic factors (e.g. living environment) on academic achievement of children from western China. The present study focused on four non-cognitive factors, self-educational aspiration, self-efficacy, instrumental motivation, and anxiety, which could affect mathematics achievement. The purpose of this study was to investigate the mechanisms how these four non-cognitive factors affected mathematics achievement. 5774 primary school students from 4th and 5th grade in western China participated in this study. A moderated chained mediation model was constructed. The results showed that self-educational aspiration could positively predict mathematics achievement. However, instrumental motivation and anxiety formed chained mediation between self-educational aspiration and mathematics achievement, and negatively predicted mathematics achievement. Besides, self-efficacy played a moderated role in the relationship between self-educational aspiration and anxiety


Muchos estudios previos han discutido la influencia de factores extrínsecos (por ejemplo, entorno vital) en el logro académico de los niños de China occidental. El presente estudio se centró en cuatro factores no cognitivos, la aspiración autoeducativa, la autoeficacia, la motivación instrumental y la ansiedad, los cuales podrían afectar el logro matemático. El propósito de este estudio fue investigar los mecanismos por los cuales estos cuatro factores no cognitivos afectaron el logro matemático. Un total de 5774 estudiantes de primaria de 4º y 5º grado en el oeste de China participaron en este estudio. Se construyó un modelo de mediación encadenado moderado. Los resultados mostraron que la aspiración autoeducativa podría predecir positivamente el logro matemático. Sin embargo, la motivación instrumental y la ansiedad formaron una mediación encadenada entre la aspiración autoeducativa y el logro matemático, y predijeron negativamente el logro matemático. Además, la autoeficacia desempeñó un papel moderado en la relación entre la aspiración autoeducativa y la ansiedad


Assuntos
Humanos , Masculino , Feminino , Criança , Autoeficácia , Modelos Psicológicos , Matemática/educação , Estudantes/psicologia , Aspirações Psicológicas , Ansiedade/psicologia , Estudantes/estatística & dados numéricos , Motivação , Inquéritos e Questionários , Sucesso Acadêmico
11.
PLoS One ; 15(9): e0238230, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32898854

RESUMO

In a cross-sectional study of youth ages 8-15, we examined implicit and explicit gender stereotypes regarding math and language abilities. We investigated how implicit and explicit stereotypes differ across age and gender groups and whether they are consistent with cultural stereotypes. Participants (N = 270) completed the Affect Misattribution Procedure (AMP) and a survey of explicit beliefs. Across all ages, boys showed neither math nor language implicit gender biases, whereas girls implicitly favored girls in both domains. These findings are counter to cultural stereotypes, which favor boys in math. On the explicit measure, both boys' and girls' primary tendency was to favor girls in math and language ability, with the exception of elementary school boys, who rated genders equally. We conclude that objective gender differences in academic success guide differences in children's explicit reports and implicit biases.


Assuntos
Idioma , Matemática/educação , Autoimagem , Sexismo/estatística & dados numéricos , Estudantes/psicologia , Adolescente , Fatores Etários , Aptidão , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Fatores Sexuais , Estereotipagem
12.
PLoS One ; 15(9): e0238250, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32936827

RESUMO

The present study tests predictions from the Tripartite Integration Model of Social Influences (TIMSI) concerning processes linking social interactions to social integration into science, technology, engineering, and mathematics (STEM) communities and careers. Students from historically overrepresented groups in STEM were followed from their senior year of high school through their senior year in college. Based on TIMSI, we hypothesized that interactions with social influence agents (operationalized as mentor network diversity, faculty mentor support, and research experiences) would promote both short- and long-term integration into STEM via social influence processes (operationalized as science self-efficacy, identity, and internalized community values). Moreover, we examined the previously untested hypothesis of reciprocal influences from early levels of social integration in STEM to future engagement with social influence agents. Results of a series of longitudinal structural equation model-based mediation analyses indicate that, in the short term, higher levels of faculty mentorship support and research engagement, and to a lesser degree more diverse mentor networks in college promote deeper integration into the STEM community through the development of science identity and science community values. Moreover, results indicate that, in the long term, earlier high levels of integration in STEM indirectly influences research engagement through the development of higher science identity. These results extend our understanding of the TIMSI framework and advance our understanding of the reciprocal nature of social influences that draw students into STEM careers.


Assuntos
Engenharia/educação , Matemática/educação , Modelos Estatísticos , Ciência/educação , Apoio Social , Estudantes/psicologia , Tecnologia/educação , Adulto , Escolha da Profissão , Feminino , Humanos , Estudos Longitudinais , Masculino , Mentores , Modelos Psicológicos , Motivação , Autoeficácia , Inquéritos e Questionários , Universidades , Adulto Jovem
15.
J Vis Exp ; (161)2020 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-32744523

RESUMO

The purpose of this study was to describe a Spanish protocol that includes reading, writing, and math Curriculum-Based Measures (CBMs) aimed at early detection of students at risk of presenting learning disabilities (LD). Early identification of LD is a critical component of the Response to Intervention (RtI) model. In early grades, the screening of foundational skills mentioned above can provide a data-based guideline for identifying students requiring a more intensive response-based intervention before starting elementary school. We designed different CBMs based on indicators of basic early reading, writing, and math skills [Indicadores de Progreso de Aprendizaje en Lectura, Escritura y Matemáticas, IPAL, IPAE, and IPAM respectively] that aim to fulfill the twofold objective of universal screening and evaluation of the Spanish students' progress. For reading, IPAL includes alphabetic principle, phonological awareness, concepts about print, and riddles in kindergarten. In first and second grades, IPAL includes alphabetic principle, nonsense words fluency, maze sentences, and oral reading fluency. In addition, it includes phonemic segmentation for first grade and prosody for second grade. For writing, IPAE includes copying letters, writing allographs, dictated letters, dictated words with arbitrary spelling, dictated words with rule-based spelling, dictated nonsense words, dictated sentences, writing sentences, and writing a story for first-third grades. Finally, for math, IPAM includes number comparison, missing number, number identification, quantity array, and counting aloud for kindergarten, and number comparison, multi-digit computation, missing number, single-digit computation, and place value for first-third grades.


Assuntos
Deficiências da Aprendizagem , Matemática , Leitura , Ensino , Redação , Criança , Feminino , Humanos , Idioma , Masculino , Estudantes
16.
Artigo em Inglês | MEDLINE | ID: mdl-32630336

RESUMO

This study aimed to investigate secondary students' mathematics achievement emotions and their mediating effects on the relationships between classroom environmental characteristics, namely, teacher-student interactional styles (i.e., teacher leadership and student freedom styles), and students' mathematics learning outcomes in mainland China. A sample of 1423 Grade 7 to 9 junior secondary students responded to a questionnaire that comprised three sets of scales for assessing students' perceived teacher-student interactional styles, mathematics achievement emotions, and cognitive and affective learning outcomes. The results indicated that students' mathematics learning outcomes were positively associated with both teacher leadership and student freedom styles. Moreover, students' mathematics achievement emotions mediated the relationships between these two interactional styles and their mathematics learning outcomes. These results highlight the importance of mathematics achievement emotions in student learning, and provide implications for the improvement of mathematics classroom environments.


Assuntos
Logro , Matemática/educação , Estudantes , Adolescente , Criança , China , Emoções , Humanos
17.
PLoS One ; 15(7): e0235383, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645110

RESUMO

A major concern among universities around the world is that female students face gender bias, discrimination and related barriers in male-dominated STEM fields. To investigate this concern, we conducted a novel large-scale experiment of interactions between female and male students in one of the most important gateway courses for the Sciences and a course in which students interact one-on-one extensively throughout the term. Over the past four years, at a large public research university, we randomly paired every student enrolled in an introductory Chemistry lab (3,902 students and total N = 5,537). Using precise estimates from the experiment, we provide novel evidence that female students are not negatively affected academically by male partners. When assigned a male partner, female students do not receive lower scores or grades, and they are no more likely to drop the course or not continue in Chemistry or a STEM field. We also find that academically weaker female students are not negatively affected by male students and that female students are not negatively affected when paired with academically stronger male students. Although previous studies have documented that female students self-report experiencing gender bias from male peers in STEM, importantly, we do not find evidence that female students are negatively affected by male peers in intensive, long-term pairwise interactions in their course grades or future STEM course taking. The findings provide hopeful news for future trends in female representation in STEM fields.


Assuntos
Currículo , Engenharia/educação , Matemática/educação , Grupo Associado , Ciência/educação , Estudantes , Tecnologia/educação , Universidades , Feminino , Humanos , Masculino , Distribuição Aleatória , Análise de Regressão , Ensino
18.
Igaku Butsuri ; 40(2): 55-60, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32611943

RESUMO

This manuscript is a supplement to the machine learning course at JSMP Medical Physics Summer School held in 2019. The idea of Kulbuck-Leibler divergence, a key concept in machine learning, is introduced with mutual information.


Assuntos
Aprendizado de Máquina , Matemática
19.
PLoS One ; 15(7): e0236153, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726352

RESUMO

Mathematics is often promoted as endowing those who study it with transferable skills such as an ability to think logically and critically or to have improved investigative skills, resourcefulness and creativity in problem solving. However, there is scant evidence to back up such claims. This project tested participants with increasing levels of mathematics training on 11 well-studied rational and logical reasoning tasks aggregated from various psychological studies. These tasks, that included the Cognitive Reflection Test and the Wason Selection Task, are of particular interest as they have typically and reliably eluded participants in all studies, and results have been uncorrelated with general intelligence, education levels and other demographic information. The results in this study revealed that in general the greater the mathematics training of the participant, the more tasks were completed correctly, and that performance on some tasks was also associated with performance on others not traditionally associated. A ceiling effect also emerged. The work is deconstructed from the viewpoint of adding to the platform from which to approach the greater, and more scientifically elusive, question: are any skills associated with mathematics training innate or do they arise from skills transfer?


Assuntos
Criatividade , Inteligência , Lógica , Matemática/educação , Resolução de Problemas/fisiologia , Estudantes/psicologia , Pensamento/fisiologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Adulto Jovem
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