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2.
Psychol Sci ; 30(3): 396-404, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30653407

RESUMEN

How often are creative ideas generated during episodes of mind wandering, and do they differ from those generated while on task? In two studies ( N = 98, N = 87), professional writers and physicists reported on their most creative idea of the day, what they were thinking about and doing when it occurred, whether the idea felt like an "aha" moment, and the quality of the idea. Participants reported that one fifth of their most significant ideas of the day were formed during spontaneous task-independent mind wandering-operationalized here as (a) engaging in an activity other than working and (b) thinking about something unrelated to the generated idea. There were no differences between ratings of the creativity or importance of ideas that occurred during mind wandering and those that occurred on task. However, ideas that occurred during mind wandering were more likely to be associated with overcoming an impasse on a problem and to be experienced as "aha" moments, compared with ideas generated while on task.


Asunto(s)
Creatividad , Física/estadística & datos numéricos , Conducta Errante/psicología , Adulto , Femenino , Humanos , Masculino , Pensamiento/fisiología , Escritura
8.
Am J Pharm Educ ; 84(8): ajpe7610, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32934382

RESUMEN

Objective. To assess the degree of change in the level of scientific reasoning in first-year pharmacy students by applying active-learning methods during a physics course. Methods. The efficiency of the active-learning methods of experimentation and discussion in the development of scientific reasoning in 90 pharmacy students was determined by comparing it to the efficiency of using traditional learning methods (eg, lecture) with 60 students. The Lawson Classroom Test of Scientific Reasoning was used to measure change. Results. The data from this five-year study showed that of all pharmacy students in the active-learning group who were functioning on a stable or transitional level of thinking at the time of the pretest, 28.6% achieved a shift towards a higher level of scientific thinking. The active-learning group also achieved better overall results in the course. Conclusion. Using active-learning methods (experimentation and discussion) in a physics course enabled pharmacy students to better master the content. By elevating students' level of scientific reasoning, a foundation for using evidence-based medicine was established.


Asunto(s)
Educación en Farmacia/métodos , Educación en Farmacia/estadística & datos numéricos , Evaluación Educacional/estadística & datos numéricos , Física/estadística & datos numéricos , Aprendizaje Basado en Problemas/estadística & datos numéricos , Estudiantes de Farmacia/estadística & datos numéricos , Adulto , Curriculum/estadística & datos numéricos , Humanos , Solución de Problemas , Encuestas y Cuestionarios , Adulto Joven
9.
PLoS One ; 15(12): e0243913, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33332441

RESUMEN

We analyse academic success using a genealogical approach to the careers of over 95,000 scientists in mathematics and associated fields in physics and chemistry. We look at the effect of Ph.D. supervisors (one's mentors) on the number of Ph.D. students that one supervises later on (one's mentees) as a measure of academic success. Supervisors generally provide important inputs in Ph.D. projects, which can have long-lasting effects on academic careers. Moreover, having multiple supervisors exposes one to a diversity of inputs. We show that Ph.D. students benefit from having multiple supervisors instead of a single one. The cognitive diversity of mentors has a subtler effect in that it increases both the likelihood of success (having many mentees later on) and failure (having no mentees at all later on). We understand the effect of diverse mentorship as a high-risk, high-gain strategy: the recombination of unrelated expertise often fails, but sometimes leads to true novelty.


Asunto(s)
Éxito Académico , Selección de Profesión , Matemática/estadística & datos numéricos , Ciencia/estadística & datos numéricos , Química/estadística & datos numéricos , Femenino , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Masculino , Matemática/historia , Mentores/historia , Física/historia , Física/estadística & datos numéricos , Investigadores/historia , Investigadores/psicología , Estudiantes/historia , Estudiantes/estadística & datos numéricos
10.
Medicine (Baltimore) ; 99(40): e22623, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33019485

RESUMEN

PURPOSE: To identify the 100 most cited research articles on cervical cancer radiotherapy. METHODS: The Web of Science and Scopus databases were searched to identify the 100 most cited articles on cervical cancer radiotherapy as of September 29, 2019. Articles were ranked based on the total citations received from 2 databases. One hundred articles about radiotherapy for cervical cancer were identified. The following important information was extracted: author, journal, year and month of publication, country or region, and radiotherapy technologies. RESULTS: The 100 most cited articles on cervical cancer radiotherapy were published between 1964 and 2016, and the total citations from 2 databases ranged from 3478 to 211, including a total of 49,262 citations as of September 29, 2019. The index of citations per year ranged from 170.4 to 13.1. These articles were from 16 countries or regions, with most publications being from the United States (n = 38), followed by Austria (n = 15), Canada (n = 8), France (n = 8) and the United Kingdom (n = 7). The International Journal of Radiation Oncology, Biology, Physics produced the most articles (n = 42), followed by Radiotherapy and Oncology (n = 13), Cancer (n = 8) and Journal of Clinical Oncology (n = 7). These articles were categorized as original studies (n = 86), recommendations (n = 5), guidelines (n = 5) and reviews (n = 4). Of the 100 most cited articles, intracavitary brachytherapy (n = 50) and 3-dimensional conformal radiotherapy (n = 34) were the most commonly used treatment techniques. CONCLUSION: To the best of our knowledge, this is the first report and analysis of the most cited articles on cervical cancer radiotherapy. This bibliographic study presents the history of technological development in external radiation therapy and brachytherapy. Brachytherapy is an indispensable part of radiotherapy for cervical cancer. The International Journal of Radiation Oncology Biology Physics is the journal with the most publications related to cervical cancer radiotherapy.


Asunto(s)
Braquiterapia/métodos , Publicaciones/estadística & datos numéricos , Neoplasias del Cuello Uterino/radioterapia , Austria/epidemiología , Bibliometría , Biología/estadística & datos numéricos , Canadá/epidemiología , Bases de Datos Factuales , Femenino , Francia/epidemiología , Humanos , Oncología Médica/estadística & datos numéricos , Persona de Mediana Edad , Física/estadística & datos numéricos , Publicaciones/tendencias , Oncología por Radiación/estadística & datos numéricos , Reino Unido/epidemiología , Estados Unidos/epidemiología
11.
PLoS One ; 14(6): e0218793, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31242227

RESUMEN

Although interdisciplinarity is often touted as a necessity for modern research, the evidence on the relative impact of sectorial versus to interdisciplinary science is qualitative at best. In this paper we leverage the bibliographic data set of the American Physical Society to quantify the role of interdisciplinarity in physics, and that of talent and luck in achieving success in scientific careers. We analyze a period of 30 years (1980-2009) tagging papers and their authors by means of the Physics and Astronomy Classification Scheme (PACS), to show that some degree of interdisciplinarity is quite helpful to reach success, measured as a proxy of either the number of articles or the citations score. We also propose an agent-based model of the publication-reputation-citation dynamics which reproduces the trends observed in the APS data set. On the one hand, the results highlight the crucial role of randomness and serendipity in real scientific research; on the other, they shed light on a counterintuitive effect indicating that the most talented authors are not necessarily the most successful ones.


Asunto(s)
Estudios Interdisciplinarios , Física , Bibliometría , Simulación por Computador , Humanos , Estudios Interdisciplinarios/estadística & datos numéricos , Física/educación , Física/estadística & datos numéricos , Publicaciones/estadística & datos numéricos , Sociedades Científicas , Análisis de Sistemas , Estados Unidos
12.
Phys Med ; 67: 40-49, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31669669

RESUMEN

OBJECTIVE: Medical physics in Malaysia is still considered a young profession. This workforce survey aims to understand the status, aspirations, motivation and experiences of medical physicists (MPs) in the country. A subsection of this survey also aims to understand the role of women. METHOD: A survey was carried out between April 20 and May 30, 2018 by a working group under the Medical Physics Division of the Malaysian Institute of Physics (IFM). The survey form was designed using Google Form and sent to various public and private institutions nationwide that employed MPs registered with IFM. RESULTS: A total of 106 responses (28% men and 72% women) were analysed. This represented 30% of the medical physics workforce. Majority of them had postgraduate degrees, but their clinical training is mostly obtained on the job with no certification. The number of low-ranking female MPs was disproportionately high. MPs worked long hours and achieving work-life balance (WLB) was a challenge. Factors that improved their WLB included working close to home, having a supportive manager and flexible working hours. Most MPs aspired to become professional and mentor younger compatriots, besides contributing to patient care and research. Gender discrimination was reportedly low. CONCLUSION: Medical physics in Malaysia is growing and has a strong representation of women. In future, they would probably take over the top management from their male counterparts, whose number had stagnated. A united effort was essential to set up a proper clinical training system to train clinically qualified MPs.


Asunto(s)
Física/estadística & datos numéricos , Encuestas y Cuestionarios , Recursos Humanos/estadística & datos numéricos , Adulto , Demografía , Escolaridad , Femenino , Humanos , Malasia , Masculino , Persona de Mediana Edad , Adulto Joven
13.
Nat Hum Behav ; 3(1): 82-91, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30932052

RESUMEN

Collective memory and attention are sustained by two channels: oral communication (communicative memory) and the physical recording of information (cultural memory). Here, we use data on the citation of academic articles and patents, and on the online attention received by songs, movies and biographies, to describe the temporal decay of the attention received by cultural products. We show that, once we isolate the temporal dimension of the decay, the attention received by cultural products decays following a universal biexponential function. We explain this universality by proposing a mathematical model based on communicative and cultural memory, which fits the data better than previously proposed log-normal and exponential models. Our results reveal that biographies remain in our communicative memory the longest (20-30 years) and music the shortest (about 5.6 years). These findings show that the average attention received by cultural products decays following a universal biexponential function.


Asunto(s)
Atención , Comunicación , Cultura , Memoria , Modelos Teóricos , Bibliometría , Biografías como Asunto , Humanos , Internet/estadística & datos numéricos , Películas Cinematográficas/estadística & datos numéricos , Música , Patentes como Asunto/estadística & datos numéricos , Física/estadística & datos numéricos , Factores de Tiempo
14.
Phys Med ; 46: 104-108, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29519395

RESUMEN

PURPOSE: Though the number of women scientists is increasing over the years, studies show that they are still under-represented in leadership roles. The purpose of this work is to establish the percentage of women Medical Physicists (wMPs) that have participated in European scientific events and evaluate it as an indication of the current position of women in the field of Medical Physics in Europe and to propose possible ways to encourage their participation. MATERIALS AND METHODS: Data regarding the participants in European scientific events of Medical Physics were collected. The participants were divided into categories according to the program of the events and their gender was identified. The percentage of wMPs in each category was evaluated. RESULTS: The participation of wMPs attending courses is greater than 50%. The categories with the greatest participation are "Organizing Committees", "Chairpersons-Moderators" and "Oral Presentations". The categories with the lower participation of wMPs are "Scientific Committee", "Symposiums" and "Invited Speakers". None of wMPs were represented as "Course Directors". CONCLUSIONS: The attendance of wMPs in courses is slightly greater than average. However, wMPs do not have an equally important recognition in special invited roles in conferences. They are still under-represented in "Scientific Committees", "Invited Speakers", "Symposiums" and "Course directors". wMPs should be encouraged to participate even more actively in European conferences and the organizing committees should invite more wMPs in special roles. More studies concerning the status of female MPs in each country separately should be encouraged as they will help in understanding the position of wMPS in Europe.


Asunto(s)
Física/estadística & datos numéricos , Ciencia/organización & administración , Ciencia/estadística & datos numéricos , Europa (Continente) , Femenino , Humanos , Distribución por Sexo
16.
J Acoust Soc Am ; 122(3): 1325, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17927393

RESUMEN

A noniterative method based on the least squares technique is presented in this letter to obtain the scattering strengths of multiply scattering point targets. Benefiting from the least squares' optimization property, this new method achieves a good estimation of the scattering strengths. Compared with the noniterative method proposed in a recent paper [E. A. Marengo and F. K. Gruber "Noniterative analytical formula for inverse scattering of multiply scattering point targets," J. Acoust. Soc. Am. 120, 3782-3788 (2006)], the new method produces more accurate results in the presence of noise.


Asunto(s)
Análisis de los Mínimos Cuadrados , Música , Dinámicas no Lineales , Física/estadística & datos numéricos , Humanos , Modelos Estadísticos , Localización de Sonidos
17.
Psychol Rev ; 113(4): 700-65, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17014301

RESUMEN

In this article, the authors consider optimal decision making in two-alternative forced-choice (TAFC) tasks. They begin by analyzing 6 models of TAFC decision making and show that all but one can be reduced to the drift diffusion model, implementing the statistically optimal algorithm (most accurate for a given speed or fastest for a given accuracy). They prove further that there is always an optimal trade-off between speed and accuracy that maximizes various reward functions, including reward rate (percentage of correct responses per unit time), as well as several other objective functions, including ones weighted for accuracy. They use these findings to address empirical data and make novel predictions about performance under optimality.


Asunto(s)
Conducta de Elección , Coerción , Toma de Decisiones , Modelos Psicológicos , Física/estadística & datos numéricos , Humanos
18.
Sports Biomech ; 5(2): 197-214, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16939153

RESUMEN

In this study, we aimed to determine the direction of the spin axis and the spin rate of pitched baseballs and to estimate the associated aerodynamic forces. In addition, the effects of the spin axis direction and spin rate on the trajectory of a pitched baseball were evaluated. The trajectories of baseballs pitched by both a pitcher and a pitching machine were recorded using four synchronized video cameras (60 Hz) and were analyzed using direct linear transform (DLT) procedures. A polynomial function using the least squares method was used to derive the time-displacement relationship of the ball coordinates during flight for each pitch. The baseball was filmed immediately after ball release using a high-speed video camera (250 Hz), and the direction of the spin axis and the spin rate (omega) were calculated based on the positional changes of the marks on the ball. The lift coefficient was correlated closely with omegasinalpha (r = 0.860), where alpha is the angle between the spin axis and the pitching direction. The term omegasinalpha represents the vertical component of the velocity vector. The lift force, which is a result of the Magnus effect occurring because of the rotation of the ball, acts perpendicularly to the axis of rotation. The Magnus effect was found to be greatest when the angular and translational velocity vectors were perpendicular to each other, and the break of the pitched baseball became smaller as the angle between these vectors approached 0 degrees. Balls delivered from a pitching machine broke more than actual pitcher's balls. It is necessary to consider the differences when we use pitching machines in batting practice.


Asunto(s)
Béisbol/fisiología , Movimiento/fisiología , Física , Equipo Deportivo , Aceleración , Fenómenos Biomecánicos/métodos , Humanos , Modelos Teóricos , Física/estadística & datos numéricos , Rango del Movimiento Articular , Proyectos de Investigación , Estadística como Asunto , Análisis y Desempeño de Tareas , Temperatura
19.
Phys Med ; 31(4): 368-73, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25790723

RESUMEN

INTRODUCTION: The gender composition of the existing medical physicist (MP) workforce around the world is basically unknown. The International Organization for Medical Physics (IOMP) performed a survey in order to investigate the number of MPs in countries around the world and the percentage of women MPs compared to total number of MPs. MATERIALS AND METHODS: A simple online questionnaire prepared as a Google Forms survey asking the country, the total number of MPs, the number of female MPs and finally the gender of the person providing the data was sent in mid-March 2013 to six regional member organizations of IOMP, as well as contact points in many member countries. RESULTS: Sixty-six countries responded to the survey by mid-July 2013. Fifty two percent of those who filled the form were females, the rest males. The total number of MPs was 17,024, of which 28% were female (4807). The median values of percentages of females were 21% in the USA, 47% in Europe, 35% in Asia, 33% in Africa and 24% in Latin America. CONCLUSION: This is the first international survey that investigates the number and percentage of female MPs around the world. There are European countries that are far away from the target set by European Commission (40%) whereas in countries in the Middle East and Asia, female MPs actually outnumber males. This study is the first step in a more in-depth study that needs to be taken in near future.


Asunto(s)
Internacionalidad , Física/estadística & datos numéricos , Sociedades Científicas , Encuestas y Cuestionarios , Femenino , Humanos
20.
Neural Netw ; 16(3-4): 479-91, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12672442

RESUMEN

A microwave sky map results from a combination of signals from various astrophysical sources, such as cosmic microwave background radiation, synchrotron radiation and galactic dust radiation. To derive information about these sources, one needs to separate them from the measured maps on different frequency channels. Our insufficient knowledge of the weights to be given to the individual signals at different frequencies makes this a difficult task. Recent work on the problem led to only limited success due to ignoring the noise and to the lack of a suitable statistical model for the sources. In this paper, we derive the statistical distribution of some source realizations, and check the appropriateness of a Gaussian mixture model for them. A source separation technique, namely, independent factor analysis, has been suggested recently in the literature for Gaussian mixture sources in the presence of noise. This technique employs a three layered neural network architecture which allows a simple, hierarchical treatment of the problem. We modify the algorithm proposed in the literature to accommodate for space-varying noise and test its performance on simulated astrophysical maps. We also compare the performances of an expectation-maximization and a simulated annealing learning algorithm in estimating the mixture matrix and the source model parameters. The problem with expectation-maximization is that it does not ensure global optimization, and thus the choice of the starting point is a critical task. Indeed, we did not succeed to reach good solutions for random initializations of the algorithm. Conversely, our experiments with simulated annealing yielded initialization-independent results. The mixing matrix and the means and coefficients in the source model were estimated with a good accuracy while some of the variances of the components in the mixture model were not estimated satisfactorily.


Asunto(s)
Astronomía/métodos , Física/métodos , Astronomía/estadística & datos numéricos , Análisis Factorial , Física/estadística & datos numéricos
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