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1.
Environ Monit Assess ; 192(2): 123, 2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31955253

RESUMO

Within the last few decades, tropical coastal systems such as beaches, dunes, and mangrove forests have experienced high annual rates of loss worldwide due to natural and anthropogenic impacts. Historical remote sensing data have been used to map and monitor these fragile systems, as well as to track specific events through time. The purpose of this study was to examine coastal trends along Marismas Nacionales in Mexico, which is the largest wetland complex of the western coast of the Pacific Ocean. The opening of the Cuautla Canal in 1976 and the construction of several hydroelectric power dams have severely impacted this wetland system. Shoreline variability was estimated based on representative remote sensing images over half a century (1970 to 2019). Results indicate that, after 49 years, 805 ha of beach deposits have been lost in the Cuautla Canal and at the beach ridge region that should otherwise be an accretional coastal zone. Conversely, the southern section of the study site shows 406 ha of constant accretion during the same period due to the presence of the unobstructed San Pedro River. Our study highlights the adverse effects of engineering projects, such as inlets and hydroelectric dams throughout tropical coastal systems that have strongly depended on freshwater input from upstream rivers.


Assuntos
Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Engenharia , México , Oceano Pacífico , Tecnologia de Sensoriamento Remoto , Rios , Áreas Alagadas
2.
Bioresour Technol ; 299: 122685, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31918970

RESUMO

Different pretreatments strategies have been developed over the years mainly to enhance enzymatic cellulose degradation. In the new biorefinery era, a more holistic view on pretreatment is required to secure optimal use of the whole biomass. Hydrothermal pretreatment technology is regarded as very promising for lignocellulose biomass fractionation biorefinery and to be implemented at the industrial scale for biorefineries of second generation and circular bioeconomy, since it does not require no chemical inputs other than liquid water or steam and heat. This review focuses on the fundamentals of hydrothermal pretreatment, structure changes of biomass during this pretreatment, multiproduct strategies in terms of biorefinery, reactor technology and engineering aspects from batch to continuous operation. The treatise includes a case study of hydrothermal biomass pretreatment at pilot plant scale and integrated process design.


Assuntos
Lignina , Vapor , Biomassa , Celulose , Fracionamento Químico , Engenharia , Hidrólise
3.
Bioresour Technol ; 296: 122370, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31734058

RESUMO

Thermostability and stability in ionic liquids are essential properties of cellulases that are applied in industrial processes of bioconversion. Engineering of protein surface of endoglucanase II from Penicillium verruculosum was used to improve the enzyme thermostability and stability in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl). The engineering was based on analysis of the protein surface topography and enhanced by multiple sequence alignment and ΔΔG calculations. In the case of the thermostability, half-life time was improved in 1.3-1.6 times at 70 °C and 1.2-1.4 times at 80 °C. In the case of the stability in [Bmim]Cl, the residual activity after 72 h of incubation in the presence of [Bmim]Cl (50 g/L, 50 °C, pH 4.5) was 1.7-1.9 times greater for the tailored enzyme. The yield of reducing sugars after enzymatic hydrolysis of aspen wood pretreated with [Bmim]Cl was 10-20% higher with the tailored endoglucanase.


Assuntos
Celulase , Líquidos Iônicos , Penicillium , Engenharia , Imidazóis
4.
Nature ; 575(7781): 137-146, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31695204

RESUMO

The goal of sex and gender analysis is to promote rigorous, reproducible and responsible science. Incorporating sex and gender analysis into experimental design has enabled advancements across many disciplines, such as improved treatment of heart disease and insights into the societal impact of algorithmic bias. Here we discuss the potential for sex and gender analysis to foster scientific discovery, improve experimental efficiency and enable social equality. We provide a roadmap for sex and gender analysis across scientific disciplines and call on researchers, funding agencies, peer-reviewed journals and universities to coordinate efforts to implement robust methods of sex and gender analysis.


Assuntos
Engenharia/métodos , Engenharia/normas , Projetos de Pesquisa/normas , Projetos de Pesquisa/tendências , Ciência/métodos , Ciência/normas , Caracteres Sexuais , Fatores Sexuais , Animais , Inteligência Artificial , Feminino , Humanos , Masculino , Terapia de Alvo Molecular , Reprodutibilidade dos Testes , Tamanho da Amostra
5.
Science ; 366(6469): 1070-1071, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31780541
6.
Neural Netw ; 120: 167-203, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31610899

RESUMO

This survey samples from the ever-growing family of adaptive resonance theory (ART) neural network models used to perform the three primary machine learning modalities, namely, unsupervised, supervised and reinforcement learning. It comprises a representative list from classic to contemporary ART models, thereby painting a general picture of the architectures developed by researchers over the past 30 years. The learning dynamics of these ART models are briefly described, and their distinctive characteristics such as code representation, long-term memory, and corresponding geometric interpretation are discussed. Useful engineering properties of ART (speed, configurability, explainability, parallelization and hardware implementation) are examined along with current challenges. Finally, a compilation of online software libraries is provided. It is expected that this overview will be helpful to new and seasoned ART researchers.


Assuntos
Engenharia/métodos , Software
7.
Mar Pollut Bull ; 145: 555-563, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590823

RESUMO

The Nerbioi-Ibaizabal estuary (Bilbao, Basque Country) suffered an important input of contaminants, including metals and metalloids, between 1875 and 1975. We collected sediments in the tidal part of the river in January 2018 and measured the concentrations of 27 elements in them. At that time, two important construction works were taking place in the area: the extension of the commercial port and the opening of long semi-closed channel. Comparing the current metallic hotspots with the geographical distribution of elements in previous years (2009, 2010 and 2014) showed us that these works seem to have significantly influenced the distribution of toxic elements in the estuary, even if the critical point of the second one is still to arrive with the inundation of the connection to the mainland. Long term pollution monitoring reveals as a powerful tool to check the effects of ongoing engineering works in estuarine environments.


Assuntos
Sedimentos Geológicos/análise , Metaloides/análise , Metais/análise , Poluentes Químicos da Água/análise , Engenharia , Monitoramento Ambiental , Estuários , Limite de Detecção , Rios , Espanha
8.
Aerosp Med Hum Perform ; 90(10): 860-866, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31558194

RESUMO

BACKGROUND: The study aimed to identify factors associated with an increased likelihood of aircraft maintenance personnel reporting a fatigue-related error.METHODS: There were 966 maintenance engineering personnel (mean age = 42 yr, 98% male) who completed a survey with items on personal factors, work factors and a question asking whether during the last month they had made an error in their work due to tiredness. Logistic regression analyses were used to determine factors independently associated with making an error at work due to tiredness.RESULTS: Respondents obtained on average 7.0 h sleep and nearly half (45%) reported that they had felt close to falling asleep while driving home from work in the past 12 mo. Most respondents (70%) had received no education on strategies for coping with shift work. Among respondents, 22% agreed/strongly agreed with the statement "During the last month, I have made an error in my work due to tiredness." Unexpected roster changes independently predicted the likelihood of reporting an error in work due to tiredness and for certain groups of aircraft maintenance personnel, < 6.5 h sleep increased the odds of an error in work due to tiredness fivefold, whereas > 7.5 h sleep almost halved the odds of reporting such an error.DISCUSSION: These findings indicate the importance of stable and predictable work patterns to minimize the risk of fatigue-related errors in this safety critical environment, and also the need for education on coping with shift work to ensure the workforce are best placed to manage their sleep away from work.Signal TL, van den Berg MJ, Mulrine HM. Personal and work factors that predict fatigue-related errors in aircraft maintenance engineering. Aerosp Med Hum Perform. 2019; 90(10):860-866.


Assuntos
Medicina Aeroespacial , Aeronaves , Fadiga/fisiopatologia , Saúde do Trabalhador , Tolerância ao Trabalho Programado/fisiologia , Adolescente , Adulto , Idoso , Engenharia , Fadiga/etiologia , Feminino , Humanos , Manutenção , Masculino , Pessoa de Meia-Idade , Gestão da Segurança , Sono/fisiologia , Adulto Jovem
9.
Science ; 365(6457): 986-987, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31488676
10.
CBE Life Sci Educ ; 18(3): ar41, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31441721

RESUMO

In a previous report, we validated that a cohort of first-year undergraduates who participated in a weeklong pre-college engagement STEM Academy (SA) program were retained in science, technology, engineering, and mathematics (STEM) at a higher rate than a matched comparison group (MCG). In addition, SA students yielded increases in science identity and sense of belonging to STEM and to the university. Here, we report the ability to scale the size of the SA program to accommodate more students and replicate the previous findings with two additional cohorts. Longitudinal analysis of the 2015 and 2016 program cohorts demonstrate that both groups were retained to STEM disciplines and the university at higher rates than a MCG. To assess what underlying psychological mechanisms lead to increases in science identity and university belonging, we tested three exploratory models. These models indicate that positive changes in university and STEM belonging indirectly predict an increase in science identity. Further, positive changes in perceived family support indirectly predict increases in university belonging. Thus, through the evaluation of three different cohorts, we found robust evidence that the SA program increases sense of belonging and science identity, and these attitudinal changes promote undergraduate persistence in STEM.


Assuntos
Currículo , Engenharia/educação , Matemática/educação , Ciência/educação , Estudantes/psicologia , Tecnologia/educação , Universidades , Estudos de Coortes , Feminino , Humanos , Masculino , Projetos de Pesquisa , Adulto Jovem
12.
Biochem Mol Biol Educ ; 47(5): 506-512, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31444956

RESUMO

Supportive programming is frequently designed to increase the success of underrepresented groups in STEM. In this article, we introduce three guiding concepts from developmental psychology (developmental trajectories, developmentally appropriate practices, and holism) and explain how they relate to effective support of students from underrepresented groups. We provide examples of successful applications of these principles in classes, degree programs, and research experiences. © 2019 International Union of Biochemistry and Molecular Biology, 47(5):506-512, 2019.


Assuntos
Engenharia/educação , Matemática/educação , Ciência/educação , Estudantes/psicologia , Tecnologia/educação , Humanos , Aprendizagem
13.
Stud Health Technol Inform ; 264: 1951-1952, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438423

RESUMO

In higher education, programs in specialization in Health Informatics, Medical Informatics, Health Engineering are continuously growing. In this research, almost 1800 universities and colleges were checked in order to find related educational programs at all academic levels. Approximately 1000 academic leading degree programs in those domains have already been identified. The detailed records of the related educational programs will help to understand the current educational needs and priorities. Although, the growth of the related educational programs is not the same in each country.


Assuntos
Informática Médica , Currículo , Engenharia , Universidades
15.
Nat Commun ; 10(1): 3895, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467280

RESUMO

Understanding human mobility is crucial for applications such as forecasting epidemic spreading, planning transport infrastructure and urbanism in general. While, traditionally, mobility information has been collected via surveys, the pervasive adoption of mobile technologies has brought a wealth of (real time) data. The easy access to this information opens the door to study theoretical questions so far unexplored. In this work, we show for a series of worldwide cities that commuting daily flows can be mapped into a well behaved vector field, fulfilling the divergence theorem and which is, besides, irrotational. This property allows us to define a potential for the field that can become a major instrument to determine separate mobility basins and discern contiguous urban areas. We also show that empirical fluxes and potentials can be well reproduced and analytically characterized using the so-called gravity model, while other models based on intervening opportunities have serious difficulties.


Assuntos
Modelos Biológicos , Amplitude de Movimento Articular , Transportes , Telefone Celular , Cidades , Simulação por Computador , Bases de Dados Factuais , Engenharia , Previsões , Gravitação , Humanos , Londres , Densidade Demográfica , Dinâmica Populacional , Transportes/estatística & dados numéricos
17.
CBE Life Sci Educ ; 18(3): mr3, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31469623

RESUMO

There has been a recent push for greater collaboration across the science, technology, engineering, and mathematics (STEM) fields in discipline-based education research (DBER). The DBER fields are unique in that they require a deep understanding of both disciplinary content and educational research. DBER scholars are generally trained and hold professional positions in discipline-specific departments. The professional societies with which DBER scholars are most closely aligned are also often discipline specific. This frequently results in DBER researchers working in silos. At the same time, there are many cross-cutting issues across DBER research in higher education, and DBER researchers across disciplines can benefit greatly from cross-disciplinary collaborations. This report describes the Breaking Down Silos working meeting, which was a short, focused meeting intentionally designed to foster such collaborations. The focus of Breaking Down Silos was institutional transformation in STEM education, but we describe the ways the overall meeting design and structure could be a useful model for fostering cross--disciplinary collaborations around other research priorities of the DBER community. We describe our approach to meeting recruitment, premeeting work, and inclusive meeting design. We also highlight early outcomes from our perspective and the perspectives of the meeting participants.


Assuntos
Engenharia/educação , Estudos Interdisciplinares , Matemática/educação , Pesquisa , Ciência/educação , Tecnologia/educação , Congressos como Assunto , Comportamento Cooperativo , Humanos
18.
CBE Life Sci Educ ; 18(3): ar35, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31397651

RESUMO

Gender gaps in exam scores or final grades are common in introductory college science and engineering classrooms, with women underperforming relative to men with the same admission test scores or college grade point averages. After failing to close a historically documented gender gap in a large introductory biology course using interventions targeted at training a growth mindset, we implemented interventions designed to reduce student test anxiety. We combined evidence-based exercises based on expressive writing and on reappraising physiological arousal. We also used a valid measure to quantify test anxiety at the start and end of the course. This instrument measures an individual's self-declared or perceived test anxiety-also called trait anxiety-but not the immediate or "state" anxiety experienced during an actual exam. Consistent with previous reports in the literature, we found that women in this population declared much higher test anxiety than men and that students who declared higher test anxiety had lower exam scores than students who declared lower test anxiety. Although the test anxiety interventions had no impact on the level of self-declared trait anxiety, they did significantly increase student exam performance. The treatment benefits occurred in both men and women. These data suggest that 1) a combination of interventions based on expressive writing and reappraising physiological arousal can be a relatively easy manner to boost exam performance in a large-enrollment science, technology, engineering, and mathematics (STEM) course and encourage emotion regulation; 2) women are more willing than men to declare that they are anxious about exams, but men and women may actually experience the same level of anxiety during the exam itself; and 3) women are underperforming in STEM courses for reasons other than gender-based differences in mindset or test anxiety.


Assuntos
Ansiedade/psicologia , Currículo , Avaliação Educacional , Engenharia/educação , Matemática/educação , Ciência/educação , Estudantes/psicologia , Tecnologia/educação , Feminino , Humanos , Masculino , Fatores Sexuais , Universidades , Redação
20.
Nat Rev Genet ; 20(9): 501, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31270438
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