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1.
Materials (Basel) ; 17(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38541487

RESUMO

Scalmalloy® is an Al-Mg-Sc-Zr-based alloy specifically developed for additive manufacturing (AM). This alloy is designed for use with a direct aging treatment, as recommended by the manufacturer, rather than with a multistep treatment, as often seen in conventional manufacturing. Most work with Scalmalloy® is conducted using powder bed rather than powder-fed processes. This investigation seeks to fill this knowledge gap and expand beyond single-step aging to promote an overall balanced AM-fabricated component. For this study, directed energy deposition (DED)-fabricated Scalmalloy® components were subjected to low-temperature treatments to minimize residual stresses inherent in the material due to the layer-by-layer build process. X-ray diffraction (XRD) indicated the possibility of stress minimization while reducing the detriment to mechanical strength through lower temperature treatments. Microstructural analyses consisting of energy dispersion spectroscopy (EDS) and electron backscatter diffraction (EBSD) revealed the presence of grain growth detrimentally affecting the strength and elongation made possible by very small grains inherent to AM and rapid solidification. Tensile testing determined that treatment at 175 °C for 1 h provides the best relief from the existing residual stresses; however, this is accompanied by a diminishment in the yield and tensile strength of 19 and 9.5%, respectively. It is noted that treatment at 175 °C for 2 h did not provide as great of a decrease in residual stresses, theorized to be the result of grain growth and other strengthening mechanisms further stressing the structure; however, the residual stresses are still significantly diminished compared with the as-built condition. Furthermore, a minimal reduction of the tensile strengths indicates the possibility of finding a balance between property diminishment and stress state through the work proposed here.

2.
Top Cogn Sci ; 16(1): 54-70, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37962526

RESUMO

Great storytelling takes us on a journey the way ordinary reality rarely does. But what exactly do we mean by this "journey?" Recently, literary theorist Karin Kukkonen proposed that storytelling is "probability design:" the art of giving an audience pieces of information bit by bit, to craft the journey of their changing beliefs about the fictional world. A good "probability design" choreographs a delicate dance of certainty and surprise in the reader's mind as the story unfolds from beginning to end. In this paper, we computationally model this conception of storytelling. Building on the classic Bayesian inverse planning model of human social cognition, we treat storytelling as inverse inverse planning: the task of choosing actions to manipulate an inverse planner's inferences, and therefore a human audience's beliefs. First, we use an inverse inverse planner to depict social and physical situations, and present behavioral studies indicating that inverse inverse planning produces more expressive behavior than ordinary "naïve planning." Then, through a series of examples, we demonstrate how inverse inverse planning captures many storytelling elements from first principles: character, narrative arcs, plot twists, irony, flashbacks, and deus ex machina are all naturally encoded in the flexible language of probability design.


Assuntos
Comunicação , Narração , Humanos , Teorema de Bayes , Idioma
3.
Ann Emerg Med ; 82(2): 238-239, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37479406
4.
Appl Res Qual Life ; 18(1): 115-162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37032789

RESUMO

To inhibit the spread of COVID-19 Public health officials stress, and governments often require, restrictions on social interaction ("social distancing"). While the medical benefits are clear, important questions remain about these measures' downsides: How bitter is this medicine? Ten large non-probability internet-based surveys between April and November 2020, weighted statistically to reflect the US population in age, education, and religious background and excluding respondents who even occasionally role-played rather than giving their own true views; N = 6,223. Pre-epidemic data from 2017-2019, N = 4,032. Reliable multiple-item scales including subjective wellbeing (2 European Quality of Life Survey items, Cronbach's alpha = .85); distancing attitudes (5 items, alpha = .87); distancing behavior e.g., standing 6' apart in public (5 items, alpha = .80); emotional cost of distancing and restrictions on social interaction (8-12 items, alpha = .94); and an extensive suite of controls (19 variables). Descriptive statistics, OLS regression, structural equation models. Subjective wellbeing is greater for those who approve of distancing, for those who practice distancing, and particularly for those whose distancing attitudes and behavior are congruent, either both in favor or both opposed (multiplicative interaction). The emotional cost of distancing is strongly tied to wellbeing and is heterogeneous, with some disliking distancing much more than others. An SEM model suggests causality: that emotional costs strongly reduce wellbeing but not vice-versa. During the epidemic, COVID issues constitute two of the top 5 influences on wellbeing, behind only subjective health and religious belief and tied with income. All this is net of family background, religious origins, age, ethnicity, race, gender, rural residence, education, occupational status, marriage, unemployment, income, health, religion, and political party. Supplementary Information: The online version contains supplementary material available at 10.1007/s11482-023-10149-0.

5.
Ann Emerg Med ; 81(1): 70-72, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334955

RESUMO

We report a case of cardioversion that was successfully performed on a patient during cold water immersion. The patient deteriorated into unstable ventricular tachycardia while being treated for heatstroke. We elected to perform synchronized cardioversion without first removing the patient from the immersion body bag. The patient survived and was discharged neurologically intact on hospital day 5. There were no evident deleterious effects to the staff, the patient, or the equipment. To our knowledge, this is the first case report in the literature demonstrating the electrical cardioversion of a patient immersed in water.


Assuntos
Golpe de Calor , Taquicardia Ventricular , Humanos , Cardioversão Elétrica , Imersão , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/terapia , Golpe de Calor/complicações , Golpe de Calor/terapia , Água
6.
Soc Sci Res ; 94: 102446, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648680

RESUMO

In formulating views of just reward for high-status and low-status work, do ordinary citizens take cues from their nation's public stance on income inequality as institutionally embedded in their welfare state, i.e. their social welfare and labor market policies, their "welfarism"? How large a morally correct earnings gap flows from that? Our multilevel analyses (fixed effects, random intercepts) replicate prior research on the impact of individual characteristics and socioeconomic development. They open new territory with the discovery that public opinion on legitimate/just earnings of high-status occupations aligns moderately strongly with welfarism, ceteris paribus, with welfare state citizens advocating lower pay for the elite but not higher pay for working-class occupations: The welfare state is not (or no longer) a matter of helping the poor but instead of bringing down the elite, "cutting down the tall poppies". Data: World Inequality Study v2.1: 30 countries, 71 surveys, and over 88,000 individuals.


Assuntos
Renda , Ocupações , Humanos , Seguridade Social , Fatores Socioeconômicos
7.
J Educ Teach Emerg Med ; 6(3): S1-S32, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37465078

RESUMO

Audience: This scenario was developed to educate junior and senior emergency medicine (EM) residents. It can also be cut short to be used for 4th year EM bound medical students. Introduction: Meningococcal meningitis is a devastating disease that can cause severe neurologic sequelae if not diagnosed early and treated appropriately. In 2017, Centers for Disease Control reports a rate of 350 cases (0.11 cases per 100,000) which makes it an extremely rare disease. The highest reported rate is under the age of 1 (0.69 in 100,000) with second peak in adolescents and young adults between the ages of 16 and 23 (0.29 in 100,000) and third peak in patients above the age of 80 (0.49 in 100,000).1 The presentation for bacterial meningitis includes neck stiffness, fever, vomiting, photophobia, positive Kernig and Brudzinski's sign, and lethargy. In addition, 80% patients with meningococcal meningitis have rash during some stage of their disease.2 A feared and rare complication of severe meningococcal disease is Waterhouse-Friderichsen Syndrome (WFS) which carries a high mortality rate of 20%. Therefore, early diagnosis and rapid management of meningococcal disease is highly imperative.3 This simulation case was written to demonstrate the presentation of meningococcal meningitis and to discuss the management of WFS. Educational Objectives: By the end of this simulation session, learners will be able to: (1) manage a patient with altered mental status (AMS) with fever while maintaining a broad differential diagnosis, (2) recognize the risk factors for meningococcal meningitis, (3) manage a patient with worsening shock and perform appropriate resuscitation, (4) develop a differential diagnosis for thrombocytopenia and elevated international normalized ratio (INR) in an altered febrile hypotensive patient with rash, (5) manage the bleeding complications from WFS, (6) discuss the complications of meningococcal meningitis including WFS, and (7) review when meningitis prophylaxis is given. Educational Methods: This session was conducted using high-fidelity simulation. It was immediately followed by an in-depth debriefing session. The session was conducted on a total of 9 EM residents from various levels of training who actively participated during the case and 25 residents who were observers. There was 1 simulation instructor running the session and 1 simulation technician who acted as a nurse. Research Methods: After the simulation and debriefing session was complete, an online survey was sent via surveymonkey.com to all the learners. The survey collected responses to the following questions: (1) the case was believable, (2) the case had right amount of complexity, (3) the case helped in improving medical knowledge and patient care, (4) the simulation environment gave me a real-life experience and, (5) the debriefing session after simulation helped improve my knowledge. A ten-item Likert scale was used to collect the responses. Results: Ten learners responded to the survey. One hundred percent of them either agreed or strongly agreed that the case was beneficial in learning and improving patient care. They also agreed that it helped in improving medical knowledge. The post-session debrief was found to be very helpful by all the learners.. Discussion: This high-fidelity simulation case was not only cost-effective but also was very helpful in teaching EM residents how to manage a patient with meningococcal meningitis and WFS. The case was started with the patient presenting with altered mental status and fever, and as the case unfolded, mental status and shock worsened allowing the learners to intubate and resuscitate. Overall, learners also found the discussion of prophylaxis valuable. Topics: Meningitis, altered mental status, medical simulation, infectious disease, neurology, septic shock, Waterhouse-Friderichsen Syndrome, hematology.

8.
J Alzheimers Dis ; 78(1): 291-308, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32955458

RESUMO

BACKGROUND: The European PharmaCog study (http://www.pharmacog.org) has reported a reduction in delta (1-6 Hz) electroencephalographic (EEG) power (density) during cage exploration (active condition) compared with quiet wakefulness (passive condition) in PDAPP mice (hAPP Indiana V717F mutation) modeling Alzheimer's disease (AD) amyloidosis and cognitive deficits. OBJECTIVE: Here, we tested the reproducibility of that evidence in TASTPM mice (double mutation in APP KM670/671NL and PSEN1 M146V), which develop brain amyloidosis and cognitive deficits over aging. The reliability of that evidence was examined in four research centers of the PharmaCog study. METHODS: Ongoing EEG rhythms were recorded from a frontoparietal bipolar channel in 29 TASTPM and 58 matched "wild type" C57 mice (range of age: 12-24 months). Normalized EEG power was calculated. Frequency and amplitude of individual delta and theta frequency (IDF and ITF) peaks were considered during the passive and active conditions. RESULTS: Compared with the "wild type" group, the TASTPM group showed a significantly lower reduction in IDF power during the active over the passive condition (p < 0.05). This effect was observed in 3 out of 4 EEG recording units. CONCLUSION: TASTPM mice were characterized by "poor reactivity" of delta EEG rhythms during the cage exploration in line with previous evidence in PDAPP mice. The reliability of that result across the centers was moderate, thus unveiling pros and cons of multicenter preclinical EEG trials in TASTPM mice useful for planning future studies.


Assuntos
Doença de Alzheimer/genética , Eletroencefalografia/métodos , Precursor de Proteína beta-Amiloide/genética , Amiloidose , Animais , Encéfalo/metabolismo , Disfunção Cognitiva , Camundongos , Camundongos Transgênicos , Movimento , Reprodutibilidade dos Testes , Vigília
9.
J Am Chem Soc ; 142(10): 4631-4638, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046478

RESUMO

Marine mussels secret catechol-containing adhesive proteins that enable these organisms to bind to various surfaces underwater. Synthetic mimics of these proteins have been created to function as adhesives and coatings for a wide range of applications. Here, we demonstrated the use of in situ electrical field stimulation to deactivate the adhesive property of catechol-containing adhesive that is in direct contact with a surface. Johnson-Kendall-Roberts (JKR) contact mechanics test was performed using a titanium (Ti) sphere in the presence of a pH 7.5 aqueous buffer. The Ti sphere also served as a conductive electrode for applying electricity to the adhesive, while a platinum (Pt) wire served as the counter electrode. Work of adhesion (Wadh) decreased with increased levels of applied voltage and current, exposure time to the applied electricity, and salt concentration of the interfacial buffer. Application of 9 V for 1 min completely deactivated the adhesive. UV-vis diffuse reflectance spectra and tracking of catechol oxidation byproduct, hydrogen peroxide, confirmed that catechol was oxidized as a result of applied electricity. Contact mechanics testing further confirmed that the Young's modulus of the adhesive increased by nearly 4 folds at the interface as a result of oxidative cross-linking, even though the modulus of the bulk of the adhesive was unaffected by applied electricity. The accumulation of hydroxyl ions near the cathode increased the local solution pH, which promoted oxidation-induced cross-linking of catechol and subsequently decreased its adhesive property. Tuning adhesive properties through in situ electrochemical oxidation provides on-demand control over the adhesive, which will potentially add another dimension in designing synthetic mimics of mussel adhesive proteins.


Assuntos
Adesivos/química , Catecóis/química , Módulo de Elasticidade , Eletroquímica/instrumentação , Eletroquímica/métodos , Eletrodos , Oxirredução , Platina/química , Titânio/química
10.
Front Sociol ; 5: 576827, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33869503

RESUMO

The protracted COVID-19 crisis provides a new social niche in which new inequalities can emerge. We provide predictions about one such new inequality using the logic of Status Construction Theory (SCT). SCT, rooted in Expectations State Theory and from there developed by Ridgeway and colleagues, proposes general hypotheses about how new inequalities arise through process of interaction at the individual level: an unordered categorical difference becomes attached to a cultural value that gives one category more value than the other; social scripts concerning it emerge; small elements of assertion and deference creep into more and more encounters that an individual participates in, hears about through networks, and learns about via social and conventional media. The categorical difference begins to morph into a hierarchical status distinction. Through these mechanisms, individuals develop "status beliefs" that most people in their communities endorse the status distinction. Although they may or may not endorse the distinction personally, they believe that most people do so and they find that the path of least resistance socially is to enact the scripts that affirm the higher status/prestige of the favored group. We apply Status Construction Theory to the categorical difference between Antibody Positives (who have been tested for IgG antibodies) and Others (everybody else). Using the general logic of SCT and specifically developing applications of its key propositions, we predict that the categorical difference between Antibody Positives and Others will transition to a status distinction and propose testable, falsifiable hypotheses about each step of the process.

11.
Front Sociol ; 4: 12, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33869339

RESUMO

Public attitudes toward immigrants in the UK, especially prejudice against them, form a strong theme in retrospective media postmortems emphasizing the uniqueness of Brexit, yet similarly hostile public opinion on immigrants forms a recurrent theme in populist politics in many European Union nations. Indeed, if UK residents are not uniquely hostile, then the UK's exit from the EU may be only the first symptom of proliferating conflicts over immigration that will plague EU nations in future years. A well-established symptom (or consequence) of prejudice-aversion to outgroups as a neighbors-shows that prejudice against immigrants, other races, Muslims, Hindus, Jews, and Gypsies are all relatively low in the UK. This is as expected from the general decline of prejudice and social distance with socioeconomic development, demonstrated here in broad perspective across many countries. Indeed, UK residents are about as prejudiced against each of these ethno-religious outgroups as are their peers in other advanced EU and English-speaking nations, and much less prejudiced than their peers in less prosperous countries. Confirmatory factor analysis supports the view that a single latent ethno-religious prejudice generates all these specific prejudices, so it is not specific experiences with any one of these groups, nor their specific attributes, that are the wellspring of this deep-seated underlying prejudice. Replication using other measures of prejudice and another cross-national dataset confirms these findings. Data are from the pooled World and European Values Surveys (over 450,000 individuals, 300 surveys, and 100 nations for this analysis) and from the well-known European Quality of Life surveys. Analysis is by descriptive, multilevel (random intercept, fixed effects), and structural equation methods.

12.
Soc Sci Res ; 77: 1-15, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30466867

RESUMO

A growing body of evidence supports the contention of scholarly culture theory that immersing children in book-oriented environments benefits their later educational achievement, attainment and occupational standing. These findings have been interpreted as suggesting that book-oriented socialization, indicated by home library size, equips youth with life-long tastes, skills and knowledge. However, to date, this has not been directly assessed. Here, we document advantageous effects of scholarly culture for adult literacy, adult numeracy, and adult technological problem solving. Growing up with home libraries boosts adult skills in these areas beyond the benefits accrued from parental education or own educational or occupational attainment. The effects are loglinear, with greatest returns to the growth in smaller libraries. Our evidence comes from regressions with balanced repeated replicate weights estimated on data from 31 societies which participated in the Programme for the International Assessment of Adult Competencies (PIAAC) between 2011 and 2015.

13.
Acta Biomater ; 83: 109-118, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30541699

RESUMO

Microgels that can generate antipathogenic levels of hydrogen peroxide (H2O2) through simple rehydration in solutions with physiological pH are described herein. H2O2 is a widely used disinfectant but the oxidant is hazardous to store and transport. Catechol, an adhesive moiety found in mussel adhesive proteins, was incorporated into microgels, which generated 1-5 mM of H2O2 for up to four days as catechol autoxidized. The sustained release of low concentrations of H2O2 was antimicrobial against both gram-positive (Staphylococcus epidermidis) and gram-negative (Escherichia coli) bacteria and antiviral against both non-enveloped porcine parvovirus (PPV) and enveloped bovine viral diarrhea virus (BVDV). The amount of released H2O2 is several orders of magnitude lower than H2O2 concentration previously reported for antipathogenic activity. Most notably, these microgels reduced the infectivity of the more biocide resistant non-envelope virus by 3 log reduction value (99.9% reduction in infectivity). By controlling the oxidation state of catechol, microgels can be repeatedly activated and deactivated for H2O2 generation. These microgels do not contain a reservoir for storing the reactive H2O2 and can potentially function as a lightweight and portable dried powder source for the disinfectant for a wide range of applications. STATEMENT OF SIGNIFICANCE: Researchers have designed bioadhesives and coatings using the adhesive moiety catechol to mimic the strong adhesion capability of mussel adhesive proteins. During catechol autoxidation, hydrogen peroxide (H2O2) is generated as a byproduct. Here, catechol was incorporated into microgels, which can generate millimolar levels of H2O2 by simply hydrating the microgels in a solution with physiological pH. The sustained release of H2O2 was both antimicrobial and antiviral, inactivating even the more biocide resistant non-enveloped virus. These microgels can be repeatedly activated and deactivated for H2O2 generation by incubating them in solutions with different pH. This simplicity and recyclability will enable this biomaterial to function as a lightweight and portable source for the disinfectant for a wide range of applications.


Assuntos
Vírus da Diarreia Viral Bovina/crescimento & desenvolvimento , Desinfetantes , Escherichia coli/crescimento & desenvolvimento , Peróxido de Hidrogênio , Parvovirus Suíno/crescimento & desenvolvimento , Staphylococcus epidermidis/crescimento & desenvolvimento , Desinfetantes/química , Desinfetantes/farmacologia , Géis , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia
14.
Front Hum Neurosci ; 12: 400, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30386221

RESUMO

In the last decade advances in human neuroscience have identified the critical importance of time in creating long-term memories. Circadian neuroscience has established biological time functions via cellular clocks regulated by photosensitive retinal ganglion cells and the suprachiasmatic nuclei. Individuals have different circadian clocks depending on their chronotypes that vary with genetic, age, and sex. In contrast, social time is determined by time zones, daylight savings time, and education and employment hours. Social time and circadian time differences can lead to circadian desynchronization, sleep deprivation, health problems, and poor cognitive performance. Synchronizing social time to circadian biology leads to better health and learning, as demonstrated in adolescent education. In-day making memories of complex bodies of structured information in education is organized in social time and uses many different learning techniques. Research in the neuroscience of long-term memory (LTM) has demonstrated in-day time spaced learning patterns of three repetitions of information separated by two rest periods are effective in making memories in mammals and humans. This time pattern is based on the intracellular processes required in synaptic plasticity. Circadian desynchronization, sleep deprivation, and memory consolidation in sleep are less well-understood, though there has been considerable progress in neuroscience research in the last decade. The interplay of circadian, in-day and sleep neuroscience research are creating an understanding of making memories in the first 24-h that has already led to interventions that can improve health and learning.

15.
Biomacromolecules ; 19(5): 1416-1424, 2018 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-29125290

RESUMO

Adhesive hydrogels were prepared by copolymerizing dopamine methacrylamide with either acrylic acid (AAc) or N-(3-aminopropyl)methacrylamide hydrochloride (APMH). The effect of incorporating the anionic and cationic side chains on the oxidation state of catechol was characterized using the FOX assay to track the production of hydrogen peroxide byproduct generated during the autoxidation of catechol, and the interfacial binding property of the adhesive was determined by performing Johnson-Kendall-Roberts contact mechanics tests tested over a wide range of pH values (pH 3.0-9.0). The ionic species contributed to interfacial binding to surfaces with the opposite charge with measured work of adhesion values that were comparable to or in some cases higher than those of catechol. Addition of AAc minimized the oxidation of catechol even at a pH of 8.5 and correspondingly preserved the elevated adhesive property of catechol to both quartz and amine-functionalized surfaces. However, AAc lost its buffering capacity at pH 9.0, and catechol was oxidized at this pH. On the other hand, catechol formed a cohesive covalent bond with the network-bound amine side chain of APMH at basic pH, which interfered with the interfacial binding capability of APMH and the catechol.


Assuntos
Adesivos/química , Catecóis/química , Hidrogéis/química , Acrilamidas/química , Cátions/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Oxirredução , Quartzo/química
16.
Front Hum Neurosci ; 11: 588, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29276481

RESUMO

While many studies have shown the benefits of later school starts, including better student attendance, higher test scores, and improved sleep duration, few have used starting times later than 9:00 a.m. Here we report on the implementation and impact of a 10 a.m. school start time for 13 to 16-year-old students. A 4-year observational study using a before-after-before (A-B-A) design was carried out in an English state-funded high school. School start times were changed from 8:50 a.m. in study year 0, to 10 a.m. in years 1-2, and then back to 8:50 a.m. in year 3. Measures of student health (absence due to illness) and academic performance (national examination results) were used for all students. Implementing a 10 a.m. start saw a decrease in student illness after 2 years of over 50% (p < 0.0005 and effect size: Cohen's d = 1.07), and reverting to an 8:50 a.m. start reversed this improvement, leading to an increase of 30% in student illness (p < 0.0005 and Cohen's d = 0.47). The 10:00 a.m. start was associated with a 12% increase in the value-added number of students making good academic progress (in standard national examinations) that was significant (<0.0005) and equivalent to 20% of the national benchmark. These results show that changing to a 10:00 a.m. high school start time can greatly reduce illness and improve academic performance. Implementing school start times later than 8:30 a.m., which may address the circadian delay in adolescents' sleep rhythms more effectively for evening chronotypes, appears to have few costs and substantial benefits.

17.
Front Hum Neurosci ; 11: 188, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28469566

RESUMO

University days generally start at fixed times in the morning, often early morning, without regard to optimal functioning times for students with different chronotypes. Research has shown that later starting times are crucial to high school students' sleep, health, and performance. Shifting the focus to university, this study used two new approaches to determine ranges of start times that optimize cognitive functioning for undergraduates. The first is a survey-based, empirical model (SM), and the second a neuroscience-based, theoretical model (NM). The SM focused on students' self-reported chronotype and times they feel at their best. Using this approach, data from 190 mostly first and second year university students were collected and analyzed to determine optimal times when cognitive performance can be expected to be at its peak. The NM synthesized research in sleep, circadian neuroscience, sleep deprivation's impact on cognition, and practical considerations to create a generalized solution to determine the best learning hours. Strikingly the SM and NM results align with each other and confirm other recent research in indicating later start times. They add several important points: (1) They extend our understanding by showing that much later starting times (after 11 a.m. or 12 noon) are optimal; (2) Every single start time disadvantages one or more chronotypes; and (3) The best practical model may involve three alternative starting times with one afternoon shared session. The implications are briefly considered.

18.
Soc Sci Res ; 62: 1-23, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28126092

RESUMO

Income inequality has been contentious for millennia, a source of political conflict for centuries, and is now widely feared as a pernicious "side effect" of economic progress. But equality is only a means to an end and so must be evaluated by its consequences. The fundamental question is: What effect does a country's level of income inequality have on its citizens' quality of life, their subjective well-being? We show that in developing nations inequality is certainly not harmful but probably beneficial, increasing well-being by about 8 points out of 100. This may well be Kuznets's inverted "U": In the earliest stages of development some are able to move out of the (poorly paying) subsistence economy into the (better paying) modern economy; their higher pay increases their well-being while simultaneously increasing inequality. In advanced nations, income inequality on average neither helps nor harms. Estimates are from random-intercept fixed-effects multi-level models, confirmed by over four dozen sensitivity tests. Data are from the pooled World Values/European Values Surveys, Waves 1 to 5 with 169 representative national samples in 68 nations, 1981 to 2009, and over 200,000 respondents, replicated and extended in the European Quality of Life Surveys.

19.
Soc Sci Res ; 62: 39-74, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28126114

RESUMO

Based on earlier, mainly aggregate analyses, conventional wisdom previously held that income inequality reduces happiness. But aggregate models consistently yield misleading results in this domain, substantially because of intractable problems of sample size, confounding omitted variables, and conditional effects differing between poor developing nations, rich advanced nations, and nations in transition from Communism. Based on more recent evidence, scholarly views are beginning to merge on a consensus that national income inequality is irrelevant to individuals' subjective well-being in advanced nations and normal times, as shown by multi-level models with appropriate controls (including socioeconomic development, an engine of happiness and foe of inequality). For developing nations, consensus is not as strong, but the bulk of the evidence indicates a neutral to positive effect for inequality. Building on this foundation, this paper provides exploratory analyses to stimulate future research, extending our understanding of the social psychological and cultural forces that generate these results; dissects changes over time and expectations for the future; and addresses the possibility that inequality may reduce well-being in extraordinary circumstances and for particular groups - for example creating differences in formerly Communist nations between the political left and the right, and between older and younger cohorts.


Assuntos
Felicidade , Renda , Atitude , Humanos , Política , Fatores Socioeconômicos
20.
Neurobiol Aging ; 49: 20-30, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27728831

RESUMO

Resting state electroencephalographic (EEG) rhythms reflect the fluctuation of cortical arousal and vigilance in a typical clinical setting, namely the EEG recording for few minutes with eyes closed (i.e., passive condition) and eyes open (i.e., active condition). Can this procedure be back-translated to C57 (wild type) mice for aging studies? On-going EEG rhythms were recorded from a frontoparietal bipolar channel in 85 (19 females) C57 mice. Male mice were subdivided into 3 groups: 25 young (4.5-6 months), 18 middle-aged (12-15 months), and 23 old (20-24 months) mice to test the effect of aging. EEG power density was compared between short periods (about 5 minutes) of awake quiet behavior (passive) and dynamic exploration of the cage (active). Compared with the passive condition, the active condition induced decreased EEG power at 1-2 Hz and increased EEG power at 6-10 Hz in the group of 85 mice. Concerning the aging effects, the passive condition showed higher EEG power at 1-2 Hz in the old group than that in the others. Furthermore, the active condition exhibited a maximum EEG power at 6-8 Hz in the former group and 8-10 Hz in the latter. In the present conditions, delta and theta EEG rhythms reflected changes in cortical arousal and vigilance in freely behaving C57 mice across aging. These changes resemble the so-called slowing of resting state EEG rhythms observed in humans across physiological and pathological aging. The present EEG procedures may be used to enhance preclinical phases of drug discovery in mice for understanding the neurophysiological effects of new compounds against brain aging.


Assuntos
Envelhecimento/fisiologia , Nível de Alerta/fisiologia , Córtex Cerebral/fisiologia , Eletroencefalografia , Animais , Descoberta de Drogas , Feminino , Masculino , Camundongos Endogâmicos C57BL , Descanso/fisiologia , Vigília/fisiologia
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