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1.
Sci Adv ; 5(10): eaaw5461, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31681837

RESUMO

Since the inauguration of Donald Trump, there has been substantial and ongoing protest against the Administration. Street demonstrations are some of the most visible forms of opposition to the Administration and its policies. This article reviews the two most central methods for studying street protest on a large scale: building comprehensive event databases and conducting field surveys of participants at demonstrations. After discussing the broader development of these methods, this article provides a detailed assessment of recent and ongoing projects studying the current wave of contention. Recommendations are offered to meet major challenges, including making data publicly available in near real time, increasing the validity and reliability of event data, expanding the scope of crowd surveys, and integrating ongoing projects in a meaningful way by building new research infrastructure.

2.
AJS ; 121(2): 475-510, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26594715

RESUMO

The authors argue that group threat is a key driver of the adoption of new and controversial policies. Conceptualizing threat in spatial terms, they argue that group threat is activated through the joint occurrence of (1) proximity to threatening groups and (2) the population density of threatened groups. By analyzing the adoption of county and state "dry laws" banning alcohol from 1890 to 1919, they first show that prohibition victories were driven by the relative strength of supportive constituencies such as native whites and rural residents, vis-à-vis opponents such as Irish, Italian, or German immigrants or Catholics. Second, they show that threat contributed to prohibition victories: counties bordering large immigrant or urban populations, which did not themselves contain similar populations, were more likely to adopt dry laws. Threat arises primarily from interactions between spatially proximate units at the local level, and therefore higher-level policy change is not reducible to the variables driving local policy.


Assuntos
Consumo de Bebidas Alcoólicas/história , Política , Consumo de Bebidas Alcoólicas/legislação & jurisprudência , Consumo de Bebidas Alcoólicas/prevenção & controle , Etnicidade , História do Século XIX , História do Século XX , Humanos , Densidade Demográfica , População Rural , Estados Unidos , População Urbana
3.
Opt Express ; 23(26): 33705-12, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26832033

RESUMO

An adaptive optics (AO) testbed was integrated to the Optical PAyload for Lasercomm Science (OPALS) ground station telescope at the Optical Communications Telescope Laboratory (OCTL) as part of the free space laser communications experiment with the flight system on board the International Space Station (ISS). Atmospheric turbulence induced aberrations on the optical downlink were adaptively corrected during an overflight of the ISS so that the transmitted laser signal could be efficiently coupled into a single mode fiber continuously. A stable output Strehl ratio of around 0.6 was demonstrated along with the recovery of a 50 Mbps encoded high definition (HD) video transmission from the ISS at the output of the single mode fiber. This proof of concept demonstration validates multi-Gbps optical downlinks from fast slewing low-Earth orbiting (LEO) spacecraft to ground assets in a manner that potentially allows seamless space to ground connectivity for future high data-rates network.

4.
Mater Sci Eng C Mater Biol Appl ; 45: 333-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25491836

RESUMO

The human vocal fold is a complex structure made up of distinct layers that vary in cellular and extracellular matrix composition. Elucidating the mechanical properties of vocal fold tissues is critical for the study of both acoustics and biomechanics of voice production, and essential in the context of vocal fold injury and repair. Both quasistatic and dynamic behavior in the 10-300 Hz range was explored in this preliminary investigation. The resultant properties of the lamina propria were compared to that of the nearby thyroarytenoid muscle. Er, quantified via quasistatic testing of the lamina propria, was 609±138 MPa and 758±142 MPa in the muscle (p=0.001). E' of the lamina propria as determined by dynamic testing was 790±526 MPa compared to 1061±928 MPa in the muscle. Differences in E' did not achieve statistical significance via linear mixed effect modeling between the tissue types (p=0.95). In addition, frequency dependence was not significant (p=0.18).


Assuntos
Prega Vocal/fisiologia , Animais , Fenômenos Biomecânicos , Mucosa/fisiologia , Músculos/fisiologia , Coelhos , Cicatrização/fisiologia
5.
JAMA Otolaryngol Head Neck Surg ; 140(3): 192-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24481258

RESUMO

IMPORTANCE: Current approaches to the diagnosis and subsequent management of specific voice disorders vary widely among primary care physicians (PCPs). In addition, sparse literature describes current primary care practice patterns concerning empirical treatment for vocal disorders. OBJECTIVE: To examine how PCPs manage patients with dysphonia, especially with regard to laryngopharyngeal reflux. DESIGN, SETTING, AND PARTICIPANTS: Prospective, questionnaire-based study by an academic laryngology practice among academic PCPs from all major US geographic regions. MAIN OUTCOMES AND MEASURES: A 16-question web-based survey, distributed via e-mail, concerning management and possible empirical treatment options for patients with dysphonia. RESULTS: Of 2441 physicians who received the e-mail broadcast, 314 (12.9%) completed the survey. Among those who completed the survey, 46.3% were family practitioners, 46.5% were trained in internal medicine, and 7.2% identified as specialists. Among all respondents, 64.0% preferred to treat rather than immediately refer a patient with chronic hoarseness (symptoms persisting for >6 weeks) of unclear origin. Reflux medication (85.8%) and antihistamines (54.2%) were the most commonly selected choices for empirical treatment. Most physician respondents (79.2%) reported that they would treat chronic hoarseness with reflux medication in a patient without evidence of gastroesophageal reflux disease. CONCLUSIONS AND RELEVANCE: Most PCPs who responded to our survey report empirically treating patients with chronic hoarseness of unknown origin. Many physician respondents were willing to empirically prescribe reflux medication as primary therapy, even when symptoms of gastroesophageal reflux disease were not present. These data suggest that PCPs strongly consider reflux a common cause of dysphonia and may empirically treat patients having dysphonia with reflux medication before referral.


Assuntos
Rouquidão/terapia , Refluxo Laringofaríngeo/terapia , Médicos de Atenção Primária/normas , Padrões de Prática Médica/normas , Inquéritos e Questionários , Rouquidão/diagnóstico , Rouquidão/etiologia , Humanos , Refluxo Laringofaríngeo/complicações , Refluxo Laringofaríngeo/diagnóstico , Estudos Prospectivos , Encaminhamento e Consulta , Estados Unidos
7.
J Dent Educ ; 71(8): 1027-39, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17687085

RESUMO

The issues of cheating and plagiarism in educational settings have received a large amount of attention in recent years. The purpose of this study was to assess the degree to which academic integrity issues currently exist in the dental schools throughout the United States and Canada. An online survey was developed to gather data pertaining to this topic from two key groups in dental education: faculty and students. Responses were obtained from 1,153 students and 423 faculty members. The results of the survey clearly reveal that cheating is a significant problem in dental schools and that significant differences exist between students' and faculty members' perceptions of academic integrity. The challenge for dental schools is to identify effective strategies to prevent cheating opportunities and to implement and enforce effective means of dealing with specific examples of cheating.


Assuntos
Educação em Odontologia/normas , Ética Odontológica , Docentes de Odontologia , Faculdades de Odontologia/normas , Estudantes de Odontologia , Adulto , Canadá , Enganação , Avaliação Educacional , Docentes de Odontologia/estatística & dados numéricos , Feminino , Humanos , Masculino , Plágio , Má Conduta Profissional , Estudantes de Odontologia/psicologia , Estudantes de Odontologia/estatística & dados numéricos , Estados Unidos
8.
Mol Cell Biol ; 23(21): 7849-60, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14560028

RESUMO

Expansion of trinucleotide repeats (TNRs) is the causative mutation in several human genetic diseases. Expanded TNR tracts are both unstable (changing in length) and fragile (displaying an increased propensity to break). We have investigated the relationship between fidelity of lagging-strand replication and both stability and fragility of TNRs. We devised a new yeast artificial chromomosme (YAC)-based assay for chromosome breakage to analyze fragility of CAG/CTG tracts in mutants deficient for proteins involved in lagging-strand replication: Fen1/Rad27, an endo/exonuclease involved in Okazaki fragment maturation, the nuclease/helicase Dna2, RNase HI, DNA ligase, polymerase delta, and primase. We found that deletion of RAD27 caused a large increase in breakage of short and long CAG/CTG tracts, and defects in DNA ligase and primase increased breakage of long tracts. We also found a correlation between mutations that increase CAG/CTG tract breakage and those that increase repeat expansion. These results suggest that processes that generate strand breaks, such as faulty Okazaki fragment processing or DNA repair, are an important source of TNR expansions.


Assuntos
Replicação do DNA , Proteínas Fúngicas/genética , Mutação , Proteínas de Saccharomyces cerevisiae , Expansão das Repetições de Trinucleotídeos , Leveduras/genética , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Bioensaio , Cromossomos Artificiais , Dano ao DNA , DNA Helicases/genética , DNA Helicases/metabolismo , DNA Ligases/genética , DNA Ligases/metabolismo , DNA Polimerase III/genética , DNA Polimerase III/metabolismo , DNA Primase/genética , DNA Primase/metabolismo , Endonucleases Flap/genética , Endonucleases Flap/metabolismo , Proteínas Fúngicas/metabolismo , Humanos , Reprodutibilidade dos Testes , Ribonuclease H/genética , Ribonuclease H/metabolismo , Leveduras/metabolismo
9.
J Dent Educ ; 67(4): 427-38, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12749572

RESUMO

A major trend at all levels of education in recent years has been the advent of distance learning and, more specifically, the use of computers and communications capabilities to provide online learning. The purpose of this study was to determine the extent to which distance learning and online technologies are being employed by dental schools in the United States and Canada. Two groups were surveyed: academic deans and faculty members of U.S. and Canadian dental schools. Thirty-eight academic deans responded to a paper-based survey, and more than 400 faculty members responded to a web-based survey. The results of these surveys indicate that online delivery of content and information has a bright future in the delivery of the dental school curriculum. At the same time, formidable obstacles must be addressed for this approach to be successful.


Assuntos
Currículo , Educação em Odontologia/métodos , Educação a Distância , Pessoal Administrativo , Canadá , Coleta de Dados , Tecnologia Educacional , Docentes de Odontologia , Feminino , Humanos , Internet/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Faculdades de Odontologia , Estados Unidos
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