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1.
Acad Psychiatry ; 46(3): 331-337, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34623622

RESUMO

OBJECTIVE: The introduction of the Milestone Project underscored the need for objective assessments of resident progress across the competencies. Therefore, the authors examined the Psychiatry Resident-In-Training Examination (PRITE) utility for measuring improvements in medical knowledge (MK). METHODS: The authors compared the mean performance for each MK subcompetency by resident year for all residents taking the PRITE from 2015 to 2017 (18,175 examination administrations). In addition, they surveyed psychiatry residency program directors regarding how well they thought they teach these subcompetencies. RESULTS: Increases in MK subcompetencies by resident year were significant for Psychopathology (p < 0.003), Psychotherapy (p < 0.002), and Somatic Therapies (p < 0.000). Development, Clinical Neuroscience, and Practice of Psychiatry did not show statistically significant differences between postgraduate years. Eighty psychiatry program directors responded to the survey and felt optimistic about their ability to teach the Psychopathology, Psychotherapy, Somatic Therapies, and Practice of Psychiatry subcompetencies. CONCLUSIONS: The PRITE measured significant improvements in medical knowledge for several of the core subcompetencies. The program director's responses would suggest that the lack of statistically significant differences found for Development and Clinical Neuroscience reflects areas in need of curricular development. The disparity between PRITE performance and program director perception of the Practice of Psychiatry subcompetency may reflect difficulties in defining the scope of this subcompetency. Overall, this suggests that structured examinations help measure improvements in certain subcompetencies and may also help identify curricular needs. However, there may be potential problems with the definition of some subcompetencies.


Assuntos
Internato e Residência , Psiquiatria , Competência Clínica , Educação de Pós-Graduação em Medicina , Avaliação Educacional , Humanos , Psiquiatria/educação
2.
IEEE Trans Electron Devices ; 67(1): 328-334, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32099264

RESUMO

We report the design and experimental demonstration of a frequency tunable terahertz gyrotron at 527 GHz built for an 800 MHz Dynamic Nuclear Polarization enhanced Nuclear Magnetic Resonance (DNP-NMR) spectrometer. The gyrotron is designed at the second harmonic (ω = 2ω c) of the electron cyclotron frequency. It produces up to 9.3 W continuous microwave (CW) power at 527.2 GHz frequency using a diode type electron gun operating at V = 16.65 kV, Ib = 110 mA in a TE11,2,1 mode, corresponding to an efficiency of ~0.5%. The gyrotron is tunable within ~ 0.4 GHz by combining voltage and magnetic field tuning. The gyrotron has an internal mode converter that produces a Gaussian-like beam that couples to the HE11 mode of an internal 12 mm i.d. corrugated waveguide periscope assembly leading up to the output window. An external corrugated waveguide transmission line system is built including a corrugated taper from 12 mm to 16 mm i.d. waveguide followed by 3 m of the 16 mm i.d. waveguide The microwave beam profile is measured using a pyroelectric camera showing ~ 84% HE11 mode content.

3.
J Health Commun ; 25(12): 931-942, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33656415

RESUMO

This study conceptually and empirically distinguishes two mental processes in narrative processing of food safety health messages-identification with and egocentric projection onto story characters. Two studies examined the effects of narrative autobiographical accounts of contracting foodborne illness (salmonella) because of careless food preparation. Both studies consistently found that identification increased, but egocentric projection decreased audience members' behavioral intention to perform safe food handling practices, indicating that egocentric projection and identification represent unique mental processes and yield distinct persuasive outcomes. In addition, confirmatory factor analyses provided evidence that egocentric projection and identification are distinct constructs. Implications for the role of identification and egocentric projection for understanding narrative processing and for health persuasion are discussed.


Assuntos
Doenças Transmitidas por Alimentos , Comunicação em Saúde/métodos , Narração , Comunicação Persuasiva , Adulto , Egocentrismo , Feminino , Humanos , Identificação Psicológica , Masculino
4.
Phys Rev Lett ; 122(1): 014801, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31012710

RESUMO

We present the first demonstration of high-power, reversed-Cherenkov wakefield radiation by electron bunches passing through a metamaterial structure. The structure supports a fundamental transverse magnetic mode with a negative group velocity leading to reversed-Cherenkov radiation, which was clearly verified in the experiments. Single 45 nC electron bunches of 65 MeV traversing the structure generated up to 25 MW in 2 ns pulses at 11.4 GHz, in excellent agreement with theory. Two bunches of 85 nC with appropriate temporal spacing generated up to 80 MW by coherent wakefield superposition, the highest rf power that metamaterial structures ever experienced without damage. These results demonstrate the unique features of metamaterial structures that are very attractive for future high-gradient wakefield accelerators, including two-beam and collinear accelerators. Advantages include the high shunt impedance for high-power generation and high-gradient acceleration, the simple and rugged structure, and a large parameter space for optimization.

5.
Appetite ; 108: 407-415, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27780785

RESUMO

Media's presentation of eating is an important source of influence on viewers' eating goals and behaviors. Drawing on recent research indicating that whether a story character continues to pursue a goal or completes a goal can unconsciously influence an audience member's goals, a scene from a popular movie comedy was manipulated to end with a character continuing to eat (goal ongoing) or completed eating (goal completed). Participants (N = 147) were randomly assigned to a goal status condition. As a reward, after viewing the movie clip viewers were offered two types of snacks: ChexMix and M&M's, in various size portions. Viewers ate more food after watching the characters continue to eat compared to watching the characters complete eating, but only among those manipulated to identify with a character. Viewers were more likely to choose savory food after viewing the ongoing eating scenes, but sweet dessert-like food after viewing the completed eating scenes. The results extend the notion of media influence on unconscious goal contagion and satiation to movie eating, and raise the possibility that completing a goal can activate a logically subsequent goal. Implications for understanding media influence on eating and other health behaviors are discussed.


Assuntos
Ingestão de Alimentos/psicologia , Comportamento Alimentar/psicologia , Comportamentos Relacionados com a Saúde , Filmes Cinematográficos , Adolescente , Comportamento de Escolha , Feminino , Preferências Alimentares/psicologia , Humanos , Masculino , Saciação , Lanches , Inquéritos e Questionários , Adulto Jovem
6.
Health Commun ; 32(10): 1297-1309, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27690636

RESUMO

This study explores the effects of habitual health risk behaviors and self-activation on resistance to narrative persuasion. In two experiments, heavier drinkers were more resistant to an anti-binge-drinking narrative public service announcement (PSA) in which a binge drinker suffers a negative outcome. Specifically, heavier drinkers were more likely to generate counterarguments, unrealism judgments, and negative evaluations about the message compared to lighter drinkers or nondrinkers. However, activating self-concept when processing the persuasive narrative reduced unrealism judgments and negative evaluations, particularly among heavier drinkers. Self-activation also decreased perceived freedom threat among both heavier and lighter drinkers, which further led to higher perceived risk of binge drinking. Theoretical and practical implications are discussed.


Assuntos
Comportamento Aditivo , Consumo Excessivo de Bebidas Alcoólicas/prevenção & controle , Narração , Comunicação Persuasiva , Autoimagem , Adulto , Consumo Excessivo de Bebidas Alcoólicas/psicologia , Feminino , Humanos , Masculino , Inquéritos e Questionários
7.
Artigo em Inglês | MEDLINE | ID: mdl-29033474

RESUMO

The design and experimental results of a 140 GHz gyro-amplifier that uses a dielectric-loaded, sever-less confocal waveguide are presented. The gyro-traveling wave amplifier uses the HE06 mode of a confocal geometry with power coupled in and out of the structure with Vlasov-type, quasi-optical couplers. Dielectric loading attached to the side of the confocal structure suppresses unwanted modes allowing zero-drive stable operation at 48 kV and 3A of beam current. The confocal gyro-amplifier demonstrated a peak circuit gain of 35 dB, a bandwidth of 1.2 GHz and a peak output power of 550 W at 140.0 GHz.

8.
Artigo em Inglês | MEDLINE | ID: mdl-28890582

RESUMO

The linear and nonlinear theory of a gyroamplifier using a confocal waveguide is presented. A quasi-optical approach to describing the modes of a confocal waveguide is derived. Both the equations of motion and the mode excitation equation are derived in detail. The confocal waveguide circuit has the advantage of reducing mode competition but the lack of azimuthal symmetry presents challenges in calculating the gain. In the linear regime, the gain calculated using the exact form factor for the confocal waveguide agrees with an azimuthally averaged form factor. A beamlet code including velocity spread effects has been written to calculate the linear and nonlinear (saturated) gain. It has been successfully benchmarked against the MAGY code for azimuthally symmetric cases. For the confocal waveguide, the beamlet code shows that the saturated gain is reduced when compared with results obtained using an azimuthally averaged form factor. The beamlet code derived here extends the capabilities of nonlinear gyroamplifier theory to configurations that lack azimuthal symmetry.

9.
J Health Commun ; 21(12): 1227-1235, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27858526

RESUMO

This study examines when and how shared risk-relevant experience (autobiographic similarity) influences resistance to negatively framed health narratives. We conducted a 2 (narrative perspective: 1st vs. 3rd person) × 2 (processing motive: experiential vs. analytical) randomized experiment with a short narrative depicting the negative effects of an illicitly used study drug. For those autobiographically similar to the study drug user, a 1st-person narration (vs. 3rd-person) produced greater transportation only when participants processed to understand the story (experiential condition), whereas the reverse was found when participants processed for the persuasive message (analytical condition). Transportation was a significant mediator that transferred these interactive effects onto greater perceived risk only among those with autobiographic similarity. This study highlights the active role played by the audience's self-concept in narrative persuasion and addresses boundary conditions for overcoming defensive resistance.


Assuntos
Comunicação em Saúde/métodos , Narração , Autoimagem , Adolescente , Adulto , Mecanismos de Defesa , Feminino , Humanos , Masculino , Comunicação Persuasiva , Assunção de Riscos , Adulto Jovem
11.
Risk Anal ; 35(8): 1423-36, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25809457

RESUMO

Narrative messages are increasingly popular in health and risk campaigns, yet gain/loss framing effects have never been tested with such messages. Three experiments examined framing in narrative messages. Experiment 1 found that only the character's decision, not framing, influenced judgments about characters in a narrative derived from a prospect theory context. Experiment 2 found that a framing effect that occurred when presented in a decision format did not occur when the same situation was presented as a narrative. Using a different story/decision context, Experiment 3 found no significant difference in preference for surgery over radiation therapy in a narrative presentation compared to a non-narrative presentation. The results suggest that health and risk campaigns cannot assume that framing effects will be the same in narrative messages and non-narrative messages. Potential reasons for these differences and suggestions for future research are discussed.


Assuntos
Narração , Comunicação Persuasiva , Assunção de Riscos , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
13.
Health Commun ; 29(8): 791-801, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24228700

RESUMO

Health communication researchers have become increasingly interested in factors that predict support for health-related policy. Previous studies have shown that judgments about issues that are influenced by political ideology can be modified by the depth with which receivers process messages related to that issue. In this study, we test whether the same pattern is found for causal attributions about obesity and, ultimately, support for policies to reduce obesity. A national, random sample of U.S. adults read a story about both individual and societal causes of obesity. The longer the time participants spent on the study, and the more words they generated in a thought-listing procedure (operationalizations of depth of processing), the more likely participants were to support policies to reduce obesity, a traditionally liberal position. The same measures of depth of processing did not influence causal explanation of obesity overall, but the more time political moderates spent on the study, the more likely they were to both attribute societal explanations for obesity's causes and to support policies to combat obesity. We conclude with a discussion of this study's application to health communication campaigns and future research directions.

14.
Health Commun ; 29(5): 431-44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23829316

RESUMO

Narrative messages have the potential to convey causal attribution information about complex social issues. This study examined attributions about obesity, an issue characterized by interrelated biological, behavioral, and environmental causes. Participants were randomly assigned to read one of three narratives emphasizing societal causes and solutions for obesity or an unrelated story that served as the control condition. The three narratives varied in the extent to which the character in the story acknowledged personal responsibility (high, moderate, and none) for controlling her weight. Stories that featured no acknowledgment and moderate acknowledgment of personal responsibility, while emphasizing environmental causes and solutions, were successful at increasing societal cause attributions about obesity and, among conservatives, increasing support for obesity-related policies relative to the control group. The extent to which respondents were able to make connections between individual and environmental causes of obesity (complex integration) mediated the relationship between the moderate acknowledgment condition and societal cause attributions. We conclude with a discussion of the implications of this work for narrative persuasion theory and health communication campaigns.


Assuntos
Política de Saúde , Obesidade/psicologia , Comunicação Persuasiva , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Causalidade , Empatia , Meio Ambiente , Feminino , Comunicação em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/etiologia , Psicologia , Adulto Jovem
15.
Artigo em Inglês | MEDLINE | ID: mdl-25067859

RESUMO

When using overmoded corrugated waveguide transmission lines for high power applications, it is necessary to control the mode content of the system. Ideally, overmoded corrugated transmission lines operate in the fundamental HE11 mode and provide low losses for long distances. Unwanted higher order modes (HOMs), particularly LP11 and HE12, are often excited in the experimental systems due to practical misalignments in the transmission line system. This paper discusses how the unwanted modes propagate along with the fundamental mode in the transmission line system by formulating an equation that relates the center of power offset and angle of propagation of a beam (for the HE11 and LP11 modes) or the waist size and phase front radius of curvature of a beam (for the HE11 and HE12 modes). By introducing two miter bend correctors into the transmission system-miter bends that have slightly angled or ellipsoidal mirrors-the HOMs can be precisely manipulated in the system. This technique can be used to eliminate small quantities of unwanted modes, thereby creating a nearly pure fundamental mode beam with minimal losses. Examples of these applications are calculated and show the theoretical conversion of up to 10% HOM content into the fundamental HE11 mode with minimal losses.

16.
IEEE Trans Plasma Sci IEEE Nucl Plasma Sci Soc ; 42(10): 3358-3364, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25821260

RESUMO

We present a novel, relatively simple method for determining the mode content of the linearly polarized modes of a corrugated waveguide using the moments of the intensity pattern of the field radiated from the end of the waveguide. This irradiance moment method is based on calculating the low-order irradiance moments, using measured intensity profiles only, of the radiated field from the waveguide aperture. Unlike the phase retrieval method, this method does not use or determine the phase distribution at the waveguide aperture. The new method was benchmarked numerically by comparison with sample mode mixtures. The results predict less than ±0.7% error bar in the retrieval of the mode content. The method was also tested using high-resolution experimental data from beams radiated from 63.5 mm and 19 mm corrugated waveguides at 170 and 250 GHz, respectively. The results showed a very good agreement of the mode content retrieved using the irradiance moment method versus the phase retrieval technique. The irradiance moment method is most suitable for cases where the modal power is primarily in the fundamental HE11 mode, with <8% of the power in high-order modes.

17.
Psychodyn Psychiatry ; 52(2): 189-205, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829226

RESUMO

In the fall of 2019, a much-publicized court case brought to national attention the issues of patient-doctor confidentiality when it comes to reporting the deaths of newborns in the United States. It is unclear whether the recent overturning of Roe v. Wade will lead to more cases like this. This article discusses issues of countertransference, as well as the ethical and legal implications were it to be a psychiatrist, in active treatment of such a patient, who would be required to make such a report. More specifically, as in the publicized court case, the patient could be a minor at the time, receiving treatment from a child psychiatrist. The implications of such a case include how countertransference affects the perception of fatal child neglect compared to intentional neonaticide; the ethical dilemma of generating a mandated report with the goal of child safety when such a report could lead to real legal consequences for a minor child; and considerations regarding continued treatment of a patient after such a report is made. It is likely that countertransference, shaped by attitudes toward mothers and idealized views on mothering, may play a large role in all these circumstances.


Assuntos
Maus-Tratos Infantis , Contratransferência , Notificação de Abuso , Humanos , Maus-Tratos Infantis/legislação & jurisprudência , Maus-Tratos Infantis/ética , Notificação de Abuso/ética , Estados Unidos , Recém-Nascido , Criança , Feminino
18.
J Magn Reson ; 364: 107722, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38943993

RESUMO

We present 3D electromagnetic simulations of the coupling of a 250 GHz beam to the sample in a 380 MHz DNP NMR spectrometer. To obtain accurate results for magic angle spinning (MAS) geometries, we first measured the complex dielectric constants of zirconia, sapphire, and the sample matrix material (DNP juice) from room temperature down to cryogenic temperatures and from 220 to 325 GHz with a VNA and up to 1 THz with a THz TDS system. Simulations of the coupling to the sample were carried out with the ANSYS HFSS code as a function of the rotor wall material (zirconia or sapphire), the rotor wall thickness, and the THz beam focusing (lens or no lens). For a zirconia rotor, the B1 field in the sample was found to be strongly dependent on the rotor wall thickness, which is attributed to the high refractive index of zirconia. The optimum thickness of the wall is likely due to a transmission maximum but is offset from the thickness predicted by a simple calculation for a flat slab of the wall material. The B1 value was found to be larger for a sapphire rotor than for a zirconia rotor for all cases studied. The results found in this work provide new insights into the coupling of THz radiation to the sample and should lead to improved designs of future DNP NMR instrumentation.

19.
Prev Chronic Dis ; 10: E209, 2013 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-24331282

RESUMO

INTRODUCTION: Reducing rates of obesity will require interventions that influence both individual decisions and environmental factors through changes in public policy. Previous work indicates that messages emphasizing environmental determinants increases support for public policies, but some suspect this strategy may undermine motivation to engage in diet and exercise. METHODS: Study 1 involved 485 adults recruited from a shopping mall in New York. Study 2 involved 718 adult members of a Web-based national panel of US adults. Respondents in both studies were randomly assigned to read a story that emphasized environmental determinants of health or a control condition. The stories varied in the extent to which they described the story character as taking personal responsibility for weight management. Logistic regression and ordered logit models were used to test for differences in intentions to engage in diet and exercise behaviors based on which story the participant read. Analyses were also performed separately by participants' weight status. RESULTS: In both studies, messages that acknowledged personal responsibility while emphasizing environmental causes of obesity increased intentions to engage in healthy behavior for at least 1 weight status group. CONCLUSION: Emphasizing factors outside of personal control appears to enhance rather than undermine motivations to engage in healthy diet and exercise behavior.


Assuntos
Dieta/psicologia , Exercício Físico/psicologia , Intenção , Obesidade/etiologia , Meio Social , Adulto , Comércio , Feminino , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Humanos , Internet , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Motivação , New York , Obesidade/epidemiologia , Obesidade/prevenção & controle , Determinantes Sociais da Saúde , Estados Unidos
20.
IEEE Trans Terahertz Sci Technol ; 13(4): 354-361, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37409025

RESUMO

The reflectance (R) and transmittance (T) of Si and GaAs wafers irradiated by a 6 ns pulsed, 532 nm laser have been studied for s- and p-polarized 250 GHz radiation as a function of laser fluence and time. The measurements were carried out using precision timing of the R and T signals, allowing an accurate determination of the absorptance (A) where A=1-R-T. Both wafers had a maximum reflectance above 90% for a laser fluence ≥8 mJ/cm2. Both also showed an absorptance peak of ~50% lasting ~2 ns during the risetime of the laser pulse. Experimental results were compared with a stratified medium theory using the Vogel model for the carrier lifetime and the Drude model for permittivity. Modeling showed that the large absorptance at the early part of the rise of the laser pulse was due to the creation of a lossy, low carrier density layer. For Si, the measured R, T and A were in very good agreement with theory on both the nanosecond time scale and the microsecond scale. For GaAs, the agreement was very good on the nanosecond scale but only qualitatively correct on the microsecond scale. These results may be useful for planning applications of laser driven semiconductor switches.

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