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1.
Phys Rev Lett ; 133(13): 137001, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39392999

RESUMO

Piezoelectric and ferroelectric technologies are currently dominated by perovskite-based ceramics, not only due to their impressive figures of merit, but due to their versatility in size and shape. This allows the dimensions of, for example, lead zirconium titanate and potassium sodium niobate, to be tailored to the needs of thousands of applications across the automotive, medical device, and consumer electronics industries. In this Letter, we significantly advance the performance and customization of biomolecular crystal (nontoxic, biocompatible amino acids, viz., trans-4-hydroxy-L-proline, L-alanine, hydrates of L-arginine and L-asparagine, and γ-glycine) assemblies by growing them as molded, substrate-free piezoelectric elements. This methodology allows for electromechanical properties to be embedded in these assemblies by fine-tuning the chemistry of the biomolecules and thus the functional properties of the single crystal space group. Here, we report the piezoelectric, mechanical, thermal, and structural properties of these amino acid-based polycrystalline actuators. This versatile, low-cost, low-temperature growth method opens up the path to phase in biomolecular piezoelectrics as high-performance, eco-friendly alternatives to ceramics.


Assuntos
Aminoácidos , Aminoácidos/química , Zircônio/química , Titânio/química , Cristalização , Óxidos/química
2.
Clin J Oncol Nurs ; 26(3): 275-282, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35604740

RESUMO

BACKGROUND: Nurse-led education can improve patient satisfaction, and telemedicine has increased patient access during the COVID-19 pandemic. OBJECTIVES: The aim of this article was to investigate how nursing telemedicine educational visits influence patient satisfaction. METHODS: Patients receiving standard of care in-person education for breast cancer radiation therapy (RT) between January 2019 and June 2019 comprised the preintervention cohort. After July 2019, patients received the same information virtually and represented the postintervention cohort. Press Ganey surveys were used to evaluate patient satisfaction, t tests were performed to differentiate satisfaction scores, and f tests were calculated to determine differences in the variances of response. FINDINGS: Patient satisfaction increased in the postintervention cohort for what to expect during RT, how to manage side effects, and nurses' attentiveness to patient questions and worries. There was decreased variance in patient satisfaction in the postintervention group for quality of care received from nurses and caring manner of nurses.


Assuntos
COVID-19 , Telemedicina , Humanos , Pandemias , Satisfação do Paciente , Satisfação Pessoal
3.
Biol Psychol ; 132: 228-232, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29309826

RESUMO

Posttraumatic stress disorder (PTSD) is a major psychiatric disorder that is prevalent in combat veterans. Previous neuroimaging studies have found elevated amygdala activity in PTSD in response to threatening stimuli, but previous work has lacked the temporal specificity to study fast bottom-up fear responses involving the amygdala. Forty-four combat veterans, 28 with PTSD and 16 without, completed psychological testing and then a face-processing task during magnetoencephalography (MEG). The resulting MEG data were pre-processed, transformed into the time-frequency domain, and then imaged using a beamforming approach. We found that veterans with PTSD exhibited significantly stronger oscillatory activity from 50 to 450 ms in the left amygdala compared to veterans without PTSD while processing threatening faces. This group difference was not present while viewing neutral faces. The current study shows that amygdala hyperactivity in response to threatening cues begins quickly in PTSD, which makes theoretical sense as an adaptive bottom-up fear response.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Reconhecimento Facial/fisiologia , Magnetoencefalografia/métodos , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Veteranos/psicologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Sinais (Psicologia) , Humanos , Masculino , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia
4.
Psychiatry Res Neuroimaging ; 271: 135-141, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29174765

RESUMO

Recent research indicates the relative benefits of computerized attention control treatment (ACT) and attention bias modification treatment (ABMT) for posttraumatic stress disorder (PTSD); however, neural changes underlying these therapeutic effects remain unknown. This study examines how these two types of attention training modulate neurological dysfunction in veterans with PTSD. A community sample of 46 combat veterans with PTSD participated in a randomized double-blinded clinical trial of ACT versus ABMT and 32 of those veterans also agreed to undergo resting-state magnetoencephalography (MEG) recordings. Twenty-four veterans completed psychological and MEG assessments at pre- and post-training to evaluate treatment effects. MEG data were imaged using an advanced Bayesian reconstruction method and examined using statistical parametric mapping. In this report, we focus on the neural correlates and the differential treatment effects observed using MEG; the results of the full clinical trial have been described elsewhere. Our results indicated that ACT modulated occipital and ABMT modulated medial temporal activity more strongly than the comparative treatment. PTSD symptoms decreased significantly from pre- to post-test. These initial neurophysiological outcome data suggest that ACT modulates visual pathways, while ABMT modulates threat-processing regions, but that both are associated with normalizing aberrant neural activity in veterans with PTSD.


Assuntos
Viés de Atenção/fisiologia , Distúrbios de Guerra/diagnóstico por imagem , Distúrbios de Guerra/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia , Veteranos/psicologia , Adulto , Teorema de Bayes , Distúrbios de Guerra/terapia , Método Duplo-Cego , Humanos , Magnetoencefalografia/métodos , Masculino , Malformações do Sistema Nervoso/fisiopatologia , Malformações do Sistema Nervoso/psicologia , Malformações do Sistema Nervoso/terapia , Descanso/fisiologia , Transtornos de Estresse Pós-Traumáticos/terapia
5.
Front Hum Neurosci ; 11: 205, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28487642

RESUMO

Posttraumatic stress disorder (PTSD) is a debilitating psychiatric condition that is common in veterans returning from combat operations. While the symptoms of PTSD have been extensively characterized, the neural mechanisms that underlie PTSD are only vaguely understood. In this study, we examined the neurophysiology of PTSD using magnetoencephalography (MEG) in a sample of veterans with and without PTSD. Our primary hypothesis was that veterans with PTSD would exhibit aberrant activity across multiple brain networks, especially those involving medial temporal and frontal regions. To this end, we examined a total of 51 USA combat veterans with a battery of clinical interviews and tests. Thirty-one of the combat veterans met diagnostic criteria for PTSD and the remaining 20 did not have PTSD. All participants then underwent high-density MEG during an eyes-closed resting-state task, and the resulting data were analyzed using a Bayesian image reconstruction method. Our results indicated that veterans with PTSD had significantly stronger neural activity in prefrontal, sensorimotor and temporal areas compared to those without PTSD. Veterans with PTSD also exhibited significantly stronger activity in the bilateral amygdalae, parahippocampal and hippocampal regions. Conversely, healthy veterans had stronger neural activity in the bilateral occipital cortices relative to veterans with PTSD. In conclusion, these data suggest that veterans with PTSD exhibit aberrant neural activation in multiple cortical areas, as well as medial temporal structures implicated in affective processing.

6.
Cogn Affect Behav Neurosci ; 16(6): 1140-1149, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27722837

RESUMO

Posttraumatic stress disorder (PTSD) is associated with executive functioning deficits, including disruptions in working memory (WM). Recent studies suggest that attention training reduces PTSD symptomatology, but the underlying neural mechanisms are unknown. We used high-density magnetoencephalography (MEG) to evaluate whether attention training modulates brain regions serving WM processing in PTSD. Fourteen veterans with PTSD completed a WM task during a 306-sensor MEG recording before and after 8 sessions of attention training treatment. A matched comparison sample of 12 combat-exposed veterans without PTSD completed the same WM task during a single MEG session. To identify the spatiotemporal dynamics, each group's data were transformed into the time-frequency domain, and significant oscillatory brain responses were imaged using a beamforming approach. All participants exhibited activity in left hemispheric language areas consistent with a verbal WM task. Additionally, veterans with PTSD and combat-exposed healthy controls each exhibited oscillatory responses in right hemispheric homologue regions (e.g., right Broca's area); however, these responses were in opposite directions. Group differences in oscillatory activity emerged in the theta band (4-8 Hz) during encoding and in the alpha band (9-12 Hz) during maintenance and were significant in right prefrontal and right supramarginal and inferior parietal regions. Importantly, following attention training, these significant group differences were reduced or eliminated. This study provides initial evidence that attention training improves aberrant neural activity in brain networks serving WM processing.


Assuntos
Atenção/fisiologia , Encéfalo/fisiopatologia , Memória de Curto Prazo/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/terapia , Veteranos/psicologia , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Função Executiva/fisiologia , Reconhecimento Facial/fisiologia , Humanos , Imageamento por Ressonância Magnética , Magnetoencefalografia , Masculino , Testes Neuropsicológicos , Prática Psicológica , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/etiologia , Resultado do Tratamento , Exposição à Guerra/efeitos adversos
7.
J Psychiatry Neurosci ; 41(4): 251-60, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26645740

RESUMO

BACKGROUND: Posttraumatic stress disorder (PTSD) is associated with executive functioning deficits, including disruptions in working memory. In this study, we examined the neural dynamics of working memory processing in veterans with PTSD and a matched healthy control sample using magnetoencephalography (MEG). METHODS: Our sample of recent combat veterans with PTSD and demographically matched participants without PTSD completed a working memory task during a 306-sensor MEG recording. The MEG data were preprocessed and transformed into the time-frequency domain. Significant oscillatory brain responses were imaged using a beamforming approach to identify spatiotemporal dynamics. RESULTS: Fifty-one men were included in our analyses: 27 combat veterans with PTSD and 24 controls. Across all participants, a dynamic wave of neural activity spread from posterior visual cortices to left frontotemporal regions during encoding, consistent with a verbal working memory task, and was sustained throughout maintenance. Differences related to PTSD emerged during early encoding, with patients exhibiting stronger α oscillatory responses than controls in the right inferior frontal gyrus (IFG). Differences spread to the right supramarginal and temporal cortices during later encoding where, along with the right IFG, they persisted throughout the maintenance period. LIMITATIONS: This study focused on men with combat-related PTSD using a verbal working memory task. Future studies should evaluate women and the impact of various traumatic experiences using diverse tasks. CONCLUSION: Posttraumatic stress disorder is associated with neurophysiological abnormalities during working memory encoding and maintenance. Veterans with PTSD engaged a bilateral network, including the inferior prefrontal cortices and supramarginal gyri. Right hemispheric neural activity likely reflects compensatory processing, as veterans with PTSD work to maintain accurate performance despite known cognitive deficits associated with the disorder.


Assuntos
Encefalopatias/fisiopatologia , Memória de Curto Prazo/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Córtex Cerebral/fisiologia , Distúrbios de Guerra/fisiopatologia , Distúrbios de Guerra/psicologia , Função Executiva/fisiologia , Humanos , Magnetoencefalografia , Masculino , Testes Neuropsicológicos , Transtornos de Estresse Pós-Traumáticos/psicologia , Veteranos , Saúde dos Veteranos
8.
Am J Psychiatry ; 172(12): 1233-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26206075

RESUMO

OBJECTIVE: Attention allocation to threat is perturbed in patients with posttraumatic stress disorder (PTSD), with some studies indicating excess attention to threat and others indicating fluctuations between threat vigilance and threat avoidance. The authors tested the efficacy of two alternative computerized protocols, attention bias modification and attention control training, for rectifying threat attendance patterns and reducing PTSD symptoms. METHOD: Two randomized controlled trials compared the efficacy of attention bias modification and attention control training for PTSD: one in Israel Defense Forces veterans and one in U.S. military veterans. Both utilized variants of the dot-probe task, with attention bias modification designed to shift attention away from threat and attention control training balancing attention allocation between threat and neutral stimuli. PTSD symptoms, attention bias, and attention bias variability were measured before and after treatment. RESULTS: Both studies indicated significant symptom improvement after treatment, favoring attention control training. Additionally, both studies found that attention control training, but not attention bias modification, significantly reduced attention bias variability. Finally, a combined analysis of the two samples suggested that reductions in attention bias variability partially mediated improvement in PTSD symptoms. CONCLUSIONS: Attention control training may address aberrant fluctuations in attention allocation in PTSD, thereby reducing PTSD symptoms. Further study of treatment efficacy and its underlying neurocognitive mechanisms is warranted.


Assuntos
Atenção/fisiologia , Terapia Comportamental/métodos , Transtornos de Estresse Pós-Traumáticos/terapia , Veteranos/psicologia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Estresse Pós-Traumáticos/psicologia , Resultado do Tratamento , Adulto Jovem
9.
Psychiatry Res ; 233(2): 194-200, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-26184460

RESUMO

Posttraumatic stress disorder (PTSD) is a severe psychiatric disorder prevalent in combat veterans. Previous neuroimaging studies have demonstrated that patients with PTSD exhibit abnormal responses to non-threatening visual and auditory stimuli, but have not examined somatosensory processing. Thirty male combat veterans, 16 with PTSD and 14 without, completed a tactile stimulation task during a 306-sensor magnetoencephalography (MEG) recording. Significant oscillatory neural responses were imaged using a beamforming approach. Participants also completed clinical assessments of PTSD, combat exposure, and depression. We found that veterans with PTSD exhibited significantly reduced activity during early (0-125 ms) tactile processing compared with combat controls. Specifically, veterans with PTSD had weaker activity in the left postcentral gyrus, left superior parietal area, and right prefrontal cortex in response to nonthreatening tactile stimulation relative to veterans without PTSD. The magnitude of activity in these brain regions was inversely correlated with symptom severity, indicating that those with the most severe PTSD had the most abnormal neural responses. Our findings are consistent with a resource allocation view of perceptual processing in PTSD, which directs attention away from nonthreatening sensory information.


Assuntos
Nível de Alerta/fisiologia , Magnetoencefalografia , Lobo Parietal/fisiopatologia , Córtex Sensório-Motor/fisiopatologia , Limiar Sensorial/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Tato/fisiologia , Veteranos/psicologia , Adulto , Campanha Afegã de 2001- , Atenção/fisiologia , Mapeamento Encefálico , Humanos , Guerra do Iraque 2003-2011 , Masculino , Valores de Referência , Estatística como Assunto
10.
Md Med ; 9(4): 26-7, 30, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19186594

RESUMO

Homelessness increases a person's exposure to infectious and communicable diseases. The barriers to treatment as described above are many for the physicians and other providers of health care to this population. Health Care for the Homeless would greatly welcome the help of medical subspecialists in the areas of infectious disease, dermatology, gastroenterology, and pulmonology for some of our particularly challenging patients. We look forward to continuing our collaborations with the medical community in Baltimore City as we serve its most vulnerable citizens.


Assuntos
Doenças Transmissíveis/epidemiologia , Nível de Saúde , Pessoas Mal Alojadas/estatística & dados numéricos , Baltimore/epidemiologia , Hepatite C/epidemiologia , Humanos , Infestações por Piolhos/epidemiologia , Staphylococcus aureus Resistente à Meticilina , Infecções Respiratórias/epidemiologia , Escabiose/epidemiologia , Infecções Cutâneas Estafilocócicas/epidemiologia , Infecções Cutâneas Estafilocócicas/microbiologia
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