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1.
Opt Express ; 31(25): 41326-41338, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38087534

RESUMEN

We demonstrate laser frequency stabilization with at least 6 GHz of offset tunability using an in-phase/quadrature (IQ) modulator to generate electronic sidebands (ESB) on a titanium sapphire laser at 714 nm and we apply this technique to perform isotope shift spectroscopy of 226Ra and 225Ra. By locking the laser to a single resonance of a high finesse optical cavity and adjusting the lock offset, we determine the frequency difference between the magneto-optical trap (MOT) transitions in the two isotopes to be 2630.0 ± 0.3 MHz, a factor of 29 more precise than the previously available data. Using the known value of the hyperfine splitting of the 3P1 level, we calculate the isotope shift for the 1S0 to 3P1 transition to be 2267.0 ± 2.2 MHz, a factor of 8 more precise than the best available value. Our technique could be applied to countless other atomic systems to provide unprecedented precision in isotope shift spectroscopy and other relative frequency comparisons.

3.
Rev Sci Instrum ; 94(6)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37862488

RESUMEN

A radium-223 ion beam was delivered to an experiment from the electron cyclotron resonance ion source, ECR2, at the Argonne Tandem Linac Accelerator System (ATLAS). The radium-223 material was in a nitrate salt form within a vial, prior to being converted to a usable sputter sample. The sputter sample was produced using a new sample preparation method, where the radium nitrate was dissolved into a solution and pipetted onto pressed aluminum powder. This sample was then allowed to dry, distributing the radium-223 material throughout the sputter sample. Ion source operation using the radium sputter sample is described with the operating parameters listed. The intensity and energy requirements for this ion beam were 1 × 106 particles/s and 1.07 GeV, respectively. Because the intensity is relatively low compared to most experiments at ATLAS, previously developed accelerator mass spectrometry methods were used Scott et al. [Rev. Sci. Instrum. 87, 02A732 (2016)] to avoid the need for tuning of the low-intensity beam of interest. Handling of the radium material, as well as loading and unloading of the sputter sample from ECR2, required collaboration with Health Physics. Procedures were used and dry runs were carried out before, during, and after the experiment to ensure the safety of the workers. The processes used and lessons learned are described within.

4.
Heliyon ; 9(5): e15903, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37168883

RESUMEN

As global wind energy capacity continues to expand, the need to site commercial wind farms in productive, affordable, and technically feasible locations has become increasingly important. The use of wind farm site suitability models to identify these locations has grown consequently, thus increasing interest in standardizing certain aspects of these models' development. This systematic review of wind farm site suitability studies seeks to identify similarities and differences in the selection and representation of their enlisted siting factors. The review focuses on how subjective modeling decisions, such as vocabulary choices and dataset selection, occur in the literature, based on five identified themes: 1) Deciding Upon Siting Factors, which explains how a study's geographical context, selected modeling approach, and modeler decisions can influence siting factor selection; 2) Classifying Data and Siting Factor Terminology, which addresses the extent and the advantages of consistent siting factor vocabulary; 3) Implementing Siting Factors as Constraints or as Evaluation Criteria, which covers the importance of consistent implementation and of specifying logic when enlisting siting factors to assess potential wind farm sites; 4) Utilizing Primary and Secondary Data, which details how a study's reliance on external or self-collected datasets influences siting factor representation; and 5) Data Source and Accessibility, which highlights the inconsistent provision of citations and dataset sources, and the availability of datasets for siting factors to the broader scientific community. Standardizing the selection and representation of siting factors would benefit comparisons between wind farm site suitability studies and communication of model outputs to a wider audience.

5.
Phys Rev Lett ; 130(19): 192502, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37243659

RESUMEN

We present the first measurement of the α-ß-ν angular correlation in the Gamow-Teller ß^{+} decay of ^{8}B. This was accomplished using the Beta-decay Paul Trap, expanding on our previous work on the ß^{-} decay of ^{8}Li. The ^{8}B result is consistent with the V-A electroweak interaction of the standard model and, on its own, provides a limit on the exotic right-handed tensor current relative to the axial-vector current of |C_{T}/C_{A}|^{2}<0.013 at the 95.5% confidence level. This represents the first high-precision angular correlation measurements in mirror decays and was made possible through the use of an ion trap. By combining this ^{8}B result with our previous ^{8}Li results, we demonstrate a new pathway for increased precision in searches for exotic currents.

7.
J Int Adv Otol ; 19(1): 66-69, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36718040

RESUMEN

Vestibular schwannomas often present with unilateral hearing loss, tinnitus, or dizziness. Imaging is commonly pursued in individuals with unexplained unilateral sensorineural hearing loss, deterioration in word recognition scores, or persistent tinnitus. We present the case of a 76-year-old male with cough-induced vertigo as his primary presenting symptom. Vestibular testing suggested a right vestibular hypofunction, and a small right-sided vestibular schwannoma was discovered using magnetic resonance imaging. Cough-induced vertigo and associated nystagmus may be a presenting feature of vestibular schwannoma.


Asunto(s)
Pérdida Auditiva Sensorineural , Neuroma Acústico , Acúfeno , Masculino , Humanos , Anciano , Neuroma Acústico/complicaciones , Neuroma Acústico/diagnóstico , Acúfeno/etiología , Tos/etiología , Vértigo/diagnóstico , Vértigo/etiología , Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Sensorineural/etiología , Imagen por Resonancia Magnética/métodos
8.
Health Promot Pract ; 24(4): 728-739, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-35414293

RESUMEN

BACKGROUND AND PURPOSE: There is growing interest in expanding healthy eating interventions in the retail setting. The purpose of this study was to evaluate the implementation of a successful 2-for-1 price incentive for fruits and vegetables (F&V), including frozen and canned, that took place in partnership with a large chain grocery retailer in Maine. Intervention Approach. A randomized controlled trial (RCT) pilot study was conducted in 2015-2016, followed by a larger RCT in 2016-2017, to assess whether a supermarket double-dollar F&V incentive increased purchases of these items. EVALUATION METHODS: A convergent, parallel mixed-methods design was used to examine barriers and facilitators to implementing the interventions, using six implementation outcomes: acceptability, adoption, appropriateness, feasibility, implementation fidelity, and perceived cost. RESULTS: The intervention was deemed highly acceptable, appropriate, and feasible by shoppers, retailers, and researchers. The F&V discount had a high rate of initial adoption. There was a moderate degree of fidelity, which improved over time based on lessons learned from the pilot and applied to the subsequent RCT. Specific costs associated with implementation from the research perspective are reported. Implications for Practice, Policy, and Research. Partnerships between academic researchers and retailers can be an effective model for improving healthful purchases among shoppers. These findings are relevant for investigators, public health advocates, and retailers interested in implementing similar grocery retail-based interventions.


Asunto(s)
Frutas , Verduras , Humanos , Motivación , Mercadotecnía , Dieta Saludable , Comercio
12.
J Am Acad Audiol ; 32(1): 35-38, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33873212

RESUMEN

PURPOSE: To investigate the prevalence of reversal nystagmus in individuals with benign paroxysmal positional vertigo (BPPV). STUDY DESIGN: Prevalence of reversal nystagmus was assessed in 28 subjects with unilateral posterior canal BPPV, canalithiasis type. Six trials of Dix-Hallpike testing were completed for each subject. RESULTS: Reversal nystagmus was present in 129 out of 167 Dix-Hallpike maneuvers that were performed (77.2%). In 19 trials where nystagmus was absent with the dependent position of Dix-Hallpike testing, reversal nystagmus was nonetheless demonstrated in 11 trials (57.9%). CONCLUSION: Reversal nystagmus is commonly demonstrated in individuals with posterior canal BPPV, canalithiasis type. It is frequently evoked even when there is no nystagmus with the dependent position of Dix-Hallpike testing. Observation of reversal nystagmus may enhance the identification of BPPV during Dix-Hallpike testing.


Asunto(s)
Vértigo Posicional Paroxístico Benigno , Nistagmo Patológico , Vértigo Posicional Paroxístico Benigno/epidemiología , Ambiente , Humanos , Nistagmo Patológico/diagnóstico , Nistagmo Patológico/epidemiología , Prevalencia , Canales Semicirculares
13.
Pilot Feasibility Stud ; 6: 126, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32944274

RESUMEN

BACKGROUND: Post-transplant weight gain affects 50-90% of kidney transplant recipients adversely affecting survival, quality of life, and risk for diabetes and cardiovascular disease. Diet modification and physical activity may help prevent post-transplant weight gain. Methods for effective implementation of these lifestyle modifications are needed. The objective of this study is to assess the feasibility and acceptability of a remotely delivered nutrition and physical activity intervention among kidney transplant recipients. Secondary aims were to estimate the effectiveness of the intervention in producing changes in physical activity, qualify of life, fruit and vegetable intake, and consumption of whole grains and water from baseline to 6 months. METHODS: A randomized controlled study for stable kidney transplant recipients between 6 and 12 months post-transplantation was conducted. Participants were randomly assigned 1:1 to a technology-based, lifestyle modification program (intervention) or to enhanced usual care (control). RESULTS: The first 10 kidney transplant recipients screened were eligible and randomized into the intervention and control groups with no significant between-group differences at baseline. Health coaching attendance (78%) and adherence to reporting healthy behaviors (86%) were high. All participants returned for final assessments. The weight in controls remained stable, while the intervention arm showed weight gain at 3 and 6 months. Improvements were found for physical activity, quality of life, and fruit and vegetable intake in both groups. All participants would recommend the program to other transplant recipients. CONCLUSIONS: Our data suggest that a remotely delivered televideo nutrition and physical activity intervention is feasible and valued by patients. These findings will aid in the development of a larger, more prescriptive, randomized trial to address weight gain prevention. TRIAL REGISTRATION: Clinicaltrials.gov Identifier NCT03697317. Retrospectively registered on October 5, 2018.

15.
Knee Surg Sports Traumatol Arthrosc ; 28(11): 3676-3685, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32699921

RESUMEN

PURPOSE: To present the results of a return to sports bridge program designed to reduce knee injuries following ACL reconstruction and physical therapy. METHODS: One hundred and fifty (male = 83, female = 67) patients participated in a whole body neuromuscular control, progressive resistance strength and agility training program. Post-program testing included functional movement form, dynamic knee stability, lower extremity power, agility, and sports skill assessments. Participants completed the Knee Outcome Survey-Sports Activity Scale (KOS-SAS) before and after program initiation. Pre-participation scores were re-estimated following program completion. RESULTS: Global rating KOS-SAS score at program entry was 75 ± 13. Post-program global rating and calculated KOS-SAS were 91.0 ± 9.8 and 90.9 ± 9.7, respectively (p < 0.0001). Pre-participation KOS-SAS score re-estimates at program completion were 54.5 ± 23.3 and 57.3 ± 18.5, respectively. The approximately 20% lower pre-program KOS-SAS score re-estimates (p < 0.0001) observed at program completion suggests that subjects had inaccurately high sports readiness perceptions at program entry. Perceived overall sports activity knee function ratings improved from 2.9 ± 0.6 (abnormal) at program entry to 1.3 ± 0.5 (normal) at completion (p < 0.0001). Most subjects returned back to sports at or above their pre-injury performance skill/performance level (84%, 126/150). By 6.8 ± 3.2 years (range = 2-13 years) post-surgery, ten subjects had sustained an ipsilateral knee re-injury or contralateral knee injury (6.7%). The 2.7% non-contact contralateral and 1.3% non-contact ipsilateral knee injury rates observed were significantly lower than those cited in previous reports. CONCLUSION: Supplementing primary ACL reconstruction and standard physical therapy with a return to sports bridge program prior to release to unrestricted sports performance was effective at improving patient outcomes and decreasing ipsilateral knee re-injury and contralateral knee injury rates. LEVEL OF EVIDENCE: II.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior/rehabilitación , Reconstrucción del Ligamento Cruzado Anterior , Rendimiento Atlético , Terapia por Ejercicio/métodos , Volver al Deporte , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior/cirugía , Femenino , Humanos , Rodilla/cirugía , Traumatismos de la Rodilla/prevención & control , Articulación de la Rodilla/cirugía , Masculino , Examen Físico , Estudios Prospectivos , Lesiones de Repetición/prevención & control , Encuestas y Cuestionarios , Adulto Joven
16.
Environ Entomol ; 49(4): 876-885, 2020 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-32623469

RESUMEN

A number of soybean varieties traditionally bred for resistance to various soybean arthropod pests have been identified as resistant to Megacopta cribraria (F.) (Hemiptera: Plataspidae). However, the mechanisms of host-plant resistance (HPR) in this system are not understood. The goal of this study was to identify the mechanisms of resistance by examining the role of plant volatile organic compounds (VOCs) and free amino acids (FAAs) among 16 soybean varieties. Choice and no-choice cage experiments identified several soybean varieties that demonstrated antixenosis as well as antibiosis. However, resistance varied over time in certain soybean varieties, such as N02-7002 and PI567352B. Mean nymph number from choice experiments had positive correlations with the FAAs asparagine, tryptophan, alanine, phenylanaline, and serine; negative correlation with leucine and threonine. Four plant volatiles, hexanal, 2-pentylfuran, beta-cyclocitral, and cis-9-hexadecenal, were positively correlated with subsequent nymph development, whereas n-hexadecenoic acid was negatively correlated with nymph number only, in adult choice cage experiments. This study contributes to understanding the mechanisms of HPR through associations with plant VOCs and FAAs in relation to M. cribraria development and provides useful knowledge for developing soybean varieties for M. cribraria management.


Asunto(s)
Fabaceae , Hemípteros , Heterópteros , Compuestos Orgánicos Volátiles , Animales , Ninfa , Glycine max
17.
Contemp Clin Trials ; 90: 105952, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32006633

RESUMEN

Only 43% of children in the U.S., ages 6-11 yrs., meet current physical activity (PA) guidelines. To satisfy the MVPA requirement, schools have begun incorporating MVPA in the form of activity breaks or MVPA academic lessons. We completed two, 3 academic-yr. cluster randomized trials (DK61489, DK85317) called "Physical Activity Across the Curriculum" (PAAC) which involved increasing MVPA in the classroom. Across 3-yrs. teachers in PAAC schools delivered ~60 min/wk. (12 min/day) of MVPA. Although short of our MVPA goal (20 min/d), the PAAC approach substantially increased in-school MVPA. Teacher reluctance to devote additional time to develop and integrate PA lessons into their curriculum was the overwhelming barrier to meeting the MVPA goal. Therefore, to reduce barriers to delivery of classroom PA we developed a 3-academic yr. cluster randomized trial (2 yrs. active intervention, 1 yr. follow-up) to compare the effectiveness and sustainability of technology delivered (PAAC-R) and classroom teacher delivered (PAAC-T) activity breaks for increasing classroom MVPA in elementary school students in grades 2 and 3 at baseline who will progress to grades 4-5. NCT registration: NCT03493139.


Asunto(s)
Ejercicio Físico , Promoción de la Salud/organización & administración , Instituciones Académicas/organización & administración , Pesos y Medidas Corporales , Capacidad Cardiovascular/fisiología , Niño , Metabolismo Energético/fisiología , Ambiente , Femenino , Humanos , Masculino , Proyectos de Investigación , Características de la Residencia , Maestros/psicología , Factores Socioeconómicos , Formación del Profesorado/organización & administración , Factores de Tiempo , Estados Unidos
18.
Environ Entomol ; 49(1): 88-97, 2020 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-31904078

RESUMEN

Megacopta cribraria (F.) (Hemiptera: Plataspidae) is an invasive pest of soybean that has spread across the southeastern United States since its initial discovery in 2009 in Georgia. Previous studies in the southeastern states have documented both the population dynamics of this pest and host plant resistance (HPR) among soybean varieties, although the specific mechanisms of HPR remain unknown. The objectives of this study were, therefore, to 1) quantify field resistance to M. cribraria in multiple soybean varieties in two states previously affected by severe M. cribraria infestations, North Carolina (NC) and South Carolina (SC); and 2) study the role of soybean trichome density in imparting resistance against M. cribraria. Soybean variety 'Camp' was least attractive to M. cribraria, through time and locations, suggesting consistent resistance. Other varieties showed variable performance among the locations and sampling dates. A significant difference in trichome density was evident. However, there was no correlation between trichome density and M. cribraria infestation. Compared to a previously published study in the same location, when M. cribraria adults emerging from overwintering dispersed into soybeans, in our study only first-generation adults dispersed into soybeans. Considering the current trend of significantly lower M. cribraria infestation rates in North and South Carolina, this pest may be finally succumbing to indigenous natural enemies and should be managed by incorporating integrated pest management tactics, such as HPR, that help conserve natural enemy populations.


Asunto(s)
Glycine max , Heterópteros , Animales , Georgia , North Carolina , Ninfa , South Carolina , Tricomas
19.
Pediatr Ann ; 48(10): e395-e399, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31609998

RESUMEN

Macrophage activation syndrome (MAS) is a potentially life-threatening condition that may complicate many pediatric rheumatologic diseases. Because of its similarity in presentation to other conditions with overlapping manifestations, such as flares of rheumatologic disease or systemic infection, and the fact that there exists no single pathognomonic clinical finding or laboratory parameter to aid in diagnosis, MAS presents a significant diagnostic challenge to the practicing pediatrician with limited access to consulting pediatric rheumatologists. Along with a review of the physiology and manifestations of the condition, we have included the most current consensus for diagnosing MAS. [Pediatr Ann. 2019;48(10):e395-e399.].


Asunto(s)
Síndrome de Activación Macrofágica/diagnóstico , Adolescente , Artritis Juvenil/complicaciones , Femenino , Humanos , Inmunosupresores/uso terapéutico
20.
Contemp Clin Trials ; 84: 105817, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31344519

RESUMEN

Adolescents with intellectual and developmental disabilities (IDD) are less physically active and have lower cardiovascular fitness compared with their typically developing peers. This population faces additional barriers to participation in moderate-to-vigorous physical activity (MVPA) such as reliance on parents, lack of peer-support, and lack of inclusive physical activity opportunities. Previous interventions to increase MVPA in adolescents with IDD have met with limited success, at least in part due to requiring parents to transport their adolescent to an exercise facility. We recently developed a remote system to deliver MVPA to groups of adolescents with IDD in their homes via video conferencing on a tablet computer. This approach eliminates the need for transportation and provides social interaction and support from both a health coach and other participants. We will conduct a 18-mo. trial (6 mos. active, 6 mos. maintenance, 6 mos. no-contact follow-up) to compare changes in objectively assessed MVPA in 114 adolescents with IDD randomized to a single level intervention delivered only to the adolescent (AO) or a multi-level intervention delivered to both the adolescent and a parent (A + P). Our primary aim is to compare increases in MVPA (min/d) between the AO and A + P groups from 0 to 6 mos. Secondarily we will compare changes in MVPA, sedentary time, cardiovascular fitness, muscular strength, motor ability, quality of life, and the percentage of adolescents achieving the US recommendation of 60 min. MVPA/d across 18 mos. We will also explore the influence of process variables/participant characteristics on changes in MVPA across 18 mos. NCT registration: NCT03684512.


Asunto(s)
Discapacidades del Desarrollo/epidemiología , Ejercicio Físico , Promoción de la Salud/métodos , Discapacidad Intelectual/epidemiología , Padres/educación , Adolescente , Niño , Computadoras de Mano , Conocimientos, Actitudes y Práctica en Salud , Estado de Salud , Humanos , Padres/psicología , Calidad de Vida , Autoeficacia , Apoyo Social , Factores de Tiempo , Comunicación por Videoconferencia , Adulto Joven
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