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1. Chronic Disease Self-Management of Post-Acute Sequelae of COVID-19 Among Older Adults: A Mixed-Methods Analysis

Author

Thomas-Purcell K, Davenport R, Ayala V, Purcell D, and Ownby RL

Subjects
post-acute sequelae of sars-cov-2 infection, covid-19, long covid, sars-cov-2 cognitive issues, health-related quality of life, self-report questionnaires, qualitative analysis, Geriatrics, RC952-954.6
Abstract

Kamilah Thomas-Purcell,1,* Rosemary Davenport,2,* Victoria Ayala,2,* Donrie Purcell,3,* Raymond L Ownby2,* 1Department of Health Science, Nova Southeastern University, Ft. Lauderdale, FL, USA; 2Department of Psychiatry, Nova Southeastern University, Ft. Lauderdale, FL, USA; 3Satcher Health Leadership Institute, Morehouse School of Medicine, Atlanta, GA, USA*These authors contributed equally to this workCorrespondence: Raymond L Ownby, Nova Southeastern University, Center for Collaborative Research Suite 430, 3301 College Avenue, Ft. Lauderdale, FL, 33314, USA, Tel +1-954-608-4846, Email ro71@nova.eduIntroduction: Approximately 20– 30% of individuals who contract acute coronavirus disease (COVID-19) infection develop longer term complications of their initial infection, referred to as Post-Acute Sequelae of SARS-CoV-2 infection (PASC). PASC is characterized by chronic, varying symptomatology.Methods: Using a mixed methods study design, we aimed to gain insight into individuals’ experience with PASC, including cognitive issues, fatigue, and sleep disturbances. We explored whether our previously developed application (app), aimed at improving self-management skills among individuals with chronic diseases, is relevant for individuals with PASC and gained information to adapt the app for individuals with PASC. The study included 19 individuals, aged 40 years and older, recruited from our research participant database, Nova Southeastern University clinics, and community locations. We included this age range because older adults are more likely to have comorbid conditions, allowing us to better understand the impact of COVID-19 infection in these individuals. Participants completed seven standardized self-report questionnaires online, and an individual semi-structured interview via videoconferencing. Quantitative data were assessed using descriptive statistics and calculating individuals’ scores in relation to norms. Qualitative data were analyzed using a thematic analysis approach. Triangulation of the data was accomplished by calculating correlations between participants’ responses on self-report scales and themes found in semi-structured interviews.Results: Themes included disruption of everyday life, diverse physical symptoms, and cognitive problems including brain fog, fatigue, coping, and emotional upset. Quantitative analysis demonstrated that participants experienced high levels of fatigue, negative mood, cognitive problems, and overall reduction in health-related quality of life (HRQOL). Correlation analyses revealed that individual interview responses were related to participants’ self-report of symptoms on standard questionnaires.Discussion: Findings indicate that self-report questionnaires may reflect the experience of individuals with PASC and its impact. Additionally, further efforts to expand our prior mobile app are warranted among individuals with PASC.Keywords: post-acute sequelae of SARS-CoV-2 infection, COVID-19, long COVID, SARS-CoV-2 cognitive issues, health-related quality of life, self-report questionnaires, qualitative analysis

Published
2023

2. Breakdown of the static picture of defect energetics in halide perovskites: the case of the Br vacancy in CsPbBr3

Author

Cohen, Ayala V., Egger, David A., Rappe, Andrew M., and Kronik, Leeor

Subjects
Condensed Matter - Materials Science
Abstract

We consider the Br vacancy in CsPbBr3 as a prototype for the impact of structural dynamics on defect energetics in halide perovskites (HaPs). Using first-principles molecular dynamics based on density functional theory, we find that the static picture of defect energetics breaks down; the energy of the Br vacancy level is found to be intrinsically dynamic, oscillating by as much as 1 eV on the ps time scale at room temperature. These significant energy fluctuations are correlated with the distance between the neighboring Pb atoms across the vacancy and with the electrostatic potential at these Pb atomic sites. We expect this unusually strong coupling of structural dynamics and defect energetics to bear important implications for both experimental and theoretical analysis of defect characteristics in HaPs. It may also hold significant ramifications for carrier transport and defect tolerance in this class of photovoltaic materials., Comment: 5 figures, 1 table

Published
2018

6. Evaluación de la soya integral cocida y de harina de yuca en la alimentación de aves de postura

Author

Santos V. Eduardo, López G. Arnobio, Ayala V. Juan C., and Hennessey M. Sonia

Subjects
soya integral, harina de yuca, aves de postura, Agriculture
Abstract

Se localizaron poblaciones de la planta en los municipios de Santa Rosa-Cauca y de Mocoa-Putumayo y se hicieron observaciones fenológicas discontinuas entre abril de 1984 y agosto de 1986; simultáneamente se realizaron ensayos de propagación sexual y asexual (estacas y acodos). La floración, fructificación y emisión de follaje se presentaron con cierta periodicidad durante el período de observaciones, en tanto que la caída de follaje no ocurrió en volúmenes apreciables. Los ensayos de propagación sexual fracasaron, mientras que el enraizamiento de estacas, aún utilizando enraizadores, fue muy bajo (6.5 %); las únicas estacas que enraizaron fueron las terminales sembradas con yema foliar y hojas apicales. Todos los acodos formaron callo pero enraizaron más los tratados con enraizadores (75 %).This paper presents phenological, sexual and asexual propagation observations of Elaeagia pastoensis Mora, furthermore some botanic and ecology aspects of the plant were conssidered. The plant was found growing in Santa Rosa-Cauca and Mocoa-Putumayo municipalities where discontinual phenological observations were made; sexual and asexual (stem cutting and aereal layer) propagation experiments were made too. The field work carried out through april 1984 and august1986. Flowering, fruiting and leaf flushing appeared with some regularity during the observations period; the leaf fall was not observed in siqnificant quantyties. The sexual propagations was not sucesfully. The percentage of root setting taken from terminal of the branch with resinal bud leaves and apical leaves set roots. AII aerel layer formed callus, however the hi- ghest percentage of root setting (75%) was reached with treated ones with hormones.

Published
1987

9. Electrochemical Doping of Halide Perovskites by Noble Metal Interstitial Cations

Author

Kerner, Ross A., primary, Cohen, Ayala V., additional, Xu, Zhaojian, additional, Kirmani, Ahmad R., additional, Park, So Yeon, additional, Harvey, Steven P., additional, Murphy, John P., additional, Cawthorn, Robert C., additional, Giebink, Noel C., additional, Luther, Joseph M., additional, Zhu, Kai, additional, Berry, Joseph J., additional, Kronik, Leeor, additional, and Rand, Barry P., additional

Published
2023
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11. Electrochemical Doping of Halide Perovskites by Noble Metal Interstitial Cations

Author

Ross A. Kerner, Ayala V. Cohen, Zhaojian Xu, Ahmad R. Kirmani, So Yeon Park, Steven P. Harvey, John P. Murphy, Robert C. Cawthorn, Noel C. Giebink, Joseph M. Luther, Kai Zhu, Joseph J. Berry, Leeor Kronik, and Barry P. Rand

Subjects
Mechanics of Materials, Mechanical Engineering, General Materials Science
Published
2023

12. Band gaps of halide perovskites from a Wannier-localized optimally tuned screened range-separated hybrid functional

Author

Guy Ohad, Dahvyd Wing, Stephen E. Gant, Ayala V. Cohen, Jonah B. Haber, Francisca Sagredo, Marina R. Filip, Jeffrey B. Neaton, and Leeor Kronik

Subjects
Physics and Astronomy (miscellaneous), General Materials Science
Abstract

The accurate prediction of the band gaps of halide perovskites within density functional theory is known to be challenging. The recently developed Wannier-localized optimally tuned screened range-separated hybrid functional was shown to be highly accurate for fundamental band gaps of standard semiconductors and insulators. This was achieved by selecting the parameters of the functional to satisfy an ansatz that generalizes the ionization potential theorem to the removal of charge from a state that corresponds to a Wannier function. Here, we present applications of the method to the band gaps of typical halide perovskites. We find a satisfyingly small formal mean absolute error of ∼0.1 eV with respect to experimental band gaps and very good agreement with previous many-body perturbation theory calculations.

Published
2023

23. Breakdown of the Static Picture of Defect Energetics in Halide Perovskites: The Case of the Br Vacancy in CsPbBr3

Author

Leeor Kronik, David Egger, Andrew M. Rappe, and Ayala V. Cohen

Subjects
Materials science, Energetics, Halide, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Molecular dynamics, Chemical physics, Picosecond, Vacancy defect, Strong coupling, General Materials Science, Density functional theory, Physical and Theoretical Chemistry, 0210 nano-technology
Abstract

We consider the Br vacancy in CsPbBr3 as a prototype for the impact of structural dynamics on defect energetics in halide perovskites (HaPs). Using first-principles molecular dynamics based on density functional theory, we find that the static picture of defect energetics breaks down; the energy level associated with a Br vacancy is found to be intrinsically dynamic, oscillating by as much as 1 eV on the picosecond time scale at room temperature. These significant energy fluctuations are correlated with the distance between the neighboring Pb atoms across the vacancy and with the electrostatic potential at these Pb atomic sites. We expect this unusually strong coupling of structural dynamics and defect energetics to bear important implications for both experimental and theoretical analyses of defect characteristics in HaPs. It may also hold significant ramifications for carrier transport and defect tolerance in this class of photovoltaic materials.

Published
2019

24. Spatial Phase Distributions in Solution-Based and Evaporated Cs–Pb–Br Thin Films

Author

Robert Lovrincic, Hannah Funk, Oana Cojocaru-Mirédin, Sebastián Caicedo-Dávila, Ayala V. Cohen, René Gunder, Christian Müller, Sergej Levcenco, Michael Sendner, Daniel Abou-Ras, Frederike Lehmann, Alexandra Franz, Leeor Kronik, Benedikt Haas, and Christoph Koch

Subjects
Methods and concepts for material development, General Energy, Materials science, Phase (matter), Analytical chemistry, Physical and Theoretical Chemistry, Thin film, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Diode
Abstract

In recent years, inorganic cesium amp; 8722;lead amp; 8722;halide perovskites, CsPbX3 X I, Br, Cl , have attracted interest for optoelectronic applications such as highly efficient thin film light emitting diodes or wide gap absorber materials for photovoltaics. However, phase segregation and secondary phases in as deposited thin films are still considered to be limiting factors for devices based on CsPbX3. Here, we report a correlative electron microscopy and spectroscopy approach for the identification of secondary phases and their distributions in Cs amp; 8722;Pb amp; 8722;Br thin films, deposited by solutionbased and coevaporation methods on various substrates. We identified phases by their compositional, structural, and optoelectronic properties, using X ray diffraction, spectroscopy, and a variety of microscopy techniques. We found that the Cs amp; 8722;Pb amp; 8722;Br films contain ternary Cs4PbBr6 and CsPb2Br5 phases in addition to CsPbBr3, a finding consistent with calculations of formation enthalpies by means of the density functional theory showing that these values are very similar for the three ternary phases. We find that these phases can exhibit different spatial distributions inside the film and discuss the influence of the deposition method and synthesis parameters on the resulting phase composition of the Cs amp; 8722;Pb amp; 8722;Br layers

Published
2019

42. Breakdown of the Static Picture of Defect Energetics in Halide Perovskites: the Case of the Br Vacancy in CsPbBr3

Author

Andrew M. Rappe, David Egger, Leeor Kronik, and Ayala V. Cohen

Subjects
Condensed Matter::Materials Science, Condensed Matter - Materials Science, Molecular dynamics, Materials science, Chemical physics, Picosecond, Vacancy defect, Energetics, Strong coupling, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, Halide, Density functional theory
Abstract

We consider the Br vacancy in CsPbBr3 as a prototype for the impact of structural dynamics on defect energetics in halide perovskites (HaPs). Using first-principles molecular dynamics based on density functional theory, we find that the static picture of defect energetics breaks down; the energy of the Br vacancy level is found to be intrinsically dynamic, oscillating by as much as 1 eV on the ps time scale at room temperature. These significant energy fluctuations are correlated with the distance between the neighboring Pb atoms across the vacancy and with the electrostatic potential at these Pb atomic sites. We expect this unusually strong coupling of structural dynamics and defect energetics to bear important implications for both experimental and theoretical analysis of defect characteristics in HaPs. It may also hold significant ramifications for carrier transport and defect tolerance in this class of photovoltaic materials., 5 figures, 1 table

Published
2018

46. Comparing UAV-Based Technologies and RGB-D Reconstruction Methods for Plant Height and Biomass Monitoring on Grass Ley

Author

Ministerio de Economía y Competitividad (España), Research Council of Norway, Norwegian Institute of Bioeconomy Research, Rueda-Ayala, Victor P. [0000-0002-9159-8276], Peña, Jose M. [0000-0003-4592-3792], Höglind, Mats [0000-0002-7474-8789], Bengochea-Guevara, José María [0000-0003-4081-7325], Andújar, Dionisio [0000-0002-5801-0944], Rueda-Ayala, V. P., Peña, J. M., Höglind, M., Bengochea-Guevara, José M., Andújar, Dionisio, Ministerio de Economía y Competitividad (España), Research Council of Norway, Norwegian Institute of Bioeconomy Research, Rueda-Ayala, Victor P. [0000-0002-9159-8276], Peña, Jose M. [0000-0003-4592-3792], Höglind, Mats [0000-0002-7474-8789], Bengochea-Guevara, José María [0000-0003-4081-7325], Andújar, Dionisio [0000-0002-5801-0944], Rueda-Ayala, V. P., Peña, J. M., Höglind, M., Bengochea-Guevara, José M., and Andújar, Dionisio

Abstract

Pastures are botanically diverse and difficult to characterize. Digital modeling of pasture biomass and quality by non-destructive methods can provide highly valuable support for decision-making. This study aimed to evaluate aerial and on-ground methods to characterize grass ley fields, estimating plant height, biomass and volume, using digital grass models. Two fields were sampled, one timothy-dominant and the other ryegrass-dominant. Both sensing systems allowed estimation of biomass, volume and plant height, which were compared with ground truth, also taking into consideration basic economical aspects. To obtain ground-truth data for validation, 10 plots of 1 m² were manually and destructively sampled on each field. The studied systems differed in data resolution, thus in estimation capability. There was a reasonably good agreement between the UAV-based, the RGB-D-based estimates and the manual height measurements on both fields. RGB-D-based estimation correlated well with ground truth of plant height ( R 2 > 0.80 ) for both fields, and with dry biomass ( R 2 = 0.88 ), only for the timothy field. RGB-D-based estimation of plant volume for ryegrass showed a high agreement ( R 2 = 0.87 ). The UAV-based system showed a weaker estimation capability for plant height and dry biomass ( R 2 < 0.6 ). UAV-systems are more affordable, easier to operate and can cover a larger surface. On-ground techniques with RGB-D cameras can produce highly detailed models, but with more variable results than UAV-based models. On-ground RGB-D data can be effectively analysed with open source software, which is a cost reduction advantage, compared with aerial image analysis. Since the resolution for agricultural operations does not need fine identification the end-details of the grass plants, the use of aerial platforms could result a better option in grasslands.

Published
2019

49. Spatial Phase Distributions in Solution-Based and Evaporated Cs–Pb–Br Thin Films

Author

Caicedo-Dávila, Sebastián, primary, Funk, Hannah, additional, Lovrinčić, Robert, additional, Müller, Christian, additional, Sendner, Michael, additional, Cojocaru-Mirédin, Oana, additional, Lehmann, Frederike, additional, Gunder, René, additional, Franz, Alexandra, additional, Levcenco, Sergej, additional, Cohen, Ayala V., additional, Kronik, Leeor, additional, Haas, Benedikt, additional, Koch, Christoph T., additional, and Abou-Ras, Daniel, additional

Published
2019
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50. Lipidomics Reveals a Tissue-Specific Fingerprint

Author

Pradas, I, Huynh, K, Cabre, R, Ayala, V, Meikle, PJ, Jove, M, Pamplona, R, Pradas, I, Huynh, K, Cabre, R, Ayala, V, Meikle, PJ, Jove, M, and Pamplona, R

Abstract

In biological systems lipids generate membranes and have a key role in cell signaling and energy storage. Therefore, there is a wide diversity of molecular lipid expressed at the compositional level in cell membranes and organelles, as well as in tissues, whose lipid distribution remains unclear. Here, we report a mass spectrometry study of lipid abundance across 7 rat tissues, detecting and quantifying 652 lipid molecular species from the glycerolipid, glycerophospholipid, fatty acyl, sphingolipid, sterol lipid and prenol lipid categories. Our results demonstrate that every tissue analyzed presents a specific lipid distribution and concentration. Thus, glycerophospholipids are the most abundant tissue lipid, they share a similar tissue distribution but differ in particular lipid species between tissues. Sphingolipids are more concentrated in the renal cortex and sterol lipids can be found mainly in both liver and kidney. Both types of white adipose tissue, visceral and subcutaneous, are rich in glycerolipids but differing the amount. Acylcarnitines are mainly in the skeletal muscle, gluteus and soleus, while heart presents higher levels of ubiquinone than other tissues. The present study demonstrates the existence of a rat tissue-specific fingerprint.

Published
2018

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