71 research outputs found

    Psychological wellbeing in chronic disease from a gender perspective: psychosocial variables and brief psychological interventions

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    La transición epidemiológica en occidente ha supuesto grandes cambios en los patrones de morbi-mortalidad, con un aumento exponencial de las enfermedades no transmisibles (ENT). Esto provocó un cambio en la concepción de salud hacia una perspectiva más integradora, en la que los factores biopsicosociales eran necesarios para explicar los procesos de salud-enfermedad y las personas por tanto se convertían en agentes activos, en responsables más que meros sujetos pasivos a la espera de recibir medicación. Las enfermedades cardiovasculares (ECV) son el conjunto de ENT más prevalente y con una mayor tasa de mortalidad a nivel mundial. Históricamente han sido consideradas enfermedades masculinas, aunque las estadísticas muestran una mayor mortalidad en mujeres. Esta brecha de sexo en las ECV parece venir determinada por un sesgo de género que afecta al diagnóstico e intervención y hace necesaria una perspectiva de género a la hora de abordarlas. Estas enfermedades son el claro ejemplo de la necesidad de entender la salud de manera integral, ya que los principales factores de riesgo cardiovascular son modificables y, por tanto, prevenibles. Uno de los objetivos de la Psicología de la Salud es precisamente conocer los factores subyacentes que influyen en el comportamiento saludable de este tipo de pacientes con el fin de promoverlo. En esta dirección, numerosas investigaciones han relacionado las conductas saludables con variables psicológicas como la autoeficacia, una regulación emocional adecuada o el bienestar psicológico, que se vinculan con un mayor compromiso terapéutico y cambios saludables en el estilo de vida. A su vez, las ECV se han encontrado relacionadas con unos niveles altos de ansiedad, estrés y depresión, y estas se relacionan asimismo con un peor pronóstico de la enfermedad y una peor calidad de vida en estos pacientes. Por esta relación entre factores psicológicos y determinantes de salud cardiovascular, se necesitan intervenciones dirigidas a intentar promover estas variables psicológicas con el objetivo de mejorar su ajuste a la enfermedad y la reducción del riesgo cardiovascular. En esta línea, y partiendo de los prometedores resultados de la telemedicina para promover conductas saludables, es necesario conocer si este tipo de intervenciones serían eficaces para mejorar las variables psicológicas antes mencionadas en pacientes con ECV. De igual modo, la brecha de salud entre mujeres y hombres hace necesaria la implementación de una perspectiva de género en la investigación e intervención sobre la misma. Por todo lo anterior, la presente Tesis Doctoral tiene como objetivo profundizar en el análisis de los factores psicosociales que afectan a la salud y que se relacionan con la ECV, así como poner a prueba la eficacia de intervenciones mHealth para promover las variables psicológicas que se relacionan con los comportamientos saludables y el bienestar psicológico de esta población. Se proponen, por tanto, una serie de investigaciones que se han materializado en la publicación de tres artículos científicos independientes e interrelacionados, los cuales se presentan a continuación. El primer estudio es una revisión sistemática que tiene como objetivo explorar los factores psicosociales que se han estudiado para explicar la vulnerabilidad diferencial del bienestar psicológico en mujeres y hombres. Partiendo de un modelo biopsicosocial, complementado con la perspectiva de género, se incluyeron estudios que evaluaban las diferencias de sexo y género en la ansiedad y su comorbilidad. Siguiendo la metodología PRISMA, se realizó una búsqueda sistemática en las bases de datos electrónicas PubMed y PsycInfo, incorporando estudios empíricos y revisiones publicadas entre 2008 - 2021. Tras la búsqueda, 44 estudios fueron incluidos, los cuales se analizaron y clasificaron en función del objeto de estudio. Finalmente, se realizó una síntesis narrativa cualitativa de los resultados. Los resultados de los estudios incluidos mostraron que las diferencias en la vulnerabilidad psicológica entre sexos se han analizado históricamente a partir de factores biológicos o factores de corte psicosocial; sin embargo, estudios que abordasen la problemática aludiendo de manera conjunta a ambos factores fueron escasos El segundo estudio tiene como objetivo evaluar la efectividad de una intervención psicológica mHealth en regulación emocional para mejorar el afecto positivo y la autoeficacia en personas con ECV. Para ello, se diseñó un ensayo controlado no aleatorizado de dos brazos, en el que la muestra de 69 pacientes cardiovasculares participó en un grupo experimental o un grupo control o de tratamiento habitual. La intervención, basada en el proceso de regulación emocional (Gross, 1998; Leahy, 2011), está conformada por dos fases. La primera consistió en una sesión presencial y la segunda en una intervención basada en mHealth de 14 días. Ambos grupos fueron evaluados en múltiples ocasiones en afecto positivo y autoeficacia (crónica y cardíaca), incluyendo dos follow-ups, lo que permitió un análisis de medidas repetidas. Los resultados indican que la intervención psicológica mHealth fue efectiva para mejorar el afecto positivo y la autoeficacia en pacientes con ECV, encontrándose diferencias intragrupo y entre grupos. El tercer estudio es un ensayo clínico piloto no aleatorizado, que tiene como objetivo diseñar y evaluar la efectividad de una intervención mHealth multicomponente en autoeficacia para mejorar el bienestar subjetivo y la autoeficacia para el manejo de la enfermedad cardíaca y crónica, analizando además posibles diferencias entre hombres y mujeres. Para este estudio, la muestra estaba compuesta por 42 pacientes cardiovasculares, que participaron equitativamente en un grupo experimental o control. Esta intervención multicomponente fue diseñada en base a la autoeficacia (Bandura, 1986a) e incluye una sesión presencial personalizada y una intervención mHealth de 14 días. Al igual que en el segundo estudio, ambos grupos fueron evaluados en repetidas ocasiones, con dos evaluaciones follow-ups que permitieron hacer comparaciones entre grupos e intragrupo, y ofrecer información más precisa acerca de la efectividad de la intervención. Los resultados mostraron que esta fue efectiva para mejorar el afecto positivo y la autoeficacia para el manejo de la enfermedad en pacientes cardiovasculares. Sin embargo, cuando se analizaron los datos por sexo, se observó que esta efectividad se daba únicamente en la población masculina. En conjunto, los resultados derivados de los tres estudios que conforman la presente tesis doctoral ponen de manifiesto la necesidad de incorporar el modelo biopsicosocial, así como la perspectiva de género, para comprender los procesos de salud enfermedad y abordar el diagnóstico y tratamiento de enfermedades de largo alcance como lo son las ECV, y su relación con la salud mental. Por su parte, los estudios empíricos aportan evidencia en favor de las vertientes terapéuticas que demandan la inclusión de la psicología en la rehabilitación cardíaca, además de la incorporación de nuevas estrategias de intervención que garanticen la accesibilidad de la atención sanitaria a este tipo de pacientes. Se considera que investigaciones futuras, por otro lado, deberían poner el foco en cómo establecer intervenciones online sin perder el contacto humano, así como tratar de adentrarse completamente en la personalización de estas intervenciones buscando evitar las diferencias en efectividad para las mujeres y la obtención de mejores resultados terapéuticos.The epidemiological transition in Western countries has led to major changes in morbidity and mortality patterns, with an exponential increase in non-communicable diseases (NCDs). This led to a change in the conception of health towards a more integrative perspective, in which biopsychosocial factors were necessary to explain the health disease processes and people, therefore, became active agents, responsible rather than mere passive subjects waiting to receive medication. Cardiovascular diseases (CVD) are the most prevalent set of NCDs with the highest mortality rate worldwide. They have historically been considered male diseases, although statistics show a higher mortality in women. This gender gap in CVD seems to be determined by a gender bias that affects diagnosis and intervention and makes a gender perspective necessary when addressing them. These diseases are a clear example of the need for a holistic approach to health, as the main cardiovascular risk factors are modifiable and, therefore, preventable. One of the objectives of Health Psychology is precisely to understand the underlying factors that influence healthy behaviour of these patients in order to promote them. In this direction, numerous investigations have related healthy behaviours to psychological variables, such as self-efficacy, adequate emotional regulation or psychological well-being, which are linked to greater therapeutic commitment and healthy lifestyle changes. In turn, CVD has been found to be associated with high levels of anxiety, stress and depression, which are also related to a worse prognosis of the disease and a poorer quality of life in these patients. Due to this relationship between psychological factors and cardiovascular health determinants, interventions aimed at promoting these psychological variables with the objective of improving their adjustment to the disease and reducing cardiovascular risk are deemed necessary. In this line, and based on the promising results of telemedicine to promote healthy behaviours, it is necessary to know whether this type of intervention would be effective in improving the aforementioned psychological variables in patients with CVD. Similarly, the health gap between women and men makes it necessary to implement a gender perspective in research and intervention. For all of the above reasons, the aim of this doctoral thesis is to deepen the analysis of the psychosocial factors that affect health and are related to CVD, as well as to test the effectiveness of mHealth interventions to promote the psychological variables related to healthy behaviours and psychological well-being in these patients. Thus, a series of investigations are proposed. These investigations have materialised in the publication of three independent and interrelated scientific articles, which are presented below. The first study is a systematic review that aims to explore the psychosocial factors that have been studied to explain the differential vulnerability of psychological well-being in women and men. Based on a biopsychosocial model, complemented by the gender perspective, studies assessing sex and gender differences in anxiety and its comorbidity were included. Following the PRISMA methodology, a systematic search was conducted in the electronic databases PubMed and PsicInfo, incorporating empirical studies and reviews published between 2008 - 2021. Following the search, 44 studies were included, which were analysed and classified according to the object of study. Finally, a qualitative narrative synthesis of the results was conducted. The results of the included studies showed that differences in psychological vulnerability between the sexes have historically been analysed on the basis of biological factors or psychosocial factors, but few studies have addressed the problem by alluding to both factors together. The second study aims to evaluate the effectiveness of an mHealth psychological intervention in emotional regulation to improve positive affect and self-efficacy in patients with CVD. To this end, a two-arm, non-randomised controlled trial was designed, in which the sample of 69 CVD patients was assigned to either the experimental group or the control or treatment-as-usual group. The intervention, based on the emotional regulation process (Gross, 1998; Leahy, 2011), consists of two phases, a face-to-face session and a second 14-day mHealth phase. Both groups were assessed multiple times on positive affect and self-efficacy (chronic and cardiac), including two follow-ups, which allowed for a repeated measures analysis. The results indicate that the mHealth psychological intervention was effective in improving positive affect and self-efficacy in patients with cardiovascular disease, with intra-group and between-group differences found. The third study is another pilot non-randomised clinical trial, which aims to design and evaluate the effectiveness of a multicomponent mHealth intervention on self-efficacy in improving subjective well-being and self-efficacy for the management of cardiac and chronic disease, also analysing possible differences between men and women. For this study, the sample consisted of 42 cardiovascular patients, who were equally assigned to the control or experimental group. This multicomponent intervention was designed on the basis of self-efficacy (Bandura, 1986a) and included a face-to-face one-to-one session and a 14-day mHealth intervention. As in the second study, both groups were repeatedly evaluated, with two follow-up assessments allowing for between-group and within-group comparisons and providing more accurate information about the effectiveness of the intervention. The results showed that the intervention was effective in improving positive affect and self-efficacy for disease management in cardiovascular patients. However, when the data were analysed by gender, this effectiveness was found to occur only in the male population. Taken together, the results derived from the three studies that constitute this doctoral thesis highlight the need to incorporate the biopsychosocial model, as well as a gender perspective, in order to understand health-disease processes and to address the diagnosis and treatment of long-term diseases, such as CVD, and their relation with mental health. With regards to the empirical studies, they provide evidence in favor of the therapeutic aspects that demand the inclusion of psychology in cardiac rehabilitation, as well as the incorporation of new intervention strategies that guarantee the accessibility of health care for these patients. Future research, on the other hand, should focus on how to establish online interventions without losing human contact, as well as try to fully explore the personalization of these interventions in order to avoid differences in effectiveness for women and to obtain better therapeutic results

    Health, stress and technologies: integrating technology acceptance and health belief models for smartphone-based stress intervention

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    Work-related stress significantly jeopardizes employees’ physical and mental health due to the considerable time they spend at work. Smartphone-based interventions provide a promising solution, eliminating traditional face-to-face interventions’ barriers. However, the elements that influence workers’ intentions to use this still remain unexplored. This study explores the link between health belief model (HBM) and technology acceptance model (TAM) factors. In this study, 336 Italian workers (64% female) answered an online questionnaire. We employed a structural equation model (SEM) to analyze the data. The results unveiled an indirect relationship: individuals perceiving health risks were more inclined to use stress-management apps, mediated by perceived utility (PU). This study underscores the significant potential of integrating the HBM with the TAM in predicting users’ preparedness for smartphone-based health interventions. These findings not only hold substantial value but also illuminate a path forward for professionals and organizations, offering insights to tailor and optimize smartphone tools for stress management and the promotion of workplace well-being. Ultimately, this research paves the way for the cultivation of healthier work environments, marking a noteworthy contribution to the field

    Membranoproliferative glomerulonephritis recurrence after kidney transplantation: using the new classification.

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    BACKGROUND: Membranoproliferative glomerulonephritis (MPGN) is an uncommon glomerular disorder that may lead to end stage renal disease (ESRD). With new understanding of the disease pathogenesis, the classical classification as MPGN types I, II, III has changed. Data on post-transplant MPGN, in particular with the newly refined classification, is limited. We present our center\u27s experience of MPGN after kidney transplantation using the new classification. METHODS: This is a retrospective study of 34 patients with ESRD due to MPGN who received 40 kidney transplants between 1994 and 2014. We reviewed the available biopsies\u27 data using the new classification. We assessed post transplantation recurrence rate, risk factors of recurrence, the response to therapy and allografts\u27 survival. RESULTS: Median time of follow up was 5.3 years (range 0.5-14 years). Using the new classification, we found that pre-transplant MPGN disease was due to immune complex-mediated glomerulonephritis (ICGN) in 89 % of cases and complement-mediated glomerulonephritis (CGN) in 11 %. Recurrence was detected in 18 transplants (45 %). Living related allografts (P = 0.045), preemptive transplantations (P = 0.018), low complement level (P = 0.006), and the presence of monoclonal gammopathy (P = 0.010) were associated with higher recurrence rate in ICGN cases. Half of the patients with recurrence lost their allografts. The use of ACEi/ARB was associated with a trend toward less allograft loss. CONCLUSIONS: MPGN recurs at a high rate after kidney transplantation. The risk of MPGN recurrence increases with preemptive transplantation, living related donation, low complement level, and the presence of monoclonal gammopathy. Recurrence of MPGN leads to allograft failure in half of the cases

    El rol moderador de la eficacia percibida de las medidas de prevención frente al COVID-19 en la relación entre la percepción de riesgo y la salud mental percibida.

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    The pandemic situation caused by COVID-19 led countries to adopt harsh and prolonged (over time) measures that—along with the high number of infections and deaths and continuous negative information—have affected the mental health of individuals. In this study, the impact on mental health of the COVID-19 health crisis in Spain was explored through the perceived efficacy of pandemic containment measures as a moderator of the relationship that COVID-19 perceived risk establishes with stress and depression. A questionnaire composed of scales conceived to measure COVID-19 perceived risk, perceived efficacy of COVID-19 prevention measures, stress, and depression was completed by 478 adults living in Spain (66.9% females, Mage = 36.30, SD = 15.32) between May 16, 2021, and June 6, 2021. The results confirmed the moderating role of perceived efficacy. Perceived efficacy acted as a protective factor for stress and depression by decreasing the negative impact that perceived risk had on both variables related to mental distress. Also, the perception that participants had about the effectiveness of prevention measures appeared to be a relevant protective factor regarding mental health during the pandemic. This study highlights the relevance of psychological interventions and government policies that improve positive risk communication and provide adequate information regarding the effectiveness of health-prevention measures.La pandemia del COVID-19 ha llevado a los países a adoptar severas y prolongadas medidas que —junto con el alto número de contagios y muertes y la continua información negativa— ha afectado la salud mental de las personas. Este estudio analiza el impacto de la crisis sanitaria del COVID-19 en España explorando el rol moderador de la eficacia percibida de las medidas de contención en la relación que establece la percepción del riesgo del COVID-19 con el estrés y la depresión. Un total de 478 adultos residentes en España (un 66.9% mujeres; Medad = 36.30, DT = 15.32) completaron un cuestionario con escalas concebidas para medir el riesgo percibido del COVID-19, la eficacia percibida de las medidas de protección, el estrés y la depresión entre el 16 de mayo y el 6 de junio de 2021. Los resultados confirmaron el rol moderador de la eficacia percibida, la cual actuó como un factor protector del estrés y la depresión al disminuir el impacto negativo que la percepción de riesgo del COVID-19 tiene en ambas variables relacionadas con el distrés mental. La percepción que tienen los individuos sobre la efectividad de las medidas de protección parece ser un factor protector relevante en relación con la salud mental durante una pandemia. Se subraya la relevancia de intervenciones psicológicas y de políticas gubernamentales que mejoren la comunicación positiva del riesgo y la información adecuada sobre la eficacia de las medidas de protección

    El rol moderador de la eficacia percibida de las medidas de prevención frente al COVID-19 en la relación entre la percepción de riesgo y la salud mental percibida

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    The pandemic situation caused by COVID-19 led countries to adopt harsh and prolonged (over time) measures that—along with the high number of infections and deaths and continuous negative information—have affected the mental health of individuals. In this study, the impact on mental health of the COVID-19 health crisis in Spain was explored through the perceived efficacy of pandemic containment measures as a moderator of the relationship that COVID-19 perceived risk establishes with stress and depression. A questionnaire composed of scales conceived to measure COVID-19 perceived risk, perceived efficacy of COVID-19 prevention measures, stress, and depression was completed by 478 adults living in Spain (66.9% females, Mage= 36.30, SD= 15.32) between May 16, 2021, and June 6, 2021. The results confirmed the moderating role of per-ceived efficacy. Perceived efficacy acted as a protective factor for stress and depression by decreasing the negative impact that perceived risk had on both variables related to mentaldistress. Also, the perception that participants had about the effectiveness of prevention measures appeared to be a relevant protective factor regarding mental health during the pandemic. This study highlights the relevance of psychological interventions and government policies that improve positive risk communication and provide adequate information regarding the effectiveness of health-prevention measuresLa pandemia del COVID-19 ha llevado a los países a adoptar severas y prolongadas medidas que junto con el alto número de contagios y muertes y la continua información negativa ha afectado la salud mental de las personas. Este estudio analiza el impacto de la crisis sanitaria del COVID-19 en España explorando el rol moderador de la eficacia percibida de las medidas de contención en la relación que establece la percepción del riesgo del COVID-19 con el estrés y la depresión. Un total de 478 adultos residentes en España (un66.9% mujeres; Medad= 36.30, DT= 15.32) completaron un cuestionario con escalas concebidas para medir el riesgo percibido del COVID-19, la eficacia percibida de las medidas de protección, el estrés y la depresión entre el 16 de mayo y el 6 de junio de 2021. Los resultados confirmaron el rol moderador de la eficacia percibida, la cual actuó como un factor protector del estrés y la depresión al disminuir el impacto negativo que la percepción de riesgo del COVID-19 tiene en ambas variables relacionadas con el distrés mental. La percepción que tienen los individuos sobre la efectividad de las medidas de protección parece ser un factor protector relevante en relación con la salud mental durante una pandemia. Se subraya la relevancia de intervenciones psicológicas y de políticas gubernamentales que mejoren la comunicación positiva del riesgo y la información adecuada sobre la eficacia de las medidas de protección

    Positivity and health locus of control: key variables to intervene on well-being of cardiovascular disease patients

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    Psychological well-being is a good predictor of several health outcomes in cardiovascular disease patients (adherence, quality of life, and healthy behaviors). The perception of health control and a positive orientation seem to have a beneficial effect on health and well-being. Therefore, the aim of this study was to investigate the role of the health locus of control and positivity in the psychological well-being and quality of life of cardiovascular patients. A total of 593 cardiac outpatients completed the Multidimensional Health Locus of Control Scale, the Positivity Scale and the Hospital Anxiety and Depression Scale at baseline (January 2017) and 9 m later (follow-up; n = 323). A Spearman rank correlation coefficient and a structural equation modeling approach were determined to explore the relationships between those variables both cross-sectionally and longitudinally. A cross-sectional correlation analysis at baseline revealed that the internal health locus of control and positivity were negatively associated with anxiety (rs = −0.15 and −0.44, ps < 0.01) and depression (rs = −0.22 and −0.55, ps < 0.01) and positively associated with health-related quality of life (rs = 0.16 and 0.46, ps < 0.01). Similar outcomes were found at follow-up and in longitudinal correlations. According to the path analysis, positivity was found to be negatively associated with anxiety and depression level at baseline (β = −0.42 and −0.45, ps < 0.001). Longitudinally, positivity was negatively associated with depression (β = 0.15, p < 0.01) and together with the internal health locus of control, was positively associated with health-related quality of life (β = 0.16 and 0.10, respectively, ps < 0.05). These findings suggest that focusing on the health locus of control and especially positivity may be crucial in enhancing the psychological well-being of patients in the context of cardiac care. The potential impact of these results on future interventions is discussed

    PHYTOPHENOLICS COMPOSITION, HYPOLIPIDEMIC, HYPOGLYCEMIC AND ANTIOXIDATIVE EFFECTS OF THE LEAVES OF FORTUNELLA JAPONICA (THUNB.) SWINGLE

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    Objective: Fortunella japonica (Thunb.) Swingle is an evergreen shrub, its whole fruit, including the peel, is eaten. There have been few detailed phytophenolics composition reports on this genus and the hypoglycemic and hypolipidemic effects of the plant were not evaluated. Methods: Structures of the isolated compounds were elucidated by spectral analysis. Serum glucose level, activities of liver enzymes, total protein content, serum lipid profiles, antioxidant parameters and some glycolytic and gluconeogenic enzymes in streptozotocin (STZ)-induced diabetic rats were determined. The evaluation also carried out through determination of liver disorder biomarkers and histopathological examination of liver, kidney and pancreas. Results: Six phytophenolics were isolated, for the first time from the genus Fortunella as well as a sterol compound. Treatment with the ethanolic extract of F. japonica leaves effectively meliorated antioxidant markers and glycolytic enzymes. The histopathological analyzes also confirmed the experimental findings.Conclusion: The results show that the ethanolic extract has hypoglycemic, hypotriglyceridemic and antioxidant effects in STZ-induced diabetic rats, suggesting that this extract supplementation can be useful in preventing diabetic complications associated with hyperlipidemia and oxidative stress.Â

    Evaluation of Protective and Antioxidant Activity of Thyme (Thymus Vulgaris) Extract on Paracetamol-Induced Toxicity in Rats

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    Abstract: Paracetamol is a common analgesic and antipyretic drug which is safe in therapeutic doses but can produce life-threatening hepatic and renal damages with toxic doses. The current study was designed to investigate the protective effects of aqueous extract of thyme (Thymus Vulgaris) against paracetamol-induced toxicity in male albino rats. A total of 24 rats were used for the study. The rats were grouped into four with sex rats in each group. Group I was the control, group II received thyme extract at a dose of 500 mg / kg body weight for 14 days. group III received paracetamol at a dose of 200 mg / kg body weight / ml without extract for 14 days, and group IV received paracetamol plus thyme extract for 14 days. Administration of paracetamol to rats induced marked disturbance of hepatic and renal functions, characterized by a significant increase in the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP),total bilirubin , total protein , blood urea and serum creatinine (p &lt; 0.01) and injured the hepatic and renal cells evident from increased level of malondialdehyde (MDA) (p &lt; 0.01) along with depletion of super oxide dismutase (SOD), catalase (CAT), activities and reduced glutathione (GSH) levels (p &lt; 0.01). Histopathological changes showed that paracetamol caused significant structural damages to liver and kidneys. Oral co-administration of thyme extract with paracetamol significantly decreased the level of liver enzymes (ALT, AST and ALP), total bilirubin , total protein, blood urea and creatinine. The increased levels of lipid peroxidation in tissues were reverted significantly. Thyme treatment also resulted in a significant increased in CAT, SOD and GSH in both liver and kidneys. Moreover, thyme extract also exhibited some improvement in the histological architecture of liver and kidney . These results clearly show the antioxidant and protective property of thyme extract

    Non-ambiguous recovery of Biot poroelastic parameters of cellular panels using ultrasonic waves

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    a b s t r a c t The inverse problem of the recovery of the poroelastic parameters of open-cell soft plastic foam panels is solved by employing transmitted ultrasonic waves (USW) and the Biot-Johnson-Koplik-Champoux-Allard (BJKCA) model. It is shown by constructing the objective functional given by the total square of the difference between predictions from the BJKCA interaction model and experimental data obtained with transmitted USW that the inverse problem is ill-posed, since the functional exhibits several local minima and maxima. In order to solve this problem, which is beyond the capability of most off-the-shelf iterative nonlinear least squares optimization algorithms (such as the Levenberg Marquadt or Nelder-Mead simplex methods), simple strategies are developed. The recovered acoustic parameters are compared with those obtained using simpler interaction models and a method employing asymptotic phase velocity of the transmitted USW. The retrieved elastic moduli are validated by solving an inverse vibration spectroscopy problem with data obtained from beam-like specimens cut from the panels using an equivalent solid elastodynamic model as estimator. The phase velocities are reconstructed using computed, measured resonance frequencies and a time-frequency decomposition of transient waves induced in the beam specimen. These confirm that the elastic parameters recovered using vibration are valid over the frequency range of study
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