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OBJECTIVES: To examine how change in benzodiazepine (BZD) use is linked to changes in depressive symptoms intensity, worry intensity, and sleep quality over 16 months. METHOD: Data come from a larger randomised controlled trial (RCT) named the 'Programme d'Aide du Succès au SEvrage (PASSE-60+)' study (NCT02281175). Seventy-three participants age 60 years and older took part in a 4-month discontinuation programme and were assessed four times over 16 months. Change in BZD use was defined as the difference in reported mg/day between two assessments. Control variables were RCT discontinuation group; BZD use at T1; and either depressive symptoms, worry intensity, or sleep quality at T1. Hierarchical multiple regressions were used to analyse data. RESULTS: In the short term, right after the discontinuation programme, sleep quality worsened with lower BZD use. This link was no longer significant at the 3- and 12-month follow-up. In the long term, depressive symptoms lowered with lower BZD use. No change was found in worry intensity in relation to BZD use at all measurement times. CONCLUSION: Discontinuation may improve depressive symptoms. Our study also questions the long-term effectiveness of BZD use, since long-term discontinuation was not linked with change in worry intensity and sleep quality.
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Benzodiazepinas , Depressão , Humanos , Masculino , Feminino , Idoso , Depressão/tratamento farmacológico , Benzodiazepinas/administração & dosagem , Benzodiazepinas/uso terapêutico , Pessoa de Meia-Idade , Qualidade do Sono , Ansiedade/tratamento farmacológico , Idoso de 80 Anos ou maisRESUMO
The environmental and health-related impacts of synthetic dyes have led to growing interest in natural dyes as sustainable and eco-friendly alternatives. However, natural dyes have been used to dye textiles with limited color shade and poor fastness properties, and little research has been conducted in this field. Additionally, natural dyes also have the potential to provide added functionalities to textiles, such as antibacterial and anti-UV properties. A systematic literature review of 38 studies was conducted to analyze the use of six natural dyes derived from eucalyptus (Eucalyptus globulus Labill.), weld (Reseda luteola L.), madder (Rubia tinctorum L.), annatto (Bixa Orellana L.), true indigo (Indigofera tinctoria L.) and woad (Isatis tinctoria L.). These dyes were selected after a preliminary analysis of studies on plant-based natural dyes with primary colors, considering their chromatic and potential medicinal properties. This study explores the influence of different dyeing parameters and auxiliary products in these properties. The research discussed how the chromatic and medicinal properties of natural dyes can be affected by various factors and provides a summary table with the chromatic palette possibilities according to the different materials and processes relationships. Exploring the combination of natural dyes with environmentally friendly auxiliary products can be a promising development area for creating a wide range of color shades. Further research is also needed to optimize the dyeing processes with natural dyes, towards more sustainable textile dyeing possibilities.
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The growing trend towards high voltage electrical assets and propulsion in the aeronautics and space industry pose new challenges in electrical insulation materials that cannot be overlooked. Transition to new high voltage electrified systems with unprecedented high levels of voltage, power, and efficiency must be safe and reliable. Improvements in both performance and safety of megawatt power systems is complicated because of the need for additional power transmission wiring and cabling and new safety requirements that have the potential of making the resulting systems heavier. To mitigate this issue, novel lightweight materials and system solutions are required that would result in lower specific weights in the insulator and conductor. Although reduced size and weight of system components can be achieved with new concepts, designs, and technologies, the high voltage (≥300 V) operation presents a significant challenge. This challenge is further complicated when considering the extreme operating environment that is experienced in aircraft, spacecraft, and targeted human exploration destinations. This paper reviews the extreme environmental challenges for aerospace electrical insulation and the needs associated with operating under high voltage and extreme environments. It also examines several recently developed robust lightweight electrical insulation materials that could enhance insulation performance and life. In aerospace, research must consider mass when developing new technologies. The impact of these recent developments provides a pathway which could enable next generation high altitude all electric aircraft, lightweight power transmission cables for a future sustained presence on the Moon and missions to Mars using HV propulsion, such as spacecraft with Nuclear Electric Propulsion systems.
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Despite US federal legislation mandates institutions to provide meaningful access and participation to students and families in educational settings, culturally and linguistically diverse (CLD) families and caregivers of children in special education experience cultural and linguistic barriers. A Community Advisory Team (CAT) of parents, advocates, community interpreters and translators, researchers, and teachers explored CLD families' experiences and advocacy efforts. Critical bifocality and circuits of dispossession, privilege, and resistance informed the documentation of inequities and resistance to understand the linkages of structural arrangements of power. Focus groups with families (n = 21) speakers of Spanish, Portuguese, and Cantonese were conducted. Findings indicate perceived discrimination, poor and inadequate interpretation and translation services impact children's access to special education services, hinder family's communication with schools and reduce the perceptions of schools as trustworthy institutions. Families advocate relentlessly for their children and recommend schools listen to families and hire culturally and linguistically competent interpreters and translators. Community psychologists can make significant contributions to promote language justice in education settings through participatory approaches to inquiry that value CLD families' knowledge and expertise.
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Emigrantes e Imigrantes , Idioma , Humanos , Justiça Social , Comunicação , Grupos FocaisRESUMO
BACKGROUND: The use of COVID-19 vaccines has been prioritised to protect the most vulnerable-notably, older people. Because of fluctuations in vaccine availability, strategies such as delayed second dose and heterologous prime-boost have been used. However, the effectiveness of these strategies in frail, older people are unknown. We aimed to assess the antigenicity of mRNA-based COVID-19 vaccines in frail, older people in a real-world setting, with a rationed interval dosing of 16 weeks between the prime and boost doses. METHODS: This prospective observational cohort study was done across 12 long-term care facilities of the Montréal Centre-Sud - Integrated University Health and Social Services Centre in Montréal, Québec, Canada. Under a rationing strategy mandated by the provincial government, adults aged 65 years and older residing in long-term care facilities in Québec, Canada, with or without previously documented SARS-CoV-2 infection, were administered homologous or heterologous mRNA vaccines, with an extended 16-week interval between doses. All older residents in participating long-term care facilities who received two vaccine doses were eligible for inclusion in this study. Participants were enrolled from Dec 31, 2020, to Feb 16, 2021, and data were collected up to June 9, 2021. Clinical data and blood samples were serially collected from participants at the following timepoints: at baseline, before the first dose; 4 weeks after the first dose; 6-10 weeks after the first dose; 16 weeks after the first dose, up to 2 days before administration of the second dose; and 4 weeks after the second dose. Sera were tested for SARS-CoV-2-specific IgG antibodies (to the trimeric spike protein, the receptor-binding domain [RBD] of the spike protein, and the nucleocapsid protein) by automated chemiluminescent ELISA. Two cohorts were used in this study: a discovery cohort, for which blood samples were collected before administration of the first vaccine dose and longitudinally thereafter; and a confirmatory cohort, for which blood samples were only collected from 4 weeks after the prime dose. Analyses were done in the discovery cohort, with validation in the confirmatory cohort, when applicable. FINDINGS: The total study sample consisted of 185 participants. 65 participants received two doses of mRNA-1273 (Spikevax; Moderna), 36 received two doses of BNT162b2 (Comirnaty; Pfizer-BioNTech), and 84 received mRNA-1273 followed by BNT162b2. In the discovery cohort, after a significant increase in anti-RBD and anti-spike IgG concentrations 4 weeks after the prime dose (from 4·86 log binding antibody units [BAU]/mL to 8·53 log BAU/mL for anti-RBD IgG and from 5·21 log BAU/mL to 8·05 log BAU/mL for anti-spike IgG), there was a significant decline in anti-RBD and anti-spike IgG concentrations until the boost dose (7·10 log BAU/mL for anti-RBD IgG and 7·60 log BAU/mL for anti-spike IgG), followed by an increase 4 weeks later for both vaccines (9·58 log BAU/mL for anti-RBD IgG and 9·23 log BAU/mL for anti-spike IgG). SARS-CoV-2-naive individuals showed lower antibody responses than previously infected individuals at all timepoints tested up to 16 weeks after the prime dose, but achieved similar antibody responses to previously infected participants by 4 weeks after the second dose. Individuals primed with the BNT162b2 vaccine showed a larger decrease in mean anti-RBD and anti-spike IgG concentrations with a 16-week interval between doses (from 8·12 log BAU/mL to 4·25 log BAU/mL for anti-RBD IgG responses and from 8·18 log BAU/mL to 6·66 log BAU/mL for anti-spike IgG responses) than did those who received the mRNA-1273 vaccine (two doses of mRNA-1273: from 8·06 log BAU/mL to 7·49 log BAU/mL for anti-RBD IgG responses and from 6·82 log BAU/mL to 7·56 log BAU/mL for anti-spike IgG responses; mRNA-1273 followed by BNT162b2: from 8·83 log BAU/mL to 7·95 log BAU/mL for anti-RBD IgG responses and from 8·50 log BAU/mL to 7·97 log BAU/mL for anti-spike IgG responses). No differences in antibody responses 4 weeks after the second dose were noted between the two vaccines, in either homologous or heterologous combinations. INTERPRETATION: Interim results of this ongoing longitudinal study show that among frail, older people, previous SARS-CoV-2 infection and the type of mRNA vaccine influenced antibody responses when used with a 16-week interval between doses. In these cohorts of frail, older individuals with a similar age and comorbidity distribution, we found that serological responses were similar and clinically equivalent between the discovery and confirmatory cohorts. Homologous and heterologous use of mRNA vaccines was not associated with significant differences in antibody responses 4 weeks following the second dose, supporting their interchangeability. FUNDING: Public Health Agency of Canada, Vaccine Surveillance Reference Group; and the COVID-19 Immunity Task Force. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.
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Vacinas contra COVID-19 , COVID-19 , Vacina de mRNA-1273 contra 2019-nCoV , Idoso , Vacina BNT162 , Idoso Fragilizado , Humanos , Imunoglobulina G , Estudos Longitudinais , Estudos Prospectivos , RNA Mensageiro , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vacinação , Vacinas Sintéticas , Vacinas de mRNARESUMO
OBJECTIVE: To investigate whether a simplified inflammation-based risk scoring system comprising three readily available biomarkers (albumin, C-reactive protein, and leukocytes) may predict major adverse outcomes in patients with COVID-19. METHODS: Upon admission to the emergency room, the inflammation-based risk scoring system was applied and patients were classified as having mild, moderate, or severe inflammation. In-hospital occurrence of thrombosis, need for mechanical ventilation, and death were recorded. RESULTS: One-hundred patients (55 ± 13 years; 71% men) were included and classified as having mild (29%), moderate (12%), or severe (59%) inflammation. The need for mechanical ventilation differed among patients in each group (16%, 50%, and 71%, respectively; P < 0.0001), yielding a 4.1-fold increased risk of requiring mechanical ventilation in patients with moderate inflammation and 5.4 for those with severe inflammation. On the contrary, there were no differences for the occurrence of thrombosis (10%, 8%, and 22%, respectively; P = 0.142) or death (21%, 42%, and 39%, respectively; P = 0.106). In the multivariate analysis, only severe inflammation (hazard ratio [HR] = 4.1), D-dimer > 574 ng/mL (HR = 3.0), and troponin I ≥ 6.7 ng/mL (HR = 2.4) at hospital admission were independent predictors of the need for mechanical ventilation. CONCLUSION: The inflammation-based risk scoring system predicts the need for mechanical ventilation in patients with severe COVID-19.
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COVID-19/terapia , Respiração Artificial , SARS-CoV-2 , Índice de Gravidade de Doença , Adulto , Idoso , Biomarcadores/sangue , COVID-19/sangue , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Hospitalização , Humanos , Inflamação/sangue , Inflamação/terapia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Troponina I/sangueRESUMO
An elderly woman admitted in our geriatric inpatient unit suffered from disturbing outbursts of crying and, less frequently, episodes of laughing. The patient was diagnosed with pseudobulbar affect related to a mixed neurodegenerative disorder. This condition is often underdiagnosed and undertreated, despite being relatively frequent in patients with neurodegenerative disorders. This case report describes the treatment of pseudobulbar affect in this patient. The only available treatment in Canada for this condition, antidepressants, was not effective for our patient. Dextromethorphan/quinidine is a good accepted alternative, but the combination is not marketed in Canada. To manage this problem, we used compounded quinidine capsules and dextromethorphan cough syrup. The crying of our patient improved significantly and rapidly after the initiation of this treatment. This case will help professionals to review their central role in treating this complex and disabling condition.
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Objective: Benzodiazepines (BZD) are often prescribed to address sleep difficulties but many BZD users report a poor quality of sleep. Although social support was found to be associated with quality of sleep in a recent meta-analysis, this relationship was never studied in older BZD users. This study thus aims to examine how social support is associated with quality of sleep in older BZD users.Method: Seventy-two older adults (age 60-85) using BZD were recruited. Data was collected during the pre-test of the ''PASSE-60+; Support program for a successful withdrawal, NCT02281175'' study. Quality of sleep was measured using the Pittsburgh Sleep Quality Index (PSQI), while social support was evaluated with the Social Support Questionnaire (SSQ-6).Results: When examining the various dimensions of self-reported sleep quality as a whole, we found no significant association with social support, while controlling for daily BZD dose, anxiety and depression. However, we found a significant association between self-reported diurnal dysfunctions (e.g., daytime sleepiness) and satisfaction with social support.Conclusion: Although the results of our study should be replicated with larger samples, they might indicate that social support is not a significant factor influencing sleep quality in older chronic BZD users. Our results could differ from those found in other populations because of the changes in sleep quality associated with long term BZD use. Longitudinal studies should analyse the relationship between diurnal dysfunctions and satisfaction with social support, to examine if social support could help older adults alleviate their diurnal dysfunctions and eventually facilitate BZD tapering.
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Benzodiazepinas , Distúrbios do Início e da Manutenção do Sono , Idoso , Idoso de 80 Anos ou mais , Transtornos de Ansiedade , Humanos , Sono , Distúrbios do Início e da Manutenção do Sono/induzido quimicamente , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Apoio SocialRESUMO
BACKGROUND: Long-term benzodiazepine (BZD) use among seniors is mostly inappropriate and associated with adverse health outcomes. To prevent these consequences, withdrawal is crucial, yet knowledge is limited about what predicts BZD discontinuation. Until now, most studies have focused on sociodemographic and BZD intake factors as predictors while neglecting psychological factors. This research addresses this issue by studying how the intensity of depressive symptoms, social support satisfaction, self-perceived competence in the ability to withdraw, and overall quality of sleep predict discontinuation in long-term older consumers. METHOD: Seventy-three participants aged 60â¯years and older were enrolled in this study. There were four time measures: before discontinuation (T1), after (T2), 3â¯months after (T3), and 12â¯months after (T4). Data were collected in the "Programme d'Aide du Succès au SEvrage" (PASSE-60+) study. RESULTS: Social support satisfaction predicted discontinuation at T2 and T4. Self-perceived competence in the ability to withdraw and depressive symptoms predicted discontinuation at T4. This later prediction was counterintuitive; higher depressive symptoms at T1 were linked with higher discontinuation success. BZD intake factors (length of use and dose) were good predictors for short term discontinuation. Psychological factors were moderate predictors for short term and good predictors for long term discontinuation. CONCLUSION: Psychological factors are good predictors of discontinuation and are better predictors than BZD intake factors of long-term discontinuation. Discontinuation programs should focus on social support and self-perceived competence to improve their efficacy. Further studies are needed to acquire a more complete picture of the psychological predictors of discontinuation success. ClinicalTrials.gov Identifier: NCT02281175.
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Benzodiazepinas/uso terapêutico , Terapia Cognitivo-Comportamental/métodos , Desprescrições , Depressão , Redução da Medicação/métodos , Autoeficácia , Apoio Social , Idoso , Idoso de 80 Anos ou mais , Ansiedade , Benzodiazepinas/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autogestão , Distúrbios do Início e da Manutenção do Sono , Síndrome de Abstinência a Substâncias/psicologiaRESUMO
A healthful diet and sufficient physical activity (PA) are related to several health outcomes. However, there is a paucity of data on the association of PA and dietary pattern with life satisfaction (LS) in the older adults aged ≥65. The present study investigated the independent and combined association of PA and Baltic Sea diet (BSD) score with LS in older Finnish women. Subjects were 554 women aged 65-72 years from the Osteoporosis Risk Factor and Prevention - Fracture Prevention Study. Women reported the hours and type of PA and lifestyle factors via questionnaires and dietary intake using the 3-d food record. Adequate PA was considered according to WHO recommendation: PA = 0, 0 < PA < 2·5 and ≥2·5 h/week. BSD score was categorised as <13 or ≥13 based on the median score. LS was self-reported using LS scale with four items on current 'interest', 'happiness in life', 'ease of living' and 'feelings of loneliness' (range: 4-20, lower score representing higher satisfaction). After adjusting for the confounders, PA was statistically significantly associated with lower LS score (ß coefficient = -0·207, P = 0·001), where women with PA ≥ 2·5 h/week had the lowest LS score followed by women with 0 < PA < 2·5 and PA = 0 (Pfor trend = 0·020). Association between BSD and LS was NS. Only among women with BSD score ≥ 13, but not BSD < 13, PA ≥ 2·5 h/week was statistically significantly associated with lower LS score (mean = 9·3), followed by 0 < PA < 2·5 (mean = 9·9) and PA = 0 groups (mean = 11·8) (Pfor trend = 0·033). In conclusion, adequate PA according to WHO recommendation independently and in combination with higher BSD score may be associated with higher LS in older women.
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Dieta , Exercício Físico , Satisfação Pessoal , Absorciometria de Fóton , Idoso , Composição Corporal , Densidade Óssea , Densitometria , Feminino , Finlândia , Humanos , Estilo de Vida , Oceanos e Mares , Fraturas por Osteoporose/epidemiologia , Inquéritos e QuestionáriosRESUMO
BACKGROUND: The Sentinel Initiative was established in 2008 to monitor the safety of FDA-regulated medical products. We evaluated the positive predictive value (PPV) of ICD-9 codes for post-vaccination febrile seizures to identify optimal algorithms for use in post-market safety surveillance. METHODS: We identified ICD-9 diagnosis codes for fever and seizures in the emergency department or inpatient setting after vaccinations of interest from July 1, 2010 to June 30, 2011. Medical record review was conducted to verify febrile seizure events. RESULTS: Of 216 potential febrile seizures identified with one or more seizure codes (the broadest algorithm), 152 were chart-confirmed (i.e., documentation of fever within 24â¯h of seizure or clinician diagnosis of febrile seizure; PPV 70%, 95% CI 64, 76%). Two codes specific for febrile seizures produced the highest PPV (PPV 91%, 95% CI 85, 95%) and accounted for 140 confirmed febrile seizures. In the absence of febrile seizure codes, other seizure codes yielded much lower PPVs, regardless of the presence of fever codes. CONCLUSIONS: Our results indicate that ICD-9 diagnosis codes in the inpatient and emergency department settings have high predictive value for identifying febrile seizures within the Sentinel Distributed Database. While the PPV of the algorithm based on any diagnosis code for seizure is moderate, the algorithm limited to febrile seizure codes has a high PPV (>90%) and captures the vast majority of confirmed cases identified by the broadest algorithm, suggesting that the narrower algorithm limited to febrile seizure codes may be preferred.
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Imunização/métodos , Convulsões Febris/prevenção & controle , Vacinação/métodos , Algoritmos , Pré-Escolar , Feminino , Humanos , Programas de Imunização , Lactente , Masculino , Valor Preditivo dos Testes , Convulsões Febris/imunologiaRESUMO
Along with the quick development of flexible and wearable electronic devices, there is an ever-growing demand for light-weight, flexible, and wearable power sources. Because of the high power density, excellent cycling stability and easy fabrication, flexible supercapacitors are widely studied for this purpose. Graphene-based nanomaterials are attractive electrode materials for flexible and wearable supercapacitors owing to their high surface area, good mechanical and electrical properties, and excellent electrochemical stability. The 2D structure and high aspect ratio of graphene nanosheets make them easy to assemble into films or fibers with good mechanical properties. In recent years, enormous progress has been made in developing flexible and wearable graphene-based supercapacitors. Here, the material and structure design strategies for developing film-shaped and emerging fiber-shaped flexible supercapacitors based on graphene nanomaterials are summarized.
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Grafite/química , Nanoestruturas/química , Dispositivos Eletrônicos Vestíveis , Capacitância ElétricaRESUMO
BACKGROUND: Genetic polymorphisms of antioxidant enzymes CAT, GPX, and SOD are involved in the etiology of obesity and its principal comorbidities. The aim of the present study was to analyze the effect of aforementioned SNPs over the output of several variables in people with obesity after a nutritional intervention. The study included 92 Mexican women, which received a dietary intervention by 3 months. Participants were genotyped and stratified into two groups: (1) carriers; mutated homozygous plus heterozygous (CR) and (2) homozygous wild type (WT). A comparison between CR and WT was done in clinical (CV), biochemical (BV), and anthropometric variables (AV), at the beginning and at the end of the intervention. RESULTS: Participants (n = 92) showed statistically significant differences (p < 0.05) at the end of the nutritional intervention in several CV, BV, and AV. However, two kinds of responses were observed after genotyping participants: (A) CR and WT showed statistically significant differences (p < 0.05) in several CV, BV, and AV for the SNPs 599C>T GPX1 (rs1050450), - 251A>G SOD1 (rs2070424), and - 262C>T CAT (rs1001179). (B) Only CR showed statistically changes (p < 0.05) in several CV, BV, and AV for the SNPs - 21A>T CAT (rs7943316) and 47C>T SOD2 (rs4880). The dietary intervention effect was statistically significantly between the polymorphisms of 47C>T SOD2 and BMI, SBP, TBARS, total cholesterol, and C-LCL (p < 0.05) and between the polymorphisms of - 21A>T CAT (rs7943316) and SBP, DBP, total cholesterol, and atherogenic index (p < 0.05). CONCLUSION: People with obesity display different response in several CV, BV, and AV after a nutritional intervention, depending on the antioxidant genetic background of SOD and CAT enzymes.
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OBJECTIVE: A relationship between generalized anxiety disorder (GAD) and fear of falling (FOF) has long been proposed but never specifically studied. This study aimed at analyzing the relationship between FOF and GAD or anxiety symptoms, while controlling for major depressive episodes (MDE), depressive symptoms, fall risk, and sociodemographic variables. METHODS: Twenty-five older adults participated in this pilot study. Assessments included the following: Anxiety Disorder Interview Schedule, Geriatric Anxiety Inventory, Geriatric Depression Scale, Falls-Efficacy Scale-International. A multidisciplinary team evaluated fall risk. RESULTS: FOF was significantly correlated with GAD, MDE, anxiety and depressive symptoms, and fall risk, but not with sociodemographic variables. Multiple regression analyses indicated that GAD and anxiety symptoms were significantly and independently associated with FOF. CONCLUSION: Although the results of this pilot study should be replicated with larger samples, they suggest that FOF is associated with GAD and anxiety symptoms even when considering physical factors that increase the risk of falling. CLINICAL IMPLICATIONS: Treatment of FOF in patients with GAD may present a particular challenge because of the central role of intolerance of uncertainty, which may prevent patients from regaining confidence despite the reduction of fall risk. Clinicians should screen for GAD and anxiety symptoms in patients with FOF to improve detection and treatment.
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Acidentes por Quedas , Transtornos de Ansiedade/psicologia , Ansiedade/psicologia , Medo/psicologia , Avaliação Geriátrica/estatística & dados numéricos , Idoso , Ansiedade/complicações , Transtornos de Ansiedade/complicações , Canadá/epidemiologia , Feminino , Avaliação Geriátrica/métodos , Humanos , Masculino , Projetos Piloto , Fatores de RiscoRESUMO
Objetivo: Analizar la relación entre el uso de los smartphones y las relaciones interpersonales de estudiantes universitarios en la ciudad de Barranquilla. Materiales y métodos: Estudio descriptivo transversal mediante encuesta anónima a 400 estudiantes en una universidad privada, seleccionados aleatoriamente. Variables estudiadas: frecuencia de revisión de mensajes y llamadas, conflicto en las relaciones con padres, amigos y pareja y el distanciamiento en las relaciones generado por el uso de excesivo del móvil. El conflicto en las relaciones se relacionó con las variables sociodemográficas y el perfil de uso de los smartphones. Resultados: El 80 % estaba suscrito a un plan de datos; el 53 % revisaba su smartphone cada 15 minutos o menos; el 66 % lo lleva a todas partes y el 52 % lo usaba en exceso. Las dos razones de uso más frecuentes fueron: mantenerse en contacto/diversión (22 %) y mantenerse en contacto/estudio (12.5 %). Las mujeres usaban más el celular y tenían más conflictos en sus relaciones que los hombres debido al uso excesivo; además, se sentían más molestas/ desplazadas cuando su interlocutor usaba el móvil en su presencia. La principal razón de conflictos por el uso del smartphone en la relación con otras personas fue la distracción. Conclusiones: En general los usuarios consideran que los smartphones afectan positivamente sus relaciones, aunque se presentan conflictos. Hay diferencias por sexo con respecto a la presentación de conflictos por el uso excesivo del móvil, predominante en las mujeres, quienes tienden a tolerar menos que este sea utilizado en su presencia.
Objective: To analyze the relation between the use of smartphones and interpersonal relationships among students at a private university located in city Barranquilla. Materials and methods: A cross sectional study was conducted among 400 randomly selected students. Data was collected regarding frequency of checking income mails and calls, conflict and impact on relationships with parents, partners and peers due to the use of smartphone. Both univariate and bivariate analysis was performed. Association of conflict with other variables regarding smartphone usage pattern and socio-demographic characteristics of users was estimated through odds ratios (OR). Statistical significance was tested by the Chi-square. Results: 80 % of the population subscribed to smartphone services, 53 % checked their smartphones every 15 minutes or less and 51 % reported an excessive use. It was observed that women have more conflicts and negative impacts on their relationships due to the excessive use of their smartphones; likewise they tend to feel more uncomfortable when other people use mobiles around, mainly because smart phone use drives attention away from conversation Conclusions: In general, students find smartphones to influence their relationships with others positively, despite some conflicts that may emerge. Conflicts with others showed to be sex related. Although women's use smartphones is more excessive than those of men, they become displeased when are others who use their mobile phones at their presence.
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An effort to develop smaller, well-dispersed catalytic materials electrochemically on high-surface-area carbon supports is required for improved fuel cell performance. A high-surface-area carbon material of interest is carbon nano-onions (CNOs), also known as multilayer fullerenes. The most convenient synthesis method for CNOs is annealing nanodiamond particles, thus retaining the size of the precursors and providing the possibility to prepare very small nanocatalysts using electrochemical techniques. In terms of pure metal catalysts, platinum is the most common catalyst used in fuel cells. The combination of Pt nanoparticles with CNOs could lead to new catalytic nanomaterials. In this work, this was accomplished by using a rotating disk-slurry electrode (RoDSE) technique. The Pt/CNO catalysts were prepared from slurries that contained functionalized CNOs and K(2)PtCl(6) as the platinum precursor in aqueous 0.1 M H(2)SO(4) solution. X-ray photoelectron spectroscopy results showed that 37% of the Pt on the CNOs is metallic Pt whereas 63% had higher binding energies, which is evidence of higher oxidation states or the presence of Pt atoms and clusters on CNOs. However, aberration-corrected scanning transmission electron microscopy of the Pt/CNOs confirmed the presence of Pt atoms and clusters on CNOs. Thermal gravimetric analysis showed the excellent thermal stability of the Pt/CNOs and a lower onset potential for the electrochemical oxidation of methanol compared to that of commercial Pt/Vulcan catalyst material. The computational method confirmed the Pt atoms' location at CNOs surface sites. Geometric parameters for distances between Pt atoms in the 3Pt/CNOs molecular system from our theoretical calculations are in agreement with the respective parameters obtained experimentally. The combination of CNO with RoDSE presents a new highly dispersed catalyst nanomaterial.
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Fulerenos/química , Nanoestruturas/química , Platina/química , Catálise , Eletrodos , Galvanoplastia , Metanol/química , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Nanoestruturas/ultraestrutura , Oxirredução , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Propriedades de Superfície , TermodinâmicaRESUMO
This paper reports the decoration of single wall carbon nanotubes (SWCNTs) with platinum (Pt) nanoparticles using an electrochemical technique, rotating disk slurry electrode (RoDSE). Pt/SWCNTs were electrochemically characterized by cyclic voltammetry technique (CV) and physically characterized through the use of transmission electron microscopy (TEM), energy dispersive spectroscopy - X-ray florescence (EDS-XRF) and X-ray diffraction (XRD). After characterization it was found that electrodeposited nanoparticles had an average particle size of 4.1 ± 0.8 nm. Pt/SWCNTs were used as sensing material for methane (CH4) detection and showed improved sensing properties in a range of concentration from 50 ppm to 200 ppm parts per million (ppm) at room temperature, when compared to other Pt/CNTs-based sensors. The use of this technique for the preparation of Pt/SWCNTs opens a new possibility in the bulk preparation of samples using an electrochemical method and thus their potential use in a wide variety of applications in chemical sensing, fuel cell and others.
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PURPOSE: The expression of S- and M-opsins in the murine retina is altered in different transgenic mouse models with mutations in the thyroid hormone receptor (TR)-beta gene, demonstrating an important role of thyroid hormone (TH) in retinal development. METHODS: The spatial expression of S- and M-opsin was compared in congenital hypothyroidism and in two different TR mutant mouse models. One mouse model contains a ligand-binding mutation that abolishes TH binding and results in constitutive binding to nuclear corepressors. The second model contains a mutation that blocks binding of coactivators to the AF-2 domain without affecting TH binding. RESULTS: Hypothyroid newborn mice showed an increase in S-opsin expression that was completely independent of the genotype. Concerning M-opsin expression, hypothyroidism caused a significant decrease (P < 0.01) only in wild-type animals. When TRbeta1 and -beta2 were T3-binding defective, the pattern of opsin expression was similar to TRbeta ablation, showing increased S-opsin expression in the dorsal retina and no expression of M-opsin in the entire retina. In an unexpected finding, immunostaining for both opsins was detected when both subtypes of TRbeta were mutated in the helix 12 AF-2 domain. CONCLUSIONS: The results show, for the first time, that the expression of S- and M-opsin is dependent on normal thyroid hormone levels during development.