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1.
JAMA ; 331(20): 1722-1731, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38696203

RESUMO

Importance: Most people who smoke do not quit on their initial attempt. Objective: To determine the best subsequent strategy for nonabstinence following initial treatment with varenicline or combined nicotine replacement therapy (CNRT). Design, Setting, and Participants: Using a double-blind, placebo-controlled, sequential multiple assignment randomized trial, 490 volunteers were randomized to receive 6 weeks of varenicline or CNRT. After 6 weeks, nonabstainers were rerandomized to continue, switch, or increase medication dosage for 6 additional weeks. The study was conducted from June 2015 through October 2019 in a Texas tobacco treatment clinic. Interventions: The initial treatment was 2 mg/d of varenicline or the combined replacement therapy of a 21-mg patch plus 2-mg lozenge. The rerandomized participants either continued with their initial therapies, switched between varenicline and CNRT, or increased dosages either to 3-mg or more of varenicline or to a 42-mg patch and lozenges. All received weekly brief counseling. Main Outcomes and Measures: Biochemically verified 7-day point prevalence abstinence at the end of treatment at 12 weeks. Results: The 490 randomized participants (210 female [43%], 287 non-Hispanic White [58%], mean age, 48.1 years) smoked an average of 20 cigarettes per day. After the first phase, 54 participants in the CNRT group were abstinent and continued their therapy; of the 191 who were not abstinent, 151 were rerandomized, and the 40 who did not return for rerandomization were assigned to continue their initial CNRT condition in phase 2. The end-of-treatment abstinence rate for the 191 phase 1 nonabstainers was 8% (95% credible interval [CrI], 6% to 10%) for the 90 (47%) who continued at the dosage condition, 14% (CrI, 10% to 18%) for the 50 (33%) who increased their dosage, and 14% (95% CrI, 10% to 18%) for the 51 (34%) who switched to varenicline (absolute risk difference [RD], 6%; 95% CrI, 6% to 11%) with more than 99% posterior probability that either strategy conferred benefit over continuing the initial dosage. After the first phase, 88 participants in the varenicline group were abstinent and continued their therapy; of the 157 who were not abstinent, 122 were rerandomized and 35 who did not return for rerandomization were assigned to continue with the varenicline condition. The end-of-treatment abstinence rate for the 157 phase 1 nonabstainers was 20% (95% CrI, 16% to 26%) for the 39 (32%) who increased their varenicline dosage, 0 (95% CrI, 0 to 0) for the 41 (34%) who switched CNRT, and 3% (95% CrI, 1% to 4%) for the 77 (49%) who were assigned to the continued varenicline condition (absolute RD, -3%; 95% CrI, -4% to -1%) with more than 99% posterior probability that continuing varenicline at the initial dosage was worse than switching to a higher dosage. Furthermore, increasing the varenicline dosage had an absolute RD of 18% (95% CrI, 13% to 24%) and a more than 99% posterior probability of conferring benefit. The secondary outcome of continuous abstinence at 6 months indicated that only increased dosages of the CNRT and varenicline provided benefit over continuation of the initial treatment dosages. Conclusions and Relevance: For individuals who smoked but did not achieve abstinence after treatment with varenicline, increasing the dosage enhanced abstinence vs continuing, whereas for nonabstainers initially treated with CNRT, a dosage increase or switch to varenicline enhanced abstinence and may be viable rescue strategies. Trial Registration: ClinicalTrials.gov Identifier: NCT02271919.


Assuntos
Nicotina , Agonistas Nicotínicos , Agentes de Cessação do Hábito de Fumar , Abandono do Hábito de Fumar , Vareniclina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Duplo-Cego , Nicotina/administração & dosagem , Nicotina/efeitos adversos , Nicotina/uso terapêutico , Agonistas Nicotínicos/administração & dosagem , Agonistas Nicotínicos/uso terapêutico , Abandono do Hábito de Fumar/métodos , Agentes de Cessação do Hábito de Fumar/uso terapêutico , Agentes de Cessação do Hábito de Fumar/efeitos adversos , Agentes de Cessação do Hábito de Fumar/administração & dosagem , Falha de Tratamento , Vareniclina/uso terapêutico , Vareniclina/administração & dosagem , Vareniclina/efeitos adversos , Brancos
2.
Support Care Cancer ; 30(5): 4485-4495, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35112209

RESUMO

PURPOSE: In efforts to understand financial distress (FD) associated with advanced cancer care from the perspective of both patients with incurable disease and their spousal caregivers, we assessed FD in both members of the couple, identified symptom and quality of life (QOL) correlates, and examined the potential role of illness communication. METHODS: Patients undergoing treatment for stage III/IV lung cancer or a grade III/IV primary brain tumor and their spousal caregivers (n = 76 dyads) completed measures of somatic and affective symptoms including FD, physical and mental QOL, and ease of engaging in illness communication. Patients and caregivers additionally rated their perception of each other's symptoms, including FD. RESULTS: FD was endorsed by both patients (any FD 62.7%; high FD 24%) and spousal caregivers (any FD 64.7%; high FD 32.3%). Self-reported FD was significantly correlated (partial r = .52, p < .001) within couples. FD was associated with greater symptoms of anxiety (r = .29, p = .01; r = .31, p = .01), depression (r = 29, p = 01; r = .39, p = .001), and poorer physical QOL(r = - .25, p = .03; r = - .25, p = .001) for patients and caregivers, respectively. For patients, FD was additionally associated with poorer mental QOL(r = - .44, p < .001). Caregivers accurately perceived patient FD, yet patients tended to underreport their caregiver's FD by almost an entire point (t = 2.8, p = .007). A 3-way interaction (FD X role X illness communication) revealed (b = .40, p = .041) that illness communication moderated the association between FD and physical QOL for spouses so that spouses who reported less ease of illness communication demonstrated a stronger association between financial distress and physical QOL (b = - 2.08, p < .001) than those reporting greater ease of engaging in illness communication (b = .49, p = .508). CONCLUSION: In the advanced cancer setting, FD is prevalent in both patients and their spousal caregivers and associated with psychological distress and poor physical QOL. Results suggest that optimal FD assessment should include patients and spouses, and spouse's ease of engaging with illness communication may be a potential target for future intervention studies.


Assuntos
Neoplasias Pulmonares , Qualidade de Vida , Adaptação Psicológica , Cuidadores/psicologia , Humanos , Qualidade de Vida/psicologia , Cônjuges/psicologia
3.
Molecules ; 27(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36557797

RESUMO

Recently, a novel electrochemical regulation associated with a deposition/dissolution reaction on an electrode surface has been proven to show superiority in large-scale energy storage systems (ESSs). Hence, in the search for high-performance electrodes showcasing these novel regulations, we utilized a low-cost ZnO microsphere electrode to construct aqueous rechargeable batteries (ARBs) that supplied a harvestable and storable charge through electrochemical deposition/dissolution via a reversible manganese oxidation reaction (MOR)/manganese reduction reaction (MRR), respectively, induced by the inherent formation/dissolution of zinc basic sulfate in a mild aqueous electrolyte solution containing 2 M ZnSO4 and 0.2 M MnSO4.

4.
Nano Lett ; 18(4): 2402-2410, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29570307

RESUMO

Owing to their safety and low cost, aqueous rechargeable Zn-ion batteries (ARZIBs) are currently more feasible for grid-scale applications, as compared to their alkali counterparts such as lithium- and sodium-ion batteries (LIBs and SIBs), for both aqueous and nonaqueous systems. However, the materials used in ARZIBs have a poor rate capability and inadequate cycle lifespan, serving as a major handicap for long-term storage applications. Here, we report vanadium-based Na2V6O16·3H2O nanorods employed as a positive electrode for ARZIBs, which display superior electrochemical Zn storage properties. A reversible Zn2+-ion (de)intercalation reaction describing the storage mechanism is revealed using the in situ synchrotron X-ray diffraction technique. This cathode material delivers a very high rate capability and high capacity retention of more than 80% over 1000 cycles, at a current rate of 40C (1C = 361 mA g-1). The battery offers a specific energy of 90 W h kg-1 at a specific power of 15.8 KW kg-1, enlightening the material advantages for an eco-friendly atmosphere.

5.
J Nanosci Nanotechnol ; 18(10): 7115-7119, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29954543

RESUMO

This study investigated the effect of synthesis time and composition on magnetic properties of FeCo nanoparticles. Fe75Co25, Fe66Co34, Fe52Co48 nanoparticles were synthesized by the polyol method. The saturation magnetization of Fe75 Co25, Fe66Co34, Fe52Co48 nanoparticles was 178 emu/g, 191 emu/g and 197 emu/g, respectively. The coercivity of Fe75 Co25, Fe66Co34, Fe52Co48 was 113 Oe, 131 Oe and 89.2 Oe respectively. The synthesis time of Fe52Co48 nanoparticles was also varied (2 h and 3 h) to determine the optimal synthesis time. The saturation magnetization of Fe52Co48 synthesized for 2 h, 3 h was 243 emu/g, 202 emu/g, respectively. The coercivity of Fe52Co48 synthesized for 2 h and 3 h was 46 Oe and 111 Oe, respectively. The highest saturation magnetization and lowest coercivity was obtained using a synthesis time of 2 h. Based on these results, it was confirmed that Fe52Co48 had the highest saturation magnetization and lowest coercivity among all of the compositions tested, and optimal synthesis time was 2 h.

6.
Exp Brain Res ; 234(9): 2731-43, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27220768

RESUMO

Experimental evidence is given that the perceptual system adapts to repetitive task execution in a perceptual two-choice judgment task. Participants were tested with respect to their perception of opportunities for plank grasping. Participants had to report whether planks were perceived as objects being graspable with either one hand or two hands. When the plank size was gradually increased and subsequently decreased, transitions from one hand judgments to two hands judgments and vice versa were observed. Analysis of the transition scores revealed that the perceptual judgments were body-scaled, as it is known in the literature. However, judgments were also found to be context dependent. Judgment transition scores were affected in a systematic way by the kind of and the number of previously made judgments. The latter quantitative impact was observed in three related experiments and suggests that perceptual judgments about opportunities for action adapt to task repetition. Overall, the experimental findings are consistent with the predictions of a dynamical systems model, which assumes that perceptual judgments are emergent properties of a self-organizing process that involves inhibitory top-down feedback.


Assuntos
Adaptação Fisiológica/fisiologia , Força da Mão/fisiologia , Julgamento/fisiologia , Desempenho Psicomotor/fisiologia , Percepção de Tamanho/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Feminino , Mãos/fisiologia , Humanos , Masculino , Adulto Jovem
7.
Am J Hypertens ; 37(7): 531-539, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38501167

RESUMO

BACKGROUND: While renin-angiotensin system (RAS) inhibitors have a longstanding history in blood pressure control, their suitability as first-line in-patient treatment may be limited due to prolonged half-life and kidney failure concerns. METHODS: Using a cohort design, we assessed the impact of RAS inhibitors, either alone or in combination with beta-blockers, on mortality, while exploring interactions, including those related to end-stage renal disease and serum creatinine levels. Eligible subjects were Acute Ischemic Stroke (AIS) patients aged 18 or older with specific subtypes who received in-patient antihypertensive treatment. The primary outcome was mortality rates. Statistical analyses included cross-sectional and longitudinal approaches, employing generalized linear models, G-computation, and discrete-time survival analysis over a 20-day follow-up period. RESULTS: In our study of 3,058 AIS patients, those using RAS inhibitors had significantly lower in-hospital mortality (2.2%) compared to non-users (12.1%), resulting in a relative risk (RR) of 0.18 (95% CI: 0.12-0.26). Further analysis using G-computation revealed a marked reduction in mortality risk associated with RAS inhibitors (0.0281 vs. 0.0913, risk difference [RD] of 6.31% or 0.0631, 95% CI: 0.046-0.079). Subgroup analysis demonstrated notable benefits, with individuals having creatinine levels below and above 1.3 mg/dl exhibiting statistically significant RD (RD -0.0510 vs. -0.0895), and a significant difference in paired comparison (-0.0385 or 3.85%, CI 0.023-0.054). Additionally, longitudinal analysis confirmed a consistent daily reduction of 0.93% in mortality risk associated with the intake of RAS inhibitors. CONCLUSIONS: RAS inhibitors are associated with a significant reduction in in-hospital mortality in AIS patients, suggesting potential clinical benefits in improving patient outcomes.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Mortalidade Hospitalar , AVC Isquêmico , Sistema Renina-Angiotensina , Humanos , Masculino , Feminino , Sistema Renina-Angiotensina/efeitos dos fármacos , Idoso , AVC Isquêmico/mortalidade , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/sangue , AVC Isquêmico/diagnóstico , Pessoa de Meia-Idade , Estudos Longitudinais , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Resultado do Tratamento , Anti-Hipertensivos/uso terapêutico , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso de 80 Anos ou mais , Fatores de Risco , Fatores de Tempo , Quimioterapia Combinada , Hipertensão/tratamento farmacológico , Hipertensão/mortalidade , Hipertensão/fisiopatologia , Estudos Transversais , Pressão Sanguínea/efeitos dos fármacos , Antagonistas de Receptores de Angiotensina/uso terapêutico , Medição de Risco
8.
JMIR Res Protoc ; 13: e53307, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652520

RESUMO

BACKGROUND: Cancer is a life-threatening, stressful event, particularly for young adults due to delays and disruptions in their developmental transitions. Cancer treatment can also cause adverse long-term effects, chronic conditions, psychological issues, and decreased quality of life (QoL) among young adults. Despite numerous health benefits of health behaviors (eg, physical activity, healthy eating, no smoking, no alcohol use, and quality sleep), young adult cancer survivors report poor health behavior profiles. Determining the associations of stress (either cancer-specific or day-to-day stress), health behaviors, and QoL as young adult survivors transition to survivorship is key to understanding and enhancing these survivors' health. It is also crucial to note that the effects of stress on health behaviors and QoL may manifest on a shorter time scale (eg, daily within-person level). Moreover, given that stress spills over into romantic relationships, it is important to identify the role of spouses or partners (hereafter partners) in these survivors' health behaviors and QoL. OBJECTIVE: This study aims to investigate associations between stress, health behaviors, and QoL at both within- and between-person levels during the transition to survivorship in young adult cancer survivors and their partners, to identify the extent to which young adult survivors' and their partners' stress facilitates or hinders their own and each other's health behaviors and QoL. METHODS: We aim to enroll 150 young adults (aged 25-39 years at the time of cancer diagnosis) who have recently completed cancer treatment, along with their partners. We will conduct a prospective longitudinal study using a measurement burst design. Participants (ie, survivors and their partners) will complete a daily web-based survey for 7 consecutive days (a "burst") 9 times over 2 years, with the bursts spaced 3 months apart. Participants will self-report their stress, health behaviors, and QoL. Additionally, participants will be asked to wear an accelerometer to assess their physical activity and sleep during the burst period. Finally, dietary intake (24-hour diet recalls) will be assessed during each burst via telephone by research staff. RESULTS: Participant enrollment began in January 2022. Recruitment and data collection are expected to conclude by December 2024 and December 2026, respectively. CONCLUSIONS: To the best of our knowledge, this will be the first study that determines the interdependence of health behaviors and QoL of young adult cancer survivors and their partners at both within- and between-person levels. This study is unique in its focus on the transition to cancer survivorship and its use of a measurement burst design. Results will guide the creation of a developmentally appropriate dyadic psychosocial or behavioral intervention that improves both young adult survivors' and their partners' health behaviors and QoL and potentially their physical health. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53307.


Assuntos
Sobreviventes de Câncer , Comportamentos Relacionados com a Saúde , Qualidade de Vida , Estresse Psicológico , Adulto , Feminino , Humanos , Masculino , Sobreviventes de Câncer/psicologia , Qualidade de Vida/psicologia , Cônjuges/psicologia , Estresse Psicológico/psicologia , Inquéritos e Questionários , Sobrevivência , Projetos de Pesquisa
9.
Psychol Addict Behav ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37747518

RESUMO

OBJECTIVE: The timeline follow-back interview is a common method of collecting daily cigarette consumption (cigarettes per day [CPD]) in smoking research. However, it may be subject to recall bias due to its reliance on retrospective reports. The increasing ownership of smartphones allows researchers to administer app-based digital diaries (DD) to collect CPD, which is expected to have less recall bias. Several studies have compared these two methods and found a noticeable discrepancy between them. However, these studies have mainly focused on the time window when smokers were smoking ad libitum. In this study, we wanted to determine the comparability of these two methods when treatment-seeking smokers are attempting to quit smoking. METHOD: In a cessation trial, treatment-seeking smokers (n = 251) reported their CPD using the timeline follow-back and DD methods over a 12-week treatment period. To evaluate the comparability, we used the Bland-Altman comparison approach for agreement, correlational analysis between CPD and biochemical measures, digit bias, and logistic regression for predicting abstinence. RESULTS: We found that the two methods exhibited good agreement, and the agreement did not vary as a function of consumption levels. Consistent with this agreement, CPD data from both methods showed similar correlations with biochemical measures of smoking and predicted 6-month abstinence in a comparable fashion. Despite the agreement, the DD method appeared to be more precise by having a lower digit bias than the timeline follow-back method. CONCLUSIONS: Capturing smoking behavior using either TLFB or DD approaches yields similar data while smokers are attempting to quit smoking. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

10.
Artigo em Inglês | MEDLINE | ID: mdl-37940143

RESUMO

Continuous tobacco use in cancer patients is linked to substantial healthcare costs due to increased risks and complications, whereas quitting smoking leads to improved treatment outcomes and cost reductions. Addressing the need for empirical evidence on the economic impact of smoking cessation, this study examined the association between smoking cessation and healthcare cost utilization among a sample of 930 cancer patients treated at The University of Texas MD Anderson Cancer Center's Tobacco Research and Treatment Program (TRTP). Applying conditional quantile regression and propensity scores to address confounding, our findings revealed that abstinence achieved through the TRTP significantly reduced the median cost during a 3-month period post-quitting by $1,095 (ß=-$1,095, p=0.007, 95%CI=[-$1,886, -$304]). Sensitivity analysis corroborated these conclusions, showing a pronounced cost reduction when outlier data were excluded. The long-term accrued cost savings from smoking cessation could potentially offset the cost of participation in the TRTP program, underscoring its cost-effectiveness. An important implication of this study is that by reducing smoking rates, healthcare systems can more efficiently allocate resources, enhance patient health outcomes, and lessen the overall cancer burden.

11.
Cancers (Basel) ; 14(6)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35326615

RESUMO

BACKGROUND: Smoking negatively affects overall survival after successful breast cancer (BC) treatment. We hypothesized that smoking cessation would improve survival outcomes of BC patients who were smokers at the time of diagnosis. METHODS: This was a retrospective analysis of self-identified smokers with BC treated at The University of Texas MD Anderson Cancer Center. Patient demographics, date of diagnosis, tumor stage, tobacco treatment program (TP) participation, and time to death were extracted from our departmental databases and institutional electronic health records. We examined associations between tobacco abstinence status and survival using survival models, with and without interactions, adjusted for personal characteristics and biomarkers of disease. RESULTS: Among all 31,069 BC patients treated at MD Anderson between 2006 and 2017, we identified 2126 smokers (6.8%). From those 2126 self-identified smokers, 665 participated in the TP, reporting a conservative estimate of 31% abstinence (intent-to-treat) 9 months into the program. Patients without reported follow-up abstinence status (including TP and non-TP participants) were handled in the analyses as smokers. Survival analysis controlled for multiple factors, including disease characteristics and participation in the TP, indicated that abstainers were more likely to be alive with no evidence of disease compared to non-abstainers (HR, 0.593; 95% CI, 0.386-0.911; p = 0.017). CONCLUSION: Our results suggest that quitting smoking is associated with improved survival among BC patients who were smokers at time of diagnosis across all tumor stages. Comprehensive approaches for smoking cessation in patients diagnosed with BC may prolong survival when started as early as the time of diagnosis.

12.
J Pain Symptom Manage ; 61(5): 898-908.e1, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33039605

RESUMO

CONTEXT: Patients with metastatic lung cancer and their spousal caregivers are at high risk of psychological symptoms. Mindfulness may improve psychological symptoms via spiritual well-being (SW); yet, this mediation model has not been examined in a dyadic context. OBJECTIVES: We examined the mediating role of two dimensions of SW (meaning/peace and faith) in the mindfulness-symptoms link in Stage IV lung cancer patients and their spousal caregivers. METHODS: We examined the actor-partner interdependence model of mediation using multivariate multilevel modeling with 78 couples. Four actor-partner interdependence model of mediation analyses were conducted to examine one predictor (mindfulness) × two mediators (meaning/peace and faith) × two psychological symptoms (depressive symptoms and cancer distress). We also tested four alternative models in which mindfulness mediates the associations between SW and psychological symptoms. RESULTS: The alternative model (SW → mindfulness → psychological symptoms) was preferred than the original model (mindfulness → SW → psychological symptoms). For patients, meaning/peace was directly associated with their own psychological symptoms, whereas faith was only indirectly associated with their own psychological symptoms via mindfulness. For spouses, meaning/peace was both directly and indirectly associated with their own psychological symptoms, whereas faith was only directly associated with their own depressive symptoms (but not cancer distress). Moreover, spouses' faith was indirectly associated with patients' psychological symptoms through patients' mindfulness. CONCLUSION: SW is associated with patients' and spouses' psychological symptoms both directly and indirectly through mindfulness. Thus, interventions that target SW, particularly meaning and peace, along with mindfulness may be beneficial to the psychological management of patients facing a terminal disease and their spousal caregivers.


Assuntos
Neoplasias Pulmonares , Atenção Plena , Adaptação Psicológica , Cuidadores , Humanos , Neoplasias Pulmonares/terapia , Qualidade de Vida , Espiritualidade , Cônjuges
13.
Nanomaterials (Basel) ; 11(8)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34443735

RESUMO

Aqueous rechargeable zinc ion batteries (ARZIBs) have gained wide interest in recent years as prospective high power and high energy devices to meet the ever-rising commercial needs for large-scale eco-friendly energy storage applications. The advancement in the development of electrodes, especially cathodes for ARZIB, is faced with hurdles related to the shortage of host materials that support divalent zinc storage. Even the existing materials, mostly based on transition metal compounds, have limitations of poor electrochemical stability, low specific capacity, and hence apparently low specific energies. Herein, NH4V4O10 (NHVO), a layered oxide electrode material with a uniquely mixed morphology of plate and belt-like particles is synthesized by a microwave method utilizing a short reaction time (~0.5 h) for use as a high energy cathode for ARZIB applications. The remarkable electrochemical reversibility of Zn2+/H+ intercalation in this layered electrode contributes to impressive specific capacity (417 mAh g-1 at 0.25 A g-1) and high rate performance (170 mAh g-1 at 6.4 A g-1) with almost 100% Coulombic efficiencies. Further, a very high specific energy of 306 Wh Kg-1 at a specific power of 72 W Kg-1 was achieved by the ARZIB using the present NHVO cathode. The present study thus facilitates the opportunity for developing high energy ARZIB electrodes even under short reaction time to explore potential materials for safe and sustainable green energy storage devices.

14.
ACS Appl Mater Interfaces ; 13(4): 5602-5613, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33496182

RESUMO

Respiration monitoring and human sweat sensing have promising application prospects in personal healthcare data collection, disease diagnostics, and the effective prevention of human-to-human transmission of fatal viruses. Here, we have introduced a unique respiration monitoring and touchless sensing system based on a CsPb2Br5/BaTiO3 humidity-sensing layer operated by water-induced interfacial polarization and prepared using a facile aerosol deposition process. Based on the relationship between sensing ability and layer thickness, the sensing device with a 1.0 µm thick layer was found to exhibit optimal sensing performance, a result of its ideal microstructure. This sensor also exhibits the highest electrical signal variation at 0.5 kHz due to a substantial polarizability difference between high and low humidity. As a result, the CsPb2Br5/BaTiO3 sensing device shows the best signal variation of all types of breath-monitoring devices reported to date when used to monitor sudden changes in respiratory rates in diverse situations. Furthermore, the sensor can effectively detect sweat evaporation when placed 1 cm from the skin, including subtle changes in capacitance caused by finger area and motion, skin moisture, and contact time. This ultrasensitive sensor, with its fast response, provides a potential new sensing platform for the long-term daily monitoring of respiration and sweat evaporation.


Assuntos
Compostos de Bário/química , Técnicas Biossensoriais/instrumentação , Compostos de Bromo/química , Respiração , Suor/química , Titânio/química , Testes Respiratórios/instrumentação , Césio/química , Desenho de Equipamento , Humanos , Umidade , Chumbo/química , Monitorização Fisiológica/instrumentação , Nanocompostos/química
15.
Adv Sci (Weinh) ; 8(4): 2002636, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33643793

RESUMO

Manganese (Mn)-based cathode materials have garnered huge research interest for rechargeable aqueous zinc-ion batteries (AZIBs) due to the abundance and low cost of manganese and the plentiful advantages of manganese oxides including their different structures, wide range of phases, and various stoichiometries. A novel in situ generated Mn-deficient ZnMn2O4@C (Mn-d-ZMO@C) nanoarchitecture cathode material from self-assembly of ZnO-MnO@C for rechargeable AZIBs is reported. Analytical techniques confirm the porous and crystalline structure of ZnO-MnO@C and the in situ growth of Mn deficient ZnMn2O4@C. The Zn/Mn-d-ZMO@C cell displays a promising capacity of 194 mAh g-1 at a current density of 100 mA g-1 with 84% of capacity retained after 2000 cycles (at 3000 mA g-1 rate). The improved performance of this cathode originates from in situ orientation, porosity, and carbon coating. Additionally, first-principles calculations confirm the high electronic conductivity of Mn-d-ZMO@C cathode. Importantly, a good capacity retention (86%) is obtained with a year-old cell (after 150 cycles) at 100 mA g-1 current density. This study, therefore, indicates that the in situ grown Mn-d-ZMO@C nanoarchitecture cathode is a promising material to prepare a durable AZIB.

16.
ACS Appl Mater Interfaces ; 12(14): 16376-16386, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32186369

RESUMO

Lithium-ion batteries (LIBs) are widely used in various electronic devices and have garnered a huge amount of attention. In addition, evaluation of the intrinsic properties of LIB cathode materials is of considerable interest for practical applications. Therefore, through first-principles calculations based on the density functional theory, we investigated the structural, electronic, electrochemical, and kinetic properties of mixed transition metals, that is, Ni-substituted LiMnPO4 (LMP) and LiMnPO4F (LMPF) cathode materials, that is, LiMn0.5Ni0.5PO4 (LMNP) and LiMn0.5Ni0.5PO4F (LMNPF), respectively, which have not been extensively studied. We also evaluated their delithiated phases, that is, Mn0.5Ni0.5PO4 (MNP) and Mn0.5Ni0.5PO4F (MNPF). Our calculations suggest that Ni substitution significantly affected the structural and electrochemical properties. After Li insertion, the MNPF unit-cell volume increased by about 8%, lower than that of pristine MnPO4F. The Li intercalation voltage also increased in LMNP (4.27 V) and LMNPF (5.23 V). In addition, the migration barrier was calculated to be 0.4 eV for LMNPF, lower than that of LMPF. This study may provide insights for developing LMNP and LMNPF cathode materials in LIB applications.

17.
Chem Commun (Camb) ; 55(26): 3793-3796, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30864605

RESUMO

We explore NaV6O15 (NVO) nanorod cathodes prepared by a sol-gel method for aqueous rechargeable zinc-ion battery applications for the first time. The NVO cathode delivers a high capacity of 427 mA h g-1 at 50 mA g-1 current density. Furthermore, based on the mass of the active materials, it exhibits a high energy density of 337 W h kg-1.

18.
RSC Adv ; 9(42): 24030-24038, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35527880

RESUMO

A simple one-pot polyol-assisted pyro-technique has been adopted to synthesize highly crystalline, carbon-coated LiMn2O4 (LMO/C) nanoparticles for use as a cathode material in rechargeable Li-ion battery (LIB) applications. The phase purity, structure and stoichiometry of the prepared cathode was confirmed using X-ray techniques that included high-resolution powder X-ray diffraction and X-ray absorption fine structure spectroscopy. Electron microscopy studies established that the synthetic technique facilitated the production of nano-sized LMO particles with uniform carbon coating. The prepared LMO/C cathode demonstrates excellent electrochemical properties (cycling stabilities of 86% and 77.5% and high rate capabilities of 79% and 36% within the potential windows of 3.3-4.3 V and 2.5-4.3 V, respectively). The high electrochemical performance of the LMO/C cathode is attributed to the nano-size of the LiMn2O4 particles enabling high surface area and hence greater lithium insertion and also the uniform amorphous carbon coating facilitating effective reduction in manganese dissolution and volume expansion during the lithium de-intercalation/intercalation reactions. In addition, cyclic voltametry and impedance characterization confirm the reversible Li-intercalation and the role of the solid electrolyte interface layer (SEI) in the stable electrochemical reaction of the LMO/C electrode. Furthermore, this study shows the efficacy of a simple and low-cost pyro-synthetic method to realize high performance nano-sized particle electrodes with uniform carbon coating for useful energy storage applications.

19.
R Soc Open Sci ; 6(4): 181978, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31183129

RESUMO

Reduced graphene oxide (rGO) sheets were synthesized by a modified Hummer's method without additional reducing procedures, such as chemical and thermal treatment, by appropriate drying of graphite oxide under ambient atmosphere. The use of a moderate drying temperature (250°C) led to mesoporous characteristics with enhanced electrochemical activity, as confirmed by electron microscopy and N2 adsorption studies. The dimensions of the sheets ranged from nanometres to micrometres and these sheets were entangled with each other. These morphological features of rGO tend to facilitate the movement of guest ions larger than Li+. Impressive electrochemical properties were achieved with the rGO electrodes using various charge-transfer ions, such as Li+, Na+ and K+, along with high porosity. Notably, the feasibility of this system as the carbonaceous anode material for sodium battery systems is demonstrated. Furthermore, the results also suggest that the high-rate capability of the present rGO electrode can pave the way for improving the full cell characteristics, especially for preventing the potential drop in sodium-ion batteries and potassium-ion batteries, which are expected to replace the lithium-ion battery system.

20.
J Nutr Educ Behav ; 50(9): 856-867, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30146454

RESUMO

OBJECTIVE: The current study aimed to examine the interplay between self-efficacy and perceived availabilities of fruits and vegetables (F&V) and energy-dense, low-nutrient foods and sugary drinks (EDLNF&SD) at home and in the school neighborhoods on adolescents' eating behaviors. DESIGN: The Family Life, Activity, Sun, Health, and Eating study, a cross-sectional, Internet-based survey was analyzed. PARTICIPANTS: Adolescent-parent dyads (n = 1,657). INTERVENTIONS: Self-efficacy for F&V intake and limiting EDLNF&SD consumption, perceived F&V and EDLNF&SD availabilities at home and in the school neighborhood, and F&V intake and EDLNF&SD consumption. ANALYSIS: Multiple regression analyses. RESULTS: Adolescents' self-efficacy and perceived home and school neighborhood availability of F&V and EDLNF&SD had significant main effects on their F&V intake and EDLNF&SD consumption, respectively (all P < .01). The positive effect of self-efficacy on F&V intake was greater when home F&V availability was high (+1 SD; b = .29; P < .001) than when it was low (-1 SD; b = .07; P = .040). The effect of home F&V availability on F&V intake was significant when F&V were not available in the school neighborhood (b = .09; P = .006). CONCLUSIONS AND IMPLICATIONS: Given the central role of home availability, it may be considered a fundamental unit of nutrition intervention for adolescents. Multiple contexts (eg, individual, home, school neighborhood) need to be considered to promote adolescents' eating behaviors.


Assuntos
Dieta/estatística & dados numéricos , Comportamento Alimentar/fisiologia , Frutas , Verduras , Adolescente , Adulto , Bebidas/estatística & dados numéricos , Criança , Estudos Transversais , Inquéritos sobre Dietas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pais , Autoeficácia , Fatores Socioeconômicos , Adulto Jovem
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