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1.
Biomacromolecules ; 21(8): 3176-3185, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32640158

RESUMO

How to control osteochondral differentiation of mesenchymal stem cells at a proper stage is a key issue for articular cartilage regeneration. To solve this problem, injectable scaffolds with different chemical functional groups were designed by introducing one equivalent of α-cyclodextrin (α-CD) carboxylate and α-CD phosphate along poly(ethylene glycol)-poly(l-alanine) (PEG-L-PA) block copolymers. Dynamic light scattering, transmission electron microscopy images, and two-dimensional NMR spectra indicated that the PEG-L-PA block copolymers formed inclusion complexes with α-CD derivatives. Aqueous solutions of PEG-L-PA block copolymers (P), α-CD carboxylate/PEG-L-PA block copolymers (PCC), and α-CD phosphate/PEG-L-PA block copolymers (PCP) underwent sol-to-gel transition as the temperature increased. The storage moduli of P, PCC, and PCP gels ranged from 1000 to 1300 Pa at 37 °C. Tonsil-derived mesenchymal stem cells (TMSCs) were incorporated in situ in the gel during thermogelation of P, PCC, and PCP, which became the three-dimensional cell culture systems with different functional groups. After 21 days of incubation of TMSCs in the P, PCC, and PCP systems, the chondrogenic differentiation biomarker of type II collagen significantly increased in the P system, whereas the osteogenic biomarkers of osteocalcin and runt-related transcription factor 2 significantly increased in the PCP system. Both chondrogenic and osteogenic biomarkers were highly expressed in the PCC system. This study proved that thermogelling inclusion complex systems consisting of PEG-L-PA block copolymers and α-CD derivatives could be an excellent injectable matrix for fine-controlling osteochondral differentiation of mesenchymal stem cells.


Assuntos
Células-Tronco Mesenquimais , Diferenciação Celular , Condrogênese , Peptídeos , Polietilenoglicóis
2.
Biomacromolecules ; 21(1): 143-151, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31559819

RESUMO

A poly(ethylene glycol)-based thermogel can capture an iron ion (Fe3+) through a crown ether-like coordination bond between the oxygen atom and metal ions, thus, providing a sustained Fe3+-releasing system. Poly(ethylene glycol)-l-poly(alanine) thermogel was used in this study. The polypeptide forms a rather robust gel, and the degradation products are a neutral amino acid, which provides cyto-compatible neutral pH environments during the cell culture. During the heat-induced sol-to-gel transition at 37 °C, tonsil-derived mesenchymal stem cells (TMSCs) and iron ions were incorporated, leading to the formation of a three-dimensional matrix toward neuronal differentiation of the incorporated TMSCs. The initial concentration of the iron ions was varied between 0, 15, 30, and 60 mM. About 10% of the loaded iron ions was released over 21 days, which continuously supplied iron ions to the cells. The incorporation of iron ions not only increased the gel modulus at 37 °C from 107 to 680 Pa, but also promoted cell aggregation with a significant secretion of the cell adhesion signal of FAK. Expression of biomarkers related to the neuronal differentiation of TMSCs, including NFM, MAP2, GFAP, NURR1, NSE, and TUBB3, increased 4-35-fold at the mRNA level in the Fe3+-containing system compared to that of the system without Fe3+. Immunofluorescence studies also confirmed pronounced cell aggregation and a significant increase in neuronal biomarkers at the protein level. This study suggests that an iron ion-releasing thermogelling system can be a promising injectable scaffold toward neuronal differentiation of stem cells.


Assuntos
Géis/química , Géis/farmacocinética , Ferro/farmacocinética , Células-Tronco Mesenquimais/efeitos dos fármacos , Neurônios/citologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Criança , Feminino , Quinase 1 de Adesão Focal/genética , Marcadores Genéticos/genética , Temperatura Alta , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Neurônios/fisiologia , Tonsila Palatina/citologia , Peptídeos/química , Peptídeos/farmacocinética , Polietilenoglicóis/química , Temperatura de Transição
3.
Psychooncology ; 29(4): 617-631, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32017297

RESUMO

OBJECTIVES: This systematic review of longitudinal studies, assessing subjective cognitive impairment (SCI) reported by adult cancer patients, aimed to summarize evidence on the impact of chemotherapy on SCI, identify moderators of SCI, and evaluate methodological issues. METHODS: Data accrued from Pubmed, EMBASE, CINAHL, PsychInfo, and the Cochrane library. Inclusion criteria were original studies, an exclusively adult sample, valid and reliable subjective cognitive measures, and at least one baseline data point prior to and another after the initiation of chemotherapy. Data were collected on the sample composition, data-collection time points, outcome measures, statistical analysis, and major findings (ie, longitudinal changes in prevalence, severity, and associated factors). RESULTS: Forty articles published between 2004 and 2019 were retained: 21 examined chemotherapy-treated patients only, and 19 employed control groups. Findings were mixed, with slightly more studies supporting the impact of chemotherapy on SCI. SCI tended to be more prevalent and severe after initiating chemotherapy, compared with patients' own baseline and controls not treated with chemotherapy. Impact appeared to be acute and more likely limited to subsamples. Most studies examining non-breast-cancer samples reported the lack or limited impact of chemotherapy on SCI. The most consistent moderators were depression and fatigue. Methodological issues regarding sampling design, measurement, and statistical analysis were discussed. CONCLUSION: More rigorously designed longitudinal studies would clarify direct and indirect effects of chemotherapy on SCI.


Assuntos
Antineoplásicos/efeitos adversos , Disfunção Cognitiva/induzido quimicamente , Autoavaliação Diagnóstica , Neoplasias/tratamento farmacológico , Humanos , Estudos Longitudinais
4.
J Clin Nurs ; 29(15-16): 2945-2952, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32447787

RESUMO

AIMS AND OBJECTIVES: To evaluate the psychometric quality of two single-item pain-intensity measures: the Numeric Rating Scale (NRS) and the Verbal Rating Scale (VRS). BACKGROUND: Measuring pain intensity is a vital step in initiating symptom management and evaluating the effectiveness of interventions with cancer patients. Single-item pain-intensity measures of the NRS and VRS format have been evaluated to be acceptable for use in clinical practice and research; however, evidence to choose one over the other, as a standardised pain-assessment format, is insufficient. DESIGN: Descriptive correlational study. The study was guided and reported following the STROBE guideline. METHODS: Data accrued at two time points during cancer treatment with a total of 249 patients treated in a Korean University Hospital. Two single-item measures were constructed to assess pain intensity over 1 week. The Brief Pain Inventory (BPI; pain intensity subscale and interference subscale) and the functional assessment of chronic illness therapy-fatigue were the criterion. Convergent and concurrent validity were tested with Pearson's correlations. RESULTS: In the convergent-validity evaluation of the cross-sectional association with the BPI, the NRS showed a much higher level of association than the VRS (0.81 versus 0.61). In convergent validity with a longitudinal association with the BPI, the NRS score change had a much higher level of association (0.61 versus 0.37). In concurrent-validity evaluation, the NRS and VRS showed similar levels of associations with fatigue (-0.48 versus -0.49). Yet, the NRS showed statistically higher levels of correlation with functional limitations than the VRS (0.55 versus 0.42), comparable to the concurrent validity of the BPI. CONCLUSION: The NRS showed higher validity than VRS when assessing overall pain intensity over the past week. RELEVANCE TO CLINICAL NURSING: Pain assessment is a vital role of nurses in caring for patients with cancer. Current study findings support the use of the single-item NRS pain measure to assess global pain intensity over the past week.


Assuntos
Dor do Câncer/enfermagem , Medição da Dor/instrumentação , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/normas , Reprodutibilidade dos Testes
5.
Psychooncology ; 27(8): 1995-2001, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29744963

RESUMO

OBJECTIVE: To identify those experiencing significant self-reported cognitive decline over 2 time points during chemotherapy, examine the risk factors for cognitive decline, and examine differences between those with and without significant decline in functional limitations. METHODS: This secondary analysis used data from 163 cancer patients, collected from a Korean University hospital. Significant decline was determined by 15% or more reduction from baseline in the Functional Assessment of Cancer Therapy-Cognitive Function. Multivariate logistic regression was performed to estimate risk factors. Repeated-measures ANOVA and t tests tested differences in groups with and without cognitive decline in cognitive impairment and functional limitation. RESULTS: About 31% (n = 51) experienced significant cognitive decline. Groups with and without decline significantly differed in cognitive-impairment changes over time (F = 238.49, P < .001) and in functional limitations at follow-up (t test, P < .01). Those experiencing increased fatigue over time (odds = 0.94, P < .05) and those who underwent 2 or more cycles between time 1 and 2 (odds = 2.61; P < .05) had higher risk of significant decline over time during chemotherapy. CONCLUSION: Significant cognitive decline occurred during active chemotherapy; attention to cognitive impairment should be given in the early phase of chemotherapy.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Cognição , Disfunção Cognitiva/induzido quimicamente , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/complicações , Idoso , Antineoplásicos/administração & dosagem , Neoplasias da Mama/complicações , Disfunção Cognitiva/psicologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , República da Coreia , Fatores de Risco , Inquéritos e Questionários
6.
Res Nurs Health ; 39(6): 472-479, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27546692

RESUMO

This study was designed to evaluate the reliability (internal consistency, reproducibility over time, and measurement precision) and validity (factorial, convergent, and concurrent validity) of the 4-item Korean Perceived Stress Scale in comparison to the 10-item Korean Perceived Stress Scale. Participants were 650 students from seven schools of nursing in South Korea. Measures included Korean versions of the Perceived Stress Scale, the Pittsburgh Sleep Quality Index, and a single-item quality-of-life measure. The 4-item Perceived Stress Scale had lower Cronbach alpha than the 10-item Perceived Stress Scale (.65 vs. .80), but its item-total correlations (.35-.47) and split-half coefficient (.81) were comparable to the 10-item Perceived Stress Scale (item-total correlations = .20-.56; split-half coefficient = .82). Reproducibility of the 4-item scale after a 1-week interval (r = .67, ICC absolute agreement = .64) was similar to the 10-item scale (r = .70, ICC absolute agreement = .65). The standard error of measurement was slightly higher in the 4-item scale. Scale constructs of the two were identical in exploratory factor analysis. The two scales were highly correlated (r = .93) and showed similar levels of concurrent validity with sleep quality and quality of life. In conclusion, the 4- and 10-item Korean Perceived Stress Scale are similar in psychometric qualities. © 2016 Wiley Periodicals, Inc.


Assuntos
Psicometria , Reprodutibilidade dos Testes , Estresse Psicológico/psicologia , Adulto , Feminino , Humanos , Masculino , Qualidade de Vida , República da Coreia , Estudantes de Enfermagem/psicologia , Inquéritos e Questionários
7.
Nanoscale ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012309

RESUMO

This study aimed to evaluate the SiO2 atomic layer etching (ALE) process that is selective to Si3N4 based on the physisorption of high boiling point perfluorocarbons (HBP PFCs; C5F8, C7F14, C6F6, and C7F8 have boiling points above room temperature). The lowering of the substrate temperature from 20 °C to -20 °C not only increased SiO2 etch depth per cycle (EPC) but also increased etch selectivity of SiO2/Si3N4 to near infinity. Due to the differences in fluorocarbon adsorption at a temperature during the physisorption depending on boiling points of PFCs, the desorption time and ion bombardment energy during the desorption step needed to be optimized, and higher ion bombardment energy and longer desorption time were required for higher HBP PFCs. Even though near infinity etch selectivity of SiO2/Si3N4 was obtained, for the SiO2 etching masked with Si3N4 patterns, due to the adsorption of PFC on the sidewall of the Si3N4 layer, the difficulty in anisotropic etching could be observed. By adding an O2 descumming step in ALE processes, an anisotropic SiO2 etch profile could be obtained with no adsorption of fluorocarbon on the chamber wall. Therefore, it is believed that the HBP ALE processes can be applicable for achieving high selective SiO2/Si3N4 with more stability and reliability.

8.
J Korean Acad Nurs ; 53(3): 324-339, 2023 Jun.
Artigo em Coreano | MEDLINE | ID: mdl-37435763

RESUMO

PURPOSE: This study aimed to valuate the reliability and validity of the Korean version of the 5C Psychological Antecedents of Vaccination (K-5C) scale. METHODS: The English version of the 5C scale was translated into Korean, following the World Health Organization guidelines. Data were collected from 316 community-dwelling adults. Content validity was evaluated using the content validity index, while construct validity was evaluated through confirmatory factor analysis. Convergent validity was examined by assessing the correlation with vaccination attitude, and concurrent validity was evaluated by examining the association with coronavirus disease 2019 (COVID-19) vaccination status. Internal consistency and test-retest reliability were also evaluated. RESULTS: Content validity results indicated an item-level content validity index ranging from .83 to 1, and scale-level content validity index, averaging method was .95. Confirmatory factor analysis supported the fit of the measurement model, comprising a five-factor structure with a 15-item questionnaire (RMSEA = .05, SRMR = .05, CFI = .97, TLI = .96). Convergent validity was acceptable with a significant correlation between each sub-scale of the 5C scale and vaccination attitude. In concurrent validity evaluation, confidence, constraints, and collective responsibility of the 5C scale were significant independent predictors of the current COVID-19 vaccination status. Cronbach's alpha for each subscale ranged from .78 to .88, and the intraclass correlation coefficient for each subscale ranged from .67 to .89. CONCLUSION: The Korean version of the 5C scale is a valid and reliable tool to assess the psychological antecedents of vaccination among Korean adults.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Reprodutibilidade dos Testes , Vacinação , República da Coreia
9.
Asia Pac J Oncol Nurs ; 10(11): 100309, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37928414

RESUMO

Objective: This narrative review aims to (1) identify neuropsychological tests for assessing cognitive function impairment in patients with cancer, specifically in the domains of attention and memory, (2) summarize the characteristics of these tests, including cognitive function domains, test content, readability, and psychometric quality, and (3) evaluate the feasibility of each test in cancer care. Methods: Data sources include published test manuals, documents from official web pages, and published journal articles. Results: Our study identified eight neuropsychological tests that are most frequently used to assess the attention and memory domains of objective cognitive function in patients with breast cancer. These tests include the California Verbal Learning Test, Hopkins Verbal Learning Test, Rey Auditory Verbal Learning Test, Rey-Osterrieth Complex Figure, CNS Vital Signs, Wechsler Adult Intelligence Scale, Wechsler Memory Scale, and Trail Making Test. They demonstrate acceptable evidence of psychometric quality and varying degrees of feasibility. Test feasibility is influenced by factors such as short testing time, brevity and comprehensiveness, clear cognitive domain distinctions, availability of normative data, minimal practice effects, ease of administration, and limited attention-span requirements. These attributes determine a test's feasibility for use in cancer care. Among the evaluated measures, the California Verbal Learning Test for memory, the Trail Making Test for attention, and the CNS Vital Signs for comprehensive assessment emerge as the most practical choices for cancer care. Conclusions: The assessment and management of cognitive function impairment are crucial for enhancing the quality of life in cancer survivors. Nurses should possess knowledge of assessment tools for early detection and the ongoing monitoring of this symptom's progression.

10.
J Psychosom Res ; 173: 111455, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37586292

RESUMO

OBJECTIVE: This study examined (a) whether there are a subgroup of cancer patients experiencing the selected psycho-neurological symptoms as a cluster (depression, cognitive impairment, fatigue, sleep disturbance, and pain); (b) whether demographic and clinical characteristics and pro-inflammatory cytokines (IL-1α, IL-1ß, IL-4, IL-6, TNF-alpha) are associated with subgroup membership; and (c) whether the activity of indolamine-2.3 dioxygenase(IDO) is associated with pro-inflammatory cytokine activity and psycho-neurological symptom cluster experience. METHODS: This was a prospective cohort study where 149 hematologic patients were recruited from a university hospital and 65 healthy volunteers provided control data. Latent profile analyses were conducted to identify subgroups at two time points: the last day of chemotherapy and 1 week after chemotherapy completion. Influencing factors of subgroup membership were examined by logistic regression. RESULTS: A substantial number of patients (33%, 34% at each time point) experienced the selected psycho-neurological symptoms as a cluster. Older age and elevated IL-1α and IL-6 were associated with experiencing the psycho-neurological symptom cluster. IDO activity was higher in the patients experiencing psycho-neurological symptom cluster; and was positively associated with IL-6. Symptom severity, IL-1α, IL-6, and IDO activity were all significantly higher in cancer patients than in the healthy controls. The findings were preserved across time points. CONCLUSIONS: The activation of pro-inflammatory cytokines and their cross-talk with IDO may be a common biological mechanism, underlying a psycho-neurological symptom cluster experience. The novel approaches for symptom assessment and management can be developed by assessing multiple psycho-neurological symptoms as a cluster and by targeting their common biological pathway.


Assuntos
Dioxigenases , Neoplasias Hematológicas , Neoplasias , Humanos , Triptofano/metabolismo , Triptofano/uso terapêutico , Cinurenina/metabolismo , Citocinas , Fator de Necrose Tumoral alfa , Interleucina-6 , Interleucina-4/uso terapêutico , Síndrome , Estudos Prospectivos , Neoplasias/psicologia
11.
Cancer Nurs ; 46(3): E159-E168, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35324504

RESUMO

BACKGROUND: Findings from longitudinal studies can provide more conclusive evidence as to the impact of chemotherapy on cognitive functioning. OBJECTIVES: This study aimed to ( a ) synthesize the evidence from longitudinal studies of the neuropsychological effects associated with chemotherapy in breast cancer patients, ( b ) identify associated factors, and ( c ) evaluate methodological issues. METHODS: Data were extracted from PubMed, EMBASE, CINAHL, PsycINFO, and the Cochrane Library. Inclusion criteria included the original study with the breast cancer sample, validated measure, and at least 1 baseline data point before and after chemotherapy began. Data accrued for sample characteristics, data-collection time points, statistical methods for longitudinal data analysis, outcome measures, and major findings (eg, longitudinal changes in cognitive function). RESULTS: We selected 42 articles for this review. The sample sizes ranged from 20 to 610, and most recruited were younger than 70 years. We found a trend across studies-statistically significant objective cognitive function deteriorations in severity and prevalence after initiating chemotherapy compared with a control group or relative to their baseline observations. A subsample, as high as 65%, experienced marked declines in cognitive function after initiating chemotherapy. The memory domain was most affected. The consistently associated factors were education, IQ, and regimen. Major methodological concerns were the measurement-the wide range of neuropsychological tests and a test's unclear domains. CONCLUSION: Chemotherapy affects objective cognitive function in some subsets. The highest-impact time point, mechanisms, and clinical significance of chemotherapy-associated cognitive impairment need additional evidence. IMPLICATION FOR PRACTICE: Clinicians must assess and manage cognitive impairment during and after chemotherapy.


Assuntos
Neoplasias da Mama , Transtornos Cognitivos , Disfunção Cognitiva , Humanos , Feminino , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/psicologia , Disfunção Cognitiva/induzido quimicamente , Cognição , Estudos Longitudinais , Testes Neuropsicológicos
12.
Ann Rehabil Med ; 47(5): 403-425, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37907232

RESUMO

OBJECTIVE: : To translate and culturally adapt the Information Needs in Cardiac Rehabilitation (INCR) questionnaire into Korean and perform psychometric validation. METHODS: : The original English version of the INCR, in which patients are asked to rate the importance of 55 topics, was translated into Korean (INCR-K) and culturally adapted. The INCR-K was tested on 101 cardiac rehabilitation (CR) participants at Kangwon National University Hospital and Seoul National University Bundang Hospital in Korea. Structural validity was assessed using principal component analysis, and Cronbach's alpha of the areas was computed. Criterion validity was assessed by comparing information needs according to CR duration and knowledge sufficiency according to receipt of education. Half of the participants were randomly selected for 1 month of re-testing to assess their responsiveness. RESULTS: : Following cognitive debriefing, the number of items was reduced to 41 and ratings were added to assess participants' sufficient knowledge of each item. The INCR-K structure comprised eight areas, each with sufficient internal consistency (Cronbach's alpha>0.7). Criterion validity was supported by significant differences in mean INCR-K scores based on CR duration and knowledge sufficiency ratings according to receipt of education (p<0.05). Information needs and knowledge sufficiency ratings increased after 1 month of CR, thus supporting responsiveness (p<0.05). CONCLUSION: : The INCR-K demonstrated adequate face, content, cross-cultural, structural, and criterion validities, internal consistency, and responsiveness. Information needs changed with CR, such that multiple assessments of information needs may be warranted as rehabilitation progresses to facilitate patient-centered education.

13.
J Nurs Res ; 30(3): e206, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35446277

RESUMO

BACKGROUND: The Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) instrument is a fatigue measure widely used on patients with cancer worldwide. The psychometric quality of the Korean version of the FACIT-Fatigue instrument has never been systematically evaluated. PURPOSE: The purpose of this study was to assess the reliability and validity of the Korean version of the FACIT-Fatigue instrument. METHODS: This study used data collected from 170 patients with cancer and 120 healthy individuals. Internal consistency reliability was analyzed using Cronbach's α and item-total correlation. Construct validity was analyzed using confirmatory factor analysis, and known-group validity was tested using t tests. Convergent validity was analyzed using Pearson's correlation with pain and functional limitations. Predictive validity was analyzed using receiver operating characteristic curves. RESULTS: The Cronbach's α was .93 for the reliability evaluation, and the item-total correlation ranged from .27 to .84. In the construct validity evaluation, the bifactor model showed good fit (Q = 1.93, comparative fit index = .97, Tucker-Lewis index = .96, root mean square error of approximation = .05), indicating using the instrument's total score to be more appropriate than using the subscale scores (explained common variance = .76, ω = .95, ωH = .85, ωH/ω = .89). The group of patients with cancer showed significantly higher fatigue than the healthy subject group, showing known-group validity (t = -10.40, p < .05). Fatigue showed significant and strong correlations with functional limitations and pain (all ps < .001). The area under the curve was .81 (cutoff point = 40, Youden's index: 0.47, sensitivity: 77.60%, specificity: 73.04%), verifying that the instrument is predictive of higher fatigue severity in patients with cancer. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: The Korean version of the FACIT-Fatigue instrument was shown to be reliable and valid. Its construct validity supports the use of the total scale score rather than the subscale scores.


Assuntos
Doença Crônica , Fadiga , Neoplasias , Doença Crônica/terapia , Fadiga/diagnóstico , Fadiga/etiologia , Humanos , Neoplasias/complicações , Neoplasias/terapia , Dor/etiologia , Psicometria , Qualidade de Vida , Reprodutibilidade dos Testes , República da Coreia , Inquéritos e Questionários
14.
RSC Adv ; 12(33): 21520-21547, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35975063

RESUMO

Pristine graphene has been considered one of the most promising materials because of its excellent physical and chemical properties. However, various defects in graphene produced during synthesis or fabrication hinder its performance for applications such as electronic devices, transparent electrodes, and spintronic devices. Due to its intrinsic bandgap and nonmagnetic nature, it cannot be used in nanoelectronics or spintronics. Intrinsic and extrinsic defects are ultimately introduced to tailor electronic and magnetic properties and take advantage of their hidden potential. This article emphasizes the current advancement of intrinsic and extrinsic defects in graphene for potential applications. We also discuss the limitations and outlook for such defects in graphene.

15.
Eur J Oncol Nurs ; 57: 102099, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35255262

RESUMO

PURPOSE: This meta-analysis with longitudinal prospective cohort studies aimed to (a) determine whether chemotherapy is associated with time-dependent subjective cognitive impairment outcomes in breast cancer patients, and (b) identify the time point with the highest impact of chemotherapy on subjective cognitive impairment. METHODS: Data were gathered from PubMed, EMBASE, CINAHL, PsycInfo, and the Cochrane Library. The mean differences of the subjective cognitive impairment level between the chemotherapy-treated patients and controls (patients not treated by chemotherapy and healthy subjects) were calculated using effect sizes (Hedges' g) by clinical time periods. The five clinical time periods were (a) baseline, (b) during chemotherapy, (c) within 1 month postchemotherapy, (d) within 1 year postchemotherapy, and (e) 1 year or longer postchemotherapy. RESULTS: Longitudinal data from nine data sets from 13 studies were pooled and analyzed. At baseline, chemotherapy-treated patients showed slightly better subjective cognitive impairment compared to patients not treated by chemotherapy and did not differ from healthy controls. Yet, the chemotherapy-treated patients had significantly worse subjective cognitive impairment compared to both type of controls after initiating chemotherapy. The effect sizes for the group differences were larger for the group comparison with healthy controls than the nonchemotherapy control (-0.50 vs. -0.19). The largest effects were found within 1 month postchemotherapy (-0.85), suggesting the acute impact of chemotherapy. CONCLUSIONS: Chemotherapy is associated with subjective cognitive impairment. The impact of chemotherapy appears to be an acute rather than a chronic side effect. Clinicians must consider including the assessment and management of subjective cognitive impairment in their routine practice.


Assuntos
Neoplasias da Mama , Disfunção Cognitiva , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/efeitos adversos , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/diagnóstico , Feminino , Humanos , Estudos Longitudinais , Estudos Prospectivos
16.
ACS Nano ; 16(6): 8974-8982, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35621270

RESUMO

The topological Hall effect has been observed in magnetic materials of complex spin structures or bilayers of trivial magnets and strong spin-orbit-coupled systems. In view of current attention on dissipationless topological electronics, the occurrence of the topological Hall effect in new systems or by an unexpected mechanism is fascinating. Here, we report a robust topological Hall effect generated in bilayers of a ferromagnet and a noncoplanar antiferromagnet, from the interfacial Dzyaloshinskii-Moriya interaction due to the exchange coupling of magnetic layers. Molecular beam epitaxy has been utilized to fabricate heterostructures of a ferromagnetic metal Cr2Te3 and a noncoplanar antiferromagnet Cr2Se3. A significant topological Hall effect at low temperature implies the development of nontrivial spin chirality, and density functional theory calculations explain the correlation of the Dzyaloshinskii-Moriya interaction increase and inversion symmetry breaking at the interface. The presence of noncoplanar ordering in the antiferromagnet plays a pivotal role in producing the topological Hall effect. Our results suggest that the exchange coupling in ferromagnet/noncoplanar antiferromagnet bilayers could be an alternative mechanism toward topologically protected magnetic structures.

17.
Clin Nurs Res ; 30(6): 809-817, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32959682

RESUMO

This study examined whether (a) cancer patients in two cohorts reported greater subjective cognitive impairment (SCI) in prevalence and severity than noncancer healthy controls; and (b) selected psychoneurological factors (fatigue, stress, and sleep disturbance) contribute to such differences. Data from 60 prechemotherapy cancer patients, 81 active-chemotherapy cancer patients, and 116 noncancer healthy controls were analyzed using hierarchical regressions. The prevalence rate of SCI was higher in the prechemotherapy cancer cohort (41.6%) and in the active-chemotherapy cancer cohort (46.9%) than in healthy controls (21.5%; p < .001). SCI severity was also higher in two cancer cohorts than noncancer controls (p < .001). The two cancer cohorts were similar to each other in severity and prevalence of SCI. The two cancer cohorts experienced higher fatigue, stress, and sleep disturbance than healthy controls. After controlling for psychoneurological factors, however, the two cancer cohorts did not differ from healthy controls in experiencing SCI in prevalence and severity. Psychoneurological factors may be a major determinant of the higher prevalence and severity of SCI in cancer patients.


Assuntos
Disfunção Cognitiva , Neoplasias , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Fadiga/epidemiologia , Voluntários Saudáveis , Humanos , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Prevalência
18.
Materials (Basel) ; 14(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34442970

RESUMO

Transparent heat films (THFs) are attracting increasing attention for their usefulness in various applications, such as vehicle windows, outdoor displays, and biosensors. In this study, the effects of induction power and radio frequency on the welding characteristics of silver nanowires (Ag NWs) and Ag NW-based THFs were investigated. The results showed that higher induction frequency and higher power increased the welding of the Ag NWs through the nano-welding at the junctions of the Ag NWs, which produced lower sheet resistance, and improved the adhesion of the Ag NWs. Using the inductive welding condition of 800 kHz and 6 kW for 60 s, 100 ohm/sq of Ag NW thin film with 95% transmittance at 550 nm after induction heating could be decreased to 56.13 ohm/sq, without decreasing the optical transmittance. In addition, induction welding of the Ag NW-based THFs improved haziness, increased bending resistance, enabled higher operating temperature at a given voltage, and improved stability.

19.
ACS Nano ; 15(4): 6540-6550, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33784072

RESUMO

Silver-based nanomaterials have been versatile building blocks of various photoassisted energy applications; however, they have demonstrated poor electrochemical catalytic performance and stability, in particular, in acidic environments. Here we report a stable and high-performance electrochemical catalyst of silver telluride (AgTe) for the hydrogen evolution reaction (HER), which was synthesized with a nanoporous structure by an electrochemical synthesis method. X-ray spectroscopy techniques on the nanometer scale and high-resolution transmission electron microscopy revealed an orthorhombic structure of nanoporous AgTe with precise lattice constants. First-principles calculations show that the AgTe surface possesses highly active catalytic sites for the HER with an optimized Gibbs free energy change of hydrogen adsorption (-0.005 eV). Our nanoporous AgTe demonstrates exceptional stability and performance for the HER, an overpotential of 27 mV, and a Tafel slope of 33 mV/dec. As a stable catalyst for hydrogen production, AgTe is comparable to platinum-based catalysts and provides a breakthrough for high-performance electrochemical catalysts.

20.
Medicine (Baltimore) ; 99(7): e19074, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32049808

RESUMO

Eight Constitution Medicine (ECM) is a Korean constitutional medicine system that classifies people into 8 types: Pulmotonia (PUL), Colonotonia (COL), Renotonia (REN), Vesicotonia (VES), Pancreotonia (PAN), Gastrotonia (GAS), Hepatonia (HEP), and Cholecystonia (CHO). Metabolic syndrome (MS) is a major public health problem worldwide. We assessed the prevalence of and associations between ECM and MS. Cross-sectional convenience sample of 245 adults was used at a medical check-up center in Seoul, South Korea, from 2010 to 2015. Adults were classified into 1 of 8 constitutions by an ECM specialist. MS was diagnosed on the basis of National Cholesterol Education Program Adult Treatment Panel III and Asian Pacific Criteria for abdominal obesity. We also computed the prevalence by percentage and calculated odds ratios (ORs) for MS among 6 constitutions with PUL as the reference.Among 245 adults, 20 (8.2%) were diagnosed with PUL, 43 (17.6%) with COL, 35(14.3%) with REN, 4 (1.6%) with VES, 71 (29.0%) with PAN, 0 (0.0%) with GAS, 54 (22.0%) with HEP, and 18 (7.3%) with CHO. The prevalence of MS in the constitutions was significantly different: CHO, 38.9%; HEP, 35.2%; PAN, 18.3%; COL, 11.6%; PUL, 5.0%; REN, 2.9% (P = .001). We observed higher ORs for HEP and CHO (OR = 13.03, 95% confidence interval [CI] = 1.61-105.70; and OR = 13.19, 95% CI = 1.39-125.46, respectively) than for the other constitutions.People with HEP and CHO constitutions could be at higher risk for MS. Therefore, ECM-based diagnosis may be useful for preventing and managing MS.


Assuntos
Síndrome Metabólica/classificação , Síndrome Metabólica/epidemiologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , República da Coreia/epidemiologia , Medicina Estatal
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