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1.
ACS Nano ; 18(26): 16610-16621, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38889966

RESUMEN

Manipulating the crystallographic orientation of zinc deposition is recognized as an effective approach to address zinc dendrites and side reactions for aqueous zinc-ion batteries (ZIBs). We introduce 2-methylimidazole (Mlz) additive in zinc sulfate (ZSO) electrolyte to achieve vertical electrodeposition with preferential orientation of the (100) and (110) crystal planes. Significantly, the zinc anode exhibited long lifespan with 1500 h endurance at 1 mA cm-2 and an excellent 400 h capability at a depth of discharge (DOD) of 34% in Zn||Zn battery configurations, while in Zn||MnO2 battery assemblies, a capacity retention of 68.8% over 800 cycles is attained. Theoretical calculation reveals that the strong interactions between Mlz and (002) plane impeding its growth, while Zn atoms exhibit lower migration energy barrier and superior mobility on (100) and (110) crystal planes guaranteed the heightened mobility of zinc atoms on the (100) and (110) crystal planes, thus ensuring their superior ZIB performance than that with only ZSO electrolyte, which offers a route for designing next-generation high energy density ZIB devices.

2.
J Colloid Interface Sci ; 665: 32-40, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38513406

RESUMEN

Aqueous zinc-ion batteries (AZIBs), defined by low expenses, superior safety, and plentiful reserves, demonstrate tremendous development potential in energy storage systems at the grid scale. Whereas the cathode instability and the limited diffusion of Zn2+ have impeded the development of AZIBs. Herein, a high-performance K-NH4V4O10 (K-NVO) cathode with K+ doping synthesized successfully through one-step hydrothermal approach. Experiments and density functional theory (DFT) calculations indicate that K-NVO has Zn2+ diffusion pathways with lower barriers for smoother transport, and lower formation energy. The combination of the rapid Zn2+ diffusion and the stable structure results in outstanding electrochemical performance of K-NVO as demonstrated in tests. K-NVO cathode achieves a specific capacity of 406 mAh g-1 at 0.2 A g-1, maintains satisfactory cyclic stability with 81.6 % capacity retention after 1000 cycles at 5 A g-1, and possesses a high energy density of 350.9 Wh kg-1. Furthermore, confirmation of the zinc storage mechanism in K-NVO was carried out through Ex situ tests, such as XRD and XPS. This research contributes a unique perspective to the formulation of high-performance cathode materials for AZIBs.

3.
Small ; 20(26): e2311203, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38233210

RESUMEN

Designing a cost-effective and multifunctional separator that ensures dendrite-free and stable Zn metal anode remains a significant challenge. Herein, a multifunctional cellulose-based separator is presented consisting of industrial waste-fly ash particles and cellulose nanofiber using a facile solution-coating method. The resulting fly ash-cellulose (FACNF) separators enable a high ion conductivity (5.76 mS cm-1) and low desolvation energy barrier of hydrated Zn2+. These features facilitate fast ion transfer kinetics and inhibit water-induced side reactions. Furthermore, experimental results and theoretical simulations confirm that the presence of fly ash particles in FACNF separators effectively accommodate the preferential deposition of Zn(002) planes, due to the weak chemical affinity between Zn(002) plane and fly ash, to mitigate dendrite formation and growth. Consequently, the utilization of FACNF separators causes an impressive cycling performance in both Zn||Zn symmetric cells (1600 h at 2 mA cm-2/1 mAh cm-2) and Zn||(NH4)2V10O25 (NVO) full cells (4000 cycles with the capacity retention of 92.1% at 5 A g-1). Furthermore, the assembled pouch cells can steadily support digital thermometer over two months without generating gas and volume expansion. This work provides new insights for achieving crystallographic uniformity in Zn anodes and realizing cost-effective and long-lasting aqueous zinc-ion batteries (AZIBs).

4.
NPJ Parkinsons Dis ; 9(1): 163, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38092812

RESUMEN

Retinal thickness is related to Parkinson's disease (PD), but its association with the severity of PD is still unclear. We conducted a Mendelian randomized (MR) study to explore the association between retinal thickness and PD. For the two-sample MR analysis, the summary statistics obtained from genome-wide association studies on the thickness of Retinal nerve fiber layer (RNFL) and ganglion cell inner plexiform layer (GCIPL) were employed as exposure, while the summary statistics associated with PD were used as the outcome. The primary approach utilized was inverse variance weighted. To correct for multiple testing, the false discovery rate (FDR) was employed. For sensitivity analysis, an array of robust MR methods was utilized. We found genetically predicted significant association between reduced RNFL thickness and a reduced risk of constipation in PD (odds ratio [OR] = 0.854, 95% confidence interval [CI] (0.782, 0.933), P < 0.001, FDR-corrected P = 0.018). Genetically predicted reduced RNFL thickness was associated with a reduced Unified Parkinson's Disease Rating Scale total score (ß = -0.042, 95% CI (-0.079, 0.005), P = 0.025), and reduced GCIPL thickness was associated with a lower risk of constipation (OR = 0.901, 95% CI (0.821, 0.988), P = 0.027) but a higher risk of depression (OR = 1.103, 95% CI (1.016, 1.198), P = 0.020), insomnia (OR = 1.090, 95% CI (1.013, 1.172), P = 0.021), and rapid eye movement sleep behaviour disorder (RBD) (OR = 1.198, 95% CI (1.061, 1.352), P = 0.003). In conclusion, we identify an association between retinal thickness and non-motor symptoms (constipation, depression, insomnia and RBD) in PD, highlighting the potential of retinal thickness as a biomarker for PD nonmotor symptoms.

5.
J Chem Phys ; 159(3)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37462286

RESUMEN

The facet-dependent adsorption of CO on oxidized and reduced CeO2 single crystal surfaces is reviewed, with emphasis on the effect of CO coverage and the ability of state-of-the-art quantum-mechanical methods to provide reliable energies and an accurate description of the IR vibrational frequency of CO. Comparison with detailed, high-resolution experimental infrared reflection absorption spectroscopy data obtained for single crystal samples allows the assignment of the different CO vibrational bands observed on all three low-index ceria surfaces. Good agreement is achieved with the hybrid density functional theory approach with the HSE06 functional and with saturation coverage. It is shown that CO is very sensitive to the structure of cerium oxide surfaces and to the presence of oxygen vacancies. The combined theoretical-experimental approach offers new opportunities for a better characterization of ceria nanoparticles and for unraveling changes occurring during reactions involving CO at higher pressures.

6.
Int J Ment Health Addict ; : 1-11, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37363770

RESUMEN

Through a two-year follow-up study among 2,845 middle school students, we examined the impact of baseline negative life events (NLE) on follow-up negative copying style (NCS) and Internet addiction (IA), and the mediation of NCS between NLE and IA. We found that all NLE, NCS, and IA were correlated, and that both NLE and NCS were risk factors for IA. Structural equation modeling (SEM) results showed that NLE were associated with increased NCS (ß = 0.17, p < 0.01) and IA (ß = 0.16, p < 0.01), that NCS was associated IA ( ß = 0.33, p < 0 0.01), and that NCS partially mediated the effect of NLE on IA ( ß = 0.17, p < 0.01). This large longitudinal study provided solid empirical evidence that NLE and NCS played important roles in IA among middle school students. Educators and policy makers may adopt corresponding approaches to address IA among this population.

7.
ACS Appl Mater Interfaces ; 15(22): 26718-26727, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37218675

RESUMEN

Rechargeable aqueous zinc-ion batteries (AZIBs) are attracting much attention as high-density energy storage systems owing to their fascinating features with low cost, high safety, and simple manufacturing process. However, the commercialization of Zn anodes is hindered by uncontrollable dendrite growth and water-induced side reactions. Herein, a spontaneous reconstruction of a honeycomb-structural hopeite layer (ZPO) on a Zn metal anode (Zn@ZPO) is rationally developed as a functional protection interface by the liquid-phase deposition strategy. The formed ZPO layer not only promotes ion/charge transport and restrains Zn corrosion but also modulates the preferred deposition orientation of the Zn(002) nanosheet for the dendrite-free Zn anode. Accordingly, the Zn@ZPO symmetric cell exhibits satisfactory cycle lifespans of 1500 h at 1 mA·cm-2/1 mAh·cm-2 and 1400 h at 5 mA m-2/1 mAh·cm-2. When assembled with the (NH4)2V10O25·8H2O (NVO) cathode, the Zn@ZPO||NVO full cell delivers an ultrastable cycling lifespan for 25 000 cycles with a discharge capacity retention of 86.6% at 5 A·g-1. Therefore, this work will pave a novel avenue for constructing dendrite-free AZIBs.

8.
ACS Appl Mater Interfaces ; 15(9): 11940-11948, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36848259

RESUMEN

The attractive advantages of the Zn metal anode and water-based electrolyte, such as inherent safety and low cost, endow the zinc-ion batteries (ZIBs) with great potential in the future energy storage market. However, the severe surface side reactions and dendrites affect the service lifespan and electrochemical performance of ZIBs. Herein, a bifunctional electrolyte additive, l-ascorbic acid sodium (LAA), has been added into ZnSO4 (ZSO) electrolyte (ZSO + LAA) to settle the above issues of ZIBs. On the one hand, the LAA additive tends to adsorb on the Zn anode surface to generate a H2O-resistive passivation layer, which can effectively isolate the H2O corrosion and regulate the Zn2+ ion 3D diffusion, thus inducing a uniform deposition layer. On the other hand, the strong adsorption capacity between LAA and Zn2+ can transform the solvated [Zn(H2O)6]2+ into [Zn(H2O)4LAA], thus reducing the coordinated H2O molecules and further suppressing side reactions. With this synergy effect, the Zn/Zn symmetric battery with the ZSO + LAA electrolyte can deliver a cycle life of 1200 h under 1 mA cm-2, and the Zn/Ti battery also presents an ultrahigh Coulombic efficiency of 99.16% under 1 mA cm-2, greatly superior to the batteries with the ZSO electrolyte. Additionally, the effectiveness of the LAA additive can be further verified in the Zn/MnO2 full battery and pouch cell.

9.
Clin Exp Med ; 23(6): 2001-2008, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36418669

RESUMEN

Coronavirus disease 2019 (COVID-19) is an infectious disease that can develop multiple complications and even be life-threatening. The aim of this study is to summarize current evidence of C-reactive protein's (CRP) predictive value for disease severity and survival of COVID-19 patients, focusing on curing patients and reducing the risk of death. We systematically searched related studies from four large databases: Web of Science, PubMed, China National Knowledge Infrastructure (CNKI), and Wanfang Database, all published between December 2019 and June 2021. Then, we implemented meta-analysis using random-effects models through STATA 15.1 and Review Manager 5.3. We also implemented sensitivity analysis and used funnel plots to check publication bias. From the systematic search of the four databases, we were able to identify 18 studies containing a total of 3052 patients. Meta-analysis results showed that 1) CRP levels were lower in non-severe patients than in severe patients (Standardized Mean Difference (SMD) = - 0.87 mg/L, 95% Confidence Interval (CI) = [ - 1.27, - 0.47], p < 0.001); 2) CRP levels were lower in non-intensive care unit (ICU) patients than in ICU patients (SMD = - 1.39 mg/L, 95% CI = [- 1.68, - 1.11], p < 0.001), and 3) CRP levels were lower in survivors than in non-survivors (SMD =- 1.32 mg/L, 95% CI = [- 1.95, - 0.69], p < 0.001). Sensitivity analysis showed these results were stable. Funnel plots indicated no publication bias. The CRP level may timely reflect disease severity and predict survival of COVID-19 patients and may be worthy of further popularization and application in clinic practice.


Asunto(s)
Proteína C-Reactiva , COVID-19 , Humanos , Proteína C-Reactiva/metabolismo , COVID-19/diagnóstico , Gravedad del Paciente
10.
Am J Eval ; 43(4): 559-583, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36507193

RESUMEN

Knowledge tests used to evaluate child protection training program effectiveness for early childhood education providers may suffer from threats to construct validity given the contextual variability inherent within state-specific regulations around mandated reporting requirements. Unfortunately, guidance on instrument revision that accounts for such state-specific mandated reporting requirements is lacking across research on evaluation practices. This study, therefore, explored how collection and integration of validity evidence using a mixed methods framework can guide the instrument revision process to arrive at a more valid program outcome measure.

11.
Obesity (Silver Spring) ; 30(12): 2363-2375, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36416000

RESUMEN

OBJECTIVE: Despite the high prevalence of obesity and associated health risks in the United States adult population, few primary care providers (PCPs) have time and training to provide weight-management counseling to their patients. This study aims to compare the effect of referral to a comprehensive automated digital weight-loss program, with or without provider email feedback, with usual care on weight loss in patients with overweight or obesity. METHODS: A total of 550 adults (mean [SD], 51.4 [11.2] years, BMI = 35.1 [5.5] kg/m2 , 72.0% female) were enrolled through their PCPs (n = 31). Providers were randomly assigned to refer their patients to a 12-month internet weight-loss intervention only (IWL), the intervention plus semiautomated feedback from the provider (IWL + PCP), or to usual care (EUC). Weight was measured at baseline and at 3, 6, and 12 months. RESULTS: Weight changes (mean [SE]) at 12 months were -0.92 (0.46), -3.68 (0.46), and -3.58 (0.48) kg in the EUC, IWL, and IWL + PCP groups, respectively. Outcomes were significantly different in EUC versus IWL and EUC versus IWL + PCP (p < 0.001), but not in IWL versus IWL + PCP. CONCLUSIONS: Referral by PCPs to an automated weight-loss program holds promise for patients with obesity. Future research should explore ways to further promote accountability and adherence.


Asunto(s)
Programas de Reducción de Peso , Adulto , Humanos , Femenino , Masculino , Retroalimentación , Internet , Pérdida de Peso , Obesidad/terapia , Atención Primaria de Salud
12.
Contemp Clin Trials Commun ; 30: 100999, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36237289

RESUMEN

Background: Suicide remains the 10th leading cause of death in the United States. Many patients presenting to healthcare settings with suicide risk are not identified and their risk mitigated during routine care. Our aim is to describe the planned methodology for studying the implementation of the Zero Suicide framework, a systems-based model designed to improve suicide risk detection and treatment, within a large healthcare system. Methods: We planned to use a stepped wedge design to roll-out the Zero Suicide framework over 4 years with a total of 39 clinical units, spanning emergency department, inpatient, and outpatient settings, involving ∼310,000 patients. We used Lean, a widely adopted a continuous quality improvement (CQI) model, to implement improvements using a centralize "hub" working with smaller "spoke" teams comprising CQI personnel, unit managers, and frontline staff. Results: Over the course of the study, five major disruptions impacted our research methods, including a change in The Joint Commission's safety standards for suicide risk mitigation yielding massive system-wide changes and the COVID-19 pandemic. What had been an ambitious program at onset became increasingly challenging because of the disruptions, requiring significant adaptations to our implementation approach and our study methods. Conclusions: Real-life obstacles interfered markedly with our plans. While we were ultimately successful in implementing Zero Suicide, these obstacles led to adaptations to our approach and timeline and required substantial changes in our study methodology. Future studies of quality improvement efforts that cut across multiple units and settings within a given health system should avoid using a stepped-wedge design with randomization at the unit level if there is the potential for sentinel, system-wide events.

13.
BMC Geriatr ; 22(1): 494, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35676655

RESUMEN

BACKGROUND: Childhood experience has been suggested to affect cognitive function in later life. However, the association between childhood friendship status and cognitive ageing trajectory in middle-aged and older adults has not been fully assessed. This study examined the association between childhood friendship status and cognitive ageing trajectory and identified factors modifying this association. METHODS: We used four waves of data from the China Health and Retirement Longitudinal Study (CHARLS), a national representative longitudinal study of adults aged 45 years or older, 2011-2018. The CHARLS included surveys on childhood friendship and cognitive assessments. Childhood friendship status was categorised as poor, fair, and good. To examine the association between childhood friendship and cognitive ageing trajectory in later life, we applied multilevel linear regression models, and explored potential influences of sociodemographic factors, health status and behaviours, and childhood conditions on this association. RESULTS: Of the 4,350 participants, 1,919 (44.1%) were women. The mean age was 56.29 ± 7.80 years. We found childhood friendship was significantly associated with cognitive ageing trajectory in later life, with a dose-response relationship. After adjusting for covariates, comparing to participants with poor childhood friendships, those with better childhood friendships had lower rates of cognitive decline (ß = 0.12, 95% confidence interval [CI]: 0.03 to 0.22 [interaction term of fair friendship and time]; ß = 0.19, 95% CI: 0.10 to 0.28 [interaction term of good friendship and time]) and higher level of cognitive functions (ß = 0.40, 95% CI: 0.22 to 0.58 [fair friendships]; ß = 0.61, 95% CI: 0.43 to 0.79 [good friendships]). These associations were stronger for those who were female, less educated, and had experienced more adverse childhood experiences. CONCLUSIONS: Childhood friendship is associated with cognitive ageing in later life. Enhancing childhood friendships can play an important role to promote healthy ageing in the future.


Asunto(s)
Disfunción Cognitiva , Jubilación , Anciano , China/epidemiología , Cognición/fisiología , Femenino , Amigos , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Jubilación/psicología
14.
Healthcare (Basel) ; 10(3)2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35326939

RESUMEN

Background: The 14-item version of the Oral Health Impact Profile (OHIP-14) has been widely used as a measure for oral health-related quality of life (OHQoL) since its publication in 1997. However, few studies have examined its psychometric properties and relationship with patient-reported oral health in pregnant women. Aim: To offer empirical evidence for appropriate use of the OHIP-14 among pregnant women in research and clinical practice. Objectives: (1) to empirically investigate the psychometric properties of the OHIP-14, (2) to modify it into the MOHIP-14PW (modified OHIP-14 for pregnant women), and (3) to compare their relationships with patient-reported oral health in pregnant women. Methods: In this real-world study (RWS) from suburban New York clinics, we collected OHIP-14 data from 291 pregnant women and assessed its psychometric properties at the item-, dimension-, and measure-level, including confirmatory factor analysis (CFA) and exploratory factor analysis (EFA). Accordingly, we modified the OHIP-14 into the MOHIP-14PW. Finally, we compared their correlations with patient-reported oral health scores. Results: All OHIP-14 items had severely skewed distributions, and two had a correlation with the patient-reported oral health < 0.1. All seven pairs of items correlated well (0.47 to 0.62), but the Cronbach's alphas indicated suboptimal reliability, with two below 0.70. CFA results offered suboptimal support to the original structure, and EFA found a three-dimensional structure best fitted the data. Therefore, we modified the OHIP-14 into the MOHIP-14PW. CFA on the MOHIP-14PW offered stronger supports, and the Cronbach's alphas increased to 0.92, 0.72, and 0.71. The MOHIP-14PW's dimensions were more meaningful to pregnant women and had stronger relationships with patient-reported oral health than the OHIP-14; the average correlation coefficients increased by 26% from 0.19 in OHIP-14 to 0.24 in the MOHIP-14PW. Conclusions: The original OHIP-14 required modifications at the item-, dimension-, and measure- level, and the MOHIP-14PW had better psychometric properties, easier interpretation, and stronger correlation with patient-reported oral health in low-income pregnant women. Through an interdisciplinary RWS on a large sample of pregnant women, this study offers concrete empirical evidence for the advantages of the MOHIP-14PW over the original OHIP-14.

16.
Artículo en Inglés | MEDLINE | ID: mdl-34886450

RESUMEN

Despite evidence-based guidelines that advocate for dental care during pregnancy, dental utilization among pregnant women remains low, especially among low-income and racial-ethnic minority women. We investigated self-reported dental care referral and self-reported dental care attendance among a group of 298 low-income, largely racial-ethnic minority pregnant women attending two suburban prenatal care clinics that had integrated dental care referrals into their prenatal care according to these guidelines. We administered a questionnaire that asked women: (1) whether they had been referred for care by their prenatal care provider; (2) whether they had been seen by a dentist during pregnancy. Among those women who were eligible for a dental care referral (those who reported having dental symptoms, and those not having a recent dental visit), we found that 73.0% reported that they had indeed been referred for dental care by their prenatal provider, while the remaining women reported either no referral (23.5%, n = 67) or were not sure whether they had been referred (3.5%, n = 10). Among those who reported a dental care referral, 67.3% (n = 140) reported that they saw a dentist during their pregnancy, while of those who reported no dental care referral only 35.1% (n = 27) reported a dental visit (Chi-Sq. = 24.1, df = 1, p < 0.001). Having received a dental referral was a significant predictor of reporting a dental visit during pregnancy, with women who received a referral being 4.6 times more likely to report a dental visit during pregnancy compared to those women who did not report a referral. These results demonstrate that vulnerable pregnant women referred for dental care by their prenatal provider will indeed seek and utilize dental care when offered. This dental referral program may serve as a model for improving the utilization of dental care among this population.


Asunto(s)
Etnicidad , Mujeres Embarazadas , Atención Odontológica , Minorías Étnicas y Raciales , Femenino , Humanos , Grupos Minoritarios , New York , Embarazo , Atención Prenatal , Derivación y Consulta
17.
Medicine (Baltimore) ; 100(9): e24923, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33655955

RESUMEN

ABSTRACT: Recent research has suggested that 6 cm of cervical dilation should be the threshold for the active labor phase, and it has confirmed that epidural analgesia (EA) is a safe method of pain relief during labor. However, the evidence provided for these findings comes mainly from randomized controlled clinical trials (RCTs), which suffer from the limitation of real-world generalizability.To test the generalizability of the conclusions from these previous RCTs, we conducted a prospective cohort, real-world study (RWS) on 400 Chinese term nulliparas. A total of 200 of the participants (the EA group) received EA upon request. The participants in the EA group were further subdivided as follows according to their cervical dilation when the EA administration was initiated (CDE): [EA1 group (CDE < 3 cm), EA2 group (3 cm ≤ CDE < 6 cm), and EA3 group (CDE ≥ 6 cm)]. We compared the labor duration of the EA group versus the non-EA (NEA) group, and the NEA group versus the 3 EA subgroups. We also compared delivery outcomes between the EA and NEA groups.The median total labor duration for the EA group [676 (511-923) minutes] was significantly longer than that of the NEA group [514 (373-721) minutes] (P < 0.001). The median durations of both the first- and second-stages of labor for the EA group [600 (405-855) minutes, 68 (49-97) minutes] were longer than those of the NEA group [420 (300-630) minutes, 50 (32-85) minutes] (P < .001, P < .001)]. In addition, the median total labor durations in both the EA1 [720 (548-958) minutes] and EA2 groups [688 (534-926) minutes] were longer than in the NEA group (P < .001 and P < .001, respectively), and the first- and second-stage labor durations of these subgroups were similar to their total labor durations. A Cox regression analysis showed that EA was associated with longer first-stage labor [hazard ratio (HR) 0.55, 95% confidence interval (CI) 0.42-0.71, P < .001] and longer second-stage labor (HR 0.66, 95% CI 0.51-0.85, P = .001). The delivery modes and neonatal outcomes between the EA and NEA groups were not statistically different, however.Our findings suggest that EA administered before a cervical dilation of 6 cm may be associated with longer total, first-, and second-stage labor durations compared with no EA, while later EA administration is not. In addition, though EA prolongs labor duration, it does not impact delivery outcomes. These results confirm the significance of a 6 cm cervical dilation threshold in real-world labor settings.


Asunto(s)
Analgesia Epidural/métodos , Analgesia Obstétrica/métodos , Trabajo de Parto , Manejo del Dolor/métodos , Adulto , China , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Paridad , Embarazo , Estudios Prospectivos , Valores de Referencia
18.
Qual Life Res ; 29(12): 3185-3186, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33201389
19.
Online J Distance Educ Elearn ; 8(2): 80-89, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32974058

RESUMEN

This article delineates the theory and framework for an innovative child abuse training program for mandated reporters called 'iLookOut'. iLookOut is an online learning delivery system that utilizes mastery learning and self-determination theory in the Core Training program, along with spaced retrieval and retrieval practice in a follow-up micro-learning program that reinforces learning from the Core Training. A cognitive mapping model provides the structure for documenting and organizing the learning content in both the Core training and the follow-up micro-learning program. The article provides a conceptual framework for designing and implementing effective and efficient online learning programs.

20.
J Phys Chem Lett ; 11(18): 7925-7931, 2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32870002

RESUMEN

Polar surfaces of solid oxides are intrinsically unstable and tend to reconstruct due to the diverging electrostatic energy and thus often exhibit unique physical and chemical properties. However, a quantitative description of the restructuring mechanism of these polar surfaces remains challenging. Here we provide an atomic-level picture of the refaceting process that governs the surface polarity compensation of cubic ceria nanoparticles based on the accurate reference data acquired from the well-defined model systems. The combined results from advanced infrared spectroscopy, atomic-resolved transmission electron microscopy, and density functional theory calculations identify a two-step scenario where an initial O-terminated (2 × 2) reconstruction is followed by a severe refaceting via massive mass transport at elevated temperatures to yield {111}-dominated nanopyramids. This significant surface restructuring promotes the redox properties of ceria nanocubes, which account for the enhanced catalytic activity for CO oxidation.

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