Preparation of N-doped carbon dots based on starch and their application in white LED

N-doped carbon dots (CDs) were synthesized simply and economically by a one-step hydrothermal method using starch as a carbon source and ethylenediamine (EDA) as a nitrogen dopant. The prepared CDs possess the properties of excitation-wavelength dependence and emit blue fluorescence under the excitation wavelength of 365 nm. CDs/starch composite was prepared to achieve the solid-state emission of CDs and their application in light emitting diode (LED) as fluorescent materials. White LED, with CIE coordinates of (0.33, 0.37) and correlated color temperature of 5462 K, was obtained by combining CDs/starch and ultraviolet LED light source, indicating that starch-based CDs have the promising potential in the field of optoelectronic devicesPeer reviewe

Influence of Substrate Wettability on Colloidal Assembly

In this paper, we presented a detailed discussion about the influence of the substrate wettability on the colloidal assembly and the resultant functionality of the films. It covers the basic assembly principle for colloidal crystals, the basic understanding of the substrate wettability on colloidal assembly, and the detailed explanation of the influence by give a full examples of various assembly from the substrate with distinct wettability, such as superhydrophilic, hydrophilic, hydrophobic, superhydrophobic and hydrophilic-hydrophobic pattern substrate

An Efficient Synthesis and Photoelectric Properties of Green Carbon Quantum Dots with High Fluorescent Quantum Yield

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)To greatly improve the production quality and efficiency of carbon quantum dots (CQDs), and provide a new approach for the large-scale production of high-quality CQDs, green carbon quantum dots (g-CQDs) with high product yield (PY) and high fluorescent quantum yield (QY) were synthesized by an efficient one-step solvothermal method with 2,7-dihydroxynaphthalene as the carbon source and ethylenediamine as the nitrogen dopant in this study. The PY and QY of g-CQDs were optimised by adjusting reaction parameters such as an amount of added ethylenediamine, reaction temperature, and reaction duration. The results showed that the maximum PY and QY values of g-CQDs were achieved, which were 70.90% and 62.98%, respectively when the amount of added ethylenediamine, reaction temperature, and reaction duration were 4 mL, 180 °C, and 12 h, respectively. With the optimised QY value of g-CQDs, white light emitting diodes (white LEDs) were prepared by combining g-CQDs and blue chip. The colour rendering index of white LEDs reached 87, and the correlated colour temperature was 2520 K, which belongs to the warm white light area and is suitable for indoor lighting. These results indicate that g-CQDs have potential and wide application prospects in the field of white LEDs.Peer reviewedFinal Published versio

One-step hydrothermal synthesis of fluorescence carbon quantum dots with high product yield and quantum yield

A one-step hydrothermal synthesis of nitrogen and silicon co-doped fluorescence carbon quantum dots (N,Si-CQDs), from citric acid monohydrate and silane coupling agent KH-792 with a high product yield (PY) of 52.56% and high quantum yield (QY) of 97.32%, was developed. This greatly improves both the PY and QY of CQDs and provides a new approach for a large-scale production of high-quality CQDs. Furthermore, N,Si-CQDs were employed as phosphors without dispersants to fabricate white light-emitting diodes (WLEDs) with the color coordinates at (0.29, 0.32). It is suggested that N,Si-CQDs have great potential as promising fluorescent materials to be applied in WLEDs.Peer reviewe

Decision aids can support cancer clinical trials decisions: Results of a randomized trial

BACKGROUND. Cancer patients often do not make informed decisions regarding clinical trial participation. This study evaluated whether a web-based decision aid (DA) could support trial decisions compared with our cancer center’s website. METHODS. Adults diagnosed with cancer in the past 6 months who had not previously participated in a cancer clinical trial were eligible. Participants were randomized to view the DA or our cancer center’s website (enhanced usual care [UC]). Controlling for whether participants had heard of cancer clinical trials and educational attainment, multivariable linear regression examined group on knowledge, self-efficacy for finding trial information, decisional conflict (values clarity and uncertainty), intent to participate, decision readiness, and trial perceptions. RESULTS. Two hundred patients (86%) consented between May 2014 and April 2015. One hundred were randomized to each group. Surveys were completed by 87 in the DA group and 90 in the UC group. DA group participants reported clearer values regarding trial participation than UC group participants reported (least squares [LS] mean = 15.8 vs. 32, p < .0001) and less uncertainty (LS mean = 24.3 vs. 36.4, p = .025). The DA group had higher objective knowledge than the UC group’s (LS mean = 69.8 vs. 55.8, p < .0001). There were no differences between groups in intent to participate. CONCLUSIONS. Improvements on key decision outcomes including knowledge, self-efficacy, certainty about choice, and values clarity among participants who viewed the DA suggest web-based DAs can support informed decisions about trial participation among cancer patients facing this preference-sensitive choice. Although better informing patients before trial participation could improve retention, more work is needed to examine DA impact on enrollment and retention. IMPLICATIONS FOR PRACTICE: This paper describes evidence regarding a decision tool to support patients’ decisions about trial participation. By improving knowledge, helping patients clarify preferences for participation, and facilitating conversations about trials, decision aids could lead to decisions about participation that better match patients’ preferences, promoting patient-centered care and the ethical conduct of clinical research

Correlates of quality of life in overweight or obese breast cancer survivors at enrollment into a weight loss trial

OBJECTIVE: To examine the correlates of the physical and psychosocial domains of quality of life (QOL) in a cohort of breast cancer survivors participating in a weight loss intervention trial. Available data included information on weight and physical activity, as well as demographic and medical characteristics. METHODS: Correlates of QOL and psychosocial functioning were examined in 692 overweight/obese breast cancer survivors at entry into a weight loss trial. QOL was explored with three measures: Short-form 36 (SF-36); Impact of Cancer Scale (IOCv2); and the Breast Cancer Prevention Trial (BCPT) Symptom Scales. Bivariate and multivariate analyses were used to identify correlates and associations adjusted for other characteristics. RESULTS: In multivariate analysis, younger age was associated with higher negative impact scores (p<0.01). Hispanic, African-American and Asian women had higher IOC positive impact scores compared to white non-Hispanic women (p<0.01). Higher education was associated with lower scores on mental QOL and the IOC positive impact scale (p<0.01). BMI was not independently associated with QOL measures. Physical activity was directly associated with physical and mental QOL and IOC positive impact, and inversely related to IOC negative impact and BCPT symptom scales. CONCLUSIONS: QOL measures in breast cancer survivors are differentially associated with demographic and other characteristics. When adjusted for these characteristics, degree of adiposity among overweight/obese women does not appear to be independently associated with QOL. Among overweight/obese breast cancer survivors, higher level of physical activity is associated with higher QOL across various scales and dimensions

Insight into the effect of hospital-based prehabilitation on postoperative outcomes in patients with total knee arthroplasty: A retrospective comparative study

Background: Osteoarthritis (OA) has become one of the most prevalent joint diseases worldwide, leading to a growing burden of pain and disability as populations age. Although there is consistent evidence to support postoperative rehabilitation and high-intensity prehabilitation for total knee arthroplasty (TKA), the clinical outcomes of hospital-based prehabilitation remain unclear. We aimed to evaluate the effect of a hospital-based prehabilitation program on knee score (KS), function score (FS), and length of stay (LOS) among patients with knee OA after TKA. Methods: A retrospective comparative study was conducted at Renmin Hospital of Wuhan University among patients with primary knee OA. Seventy-two postopearative patients who did not undergo the prehabilitation program were included as the control group, while 68 postoperative patients who underwent the prehabilitation program were assigned to the intervention group. All patients went through the same care after TKA. The KS, FS, and pain levels were measured 5 days before surgery, immediately preceding surgery, immediately after the surgery, and at 1 week and 1 month postoperatively. LOS for each patient was recorded. Results: The new prehabilitation training program significantly improved the KS over time in the intervention group. However, no significant between-group difference was identified in the change of FS. The prehabilitation program also provided shorter LOS. Conclusions: The hospital-based prehabilitation program leads to improved recovery, as indicated by higher KS postoperatively, which may result in improved clinical outcomes of TKA

Comparing statistical methods in assessing the prognostic effect of biomarker variability on time-to-event clinical outcomes

BACKGROUND: In recent years there is increasing interest in modeling the effect of early longitudinal biomarker data on future time-to-event or other outcomes. Sometimes investigators are also interested in knowing whether the variability of biomarkers is independently predictive of clinical outcomes. This question in most applications is addressed via a two-stage approach where summary statistics such as variance are calculated in the first stage and then used in models as covariates to predict clinical outcome in the second stage. The objective of this study is to compare the relative performance of various methods in estimating the effect of biomarker variability. METHODS: A joint model and 4 different two-stage approaches (naïve, landmark analysis, time-dependent Cox model, and regression calibration) were illustrated using data from a large multi-center randomized phase III trial, the Ocular Hypertension Treatment Study (OHTS), regarding the association between the variability of intraocular pressure (IOP) and the development of primary open-angle glaucoma (POAG). The model performance was also evaluated in terms of bias using simulated data from the joint model of longitudinal IOP and time to POAG. The parameters for simulation were chosen after OHTS data, and the association between longitudinal and survival data was introduced via underlying, unobserved, and error-free parameters including subject-specific variance. RESULTS: In the OHTS data, joint modeling and two-stage methods reached consistent conclusion that IOP variability showed no significant association with the risk of POAG. In the simulated data with no association between IOP variability and time-to-POAG, all the two-stage methods (except the naïve approach) provided a reliable estimation. When a moderate effect of IOP variability on POAG was imposed, all the two-stage methods underestimated the true association as compared with the joint modeling while the model-based two-stage method (regression calibration) resulted in the least bias. CONCLUSION: Regression calibration and joint modelling are the preferred methods in assessing the effect of biomarker variability. Two-stage methods with sample-based measures should be used with caution unless there exists a relatively long series of longitudinal measurements and/or strong effect size (NCT00000125)

Urban-rural disparities in access to low-dose computed tomography lung cancer screening in Missouri and Illinois

INTRODUCTION: Low-dose computed tomography (LDCT) lung cancer screening is recommended for current and former smokers who meet eligibility criteria. Few studies have quantitatively examined disparities in access to LDCT screening. The objective of this study was to examine relationships between 1) rurality, sociodemographic characteristics, and access to LDCT lung cancer screening and 2) screening access and lung cancer mortality. METHODS: We used census block group and county-level data from Missouri and Illinois. We defined access to screening as presence of an accredited screening center within 30 miles of residence as of May 2019. We used mixed-effects logistic models for screening access and county-level multiple linear regression models for lung cancer mortality. RESULTS: Approximately 97.6% of metropolitan residents had access to screening, compared with 41.0% of nonmetropolitan residents. After controlling for sociodemographic characteristics, the odds of having access to screening in rural areas were 17% of the odds in metropolitan areas (95% CI, 12%-26%). We observed no association between screening access and lung cancer mortality. Southeastern Missouri, a rural and impoverished area, had low levels of screening access, high smoking prevalence, and high lung cancer mortality. CONCLUSION: Although access to LDCT is lower in rural areas than in urban areas, lung cancer mortality in rural residents is multifactorial and cannot be explained by access alone. Targeted efforts to implement rural LDCT screening could reduce geographic disparities in access, although further research is needed to understand how increased access to screening could affect uptake and rural disparities in lung cancer mortality

A novel SW-ESIW slot antenna and its applications in millimeter-wave array design

A novel structure of slot antenna with high gain and compact size for millimeter-wave (mmW) applications is proposed. This is the first attempt to apply slow-wave substrate integrated waveguide (SW-ESIW) to the field of antennas and their arrays. Two slot antenna arrays were designed, fabricated and measured. The measured results are in agreement with the simulation. The removal of dielectric substrate improves the radiation gain. At the same time, the slow wave effect, by means of physical separation of electric and magnetic fields, decreases both the lateral and longitudinal dimensions of the antenna. The SW-ESIW slot antenna can achieve miniaturization while retaining the advantages of high gain of ESIW. The 1 × 4-slot array shows a measured −10 dB bandwidth of 16% (30.5–35.8 GHz) with a measured maximum gain of 11.69 dB. The 4 × 4-slot array achieves a measured −10 dB bandwidth of 7.6% from 31.6 to 34.1 GHz with a measured peak gain of 18.75 dB. In addition, during the operating band, the radiation pattern is stable. Compared with the previously structures, the proposed SW-ESIW antenna structure has a better trade-off between gain and footprint. It can be flexibly adjusted to adapt to different requirements. These performances ensure that the antenna array based on the proposed structure is a promising candidate for millimeter-wave wireless applications including the fifth-generation mobile communications