"Impossible Trinity" between Efficiency, Stability, and Color Purity for Blue OLEDs: Challenges and Opportunities.

Organic light-emitting diodes (OLEDs) have become the cutting-edge technology in the display market. However, compared with green and red stacks, blue stacks still remain an obstacle for OLED technology. There seems to be an "impossible trinity" between efficiency, stability, and color-purity for blue OLEDs.

Synergistic Intramolecular Non-Covalent Interactions Enable Robust Pure-Blue TADF Emitters.

Stability-issues of organic light-emitting diodes (OLEDs) employing thermally activated delayed fluorescence (TADF) require further advancements, especially in pure-blue range of CIE < 0.20, existing a dilemma between color purity and device lifetime. Though improving bond-dissociation-energy (BDE) can effectively improve material intrinsic stability, strategies to simultaneously improve BDE and photophysical performances are still lacking.

Precise Regulation on the Bond Dissociation Energy of Exocyclic C-N Bonds in Various N-Heterocycle Electron Donors via Machine Learning.

Heterocycles with saturated N atoms (HetSNs) are widely used electron donors in organic light-emitting diode (OLED) materials. Their relatively low bond dissociation energy (BDE) of exocyclic C-N bonds has been closely related to material intrinsic stability and even device lifetime. Thus, it is imperative to realize fast prediction and precise regulation of those C-N BDEs, which demands a deep understanding of the relationship between the molecular structure and BDE.

N-Containing NaVTi(PO)/C for Aqueous Sodium-Ion Batteries.

Phosphates featuring a 3D framework offer a promising alternative to aqueous sodium-ion batteries, known for their safety, cost-effectiveness, scalability, high power density, and tolerance to mishandling. Nevertheless, they often suffer from poor reversible capacity stemming from limited redox couples. Herein, N-containing NaVTi(PO) is synthesized for aqueous sodium-ion storage through multi-electron redox reactions.

Photocontrolled chiroptical switch based on the self-assembly of azobenzene-bridged bis-tryptophan enantiomers.

Chirality dynamic tuning plays fundamental roles in chemistry, material science and biological system. Herein, a pair of azobenzene-bridged bis-tryptophan enantiomers (Azo-di-d/l-Trp) were designed and synthesized via simple reactions. With the fuel of glucono-δ-lactone (GdL), releasing protons during its hydrolysis, the alkaline solution of Azo-di-d/l-Trp gradually self-assembled into contrast chiral helical structures and displayed magnitude and mirror image of circular dichroism (CD) signals.

Longevity gene responsible for robust blue organic materials employing thermally activated delayed fluorescence.

The 3-Gen OLED materials employing thermally-activated delayed fluorescence (TADF) combine advantages of first two for high-efficiency and low-cost devices. Though urgently needed, blue TADF emitters have not met stability requirement for applications. It is essential to elucidate the degradation mechanism and identify the tailored descriptor for material stability and device lifetime.

Choroidal thickness, myopia, and myopia control interventions in children: a Meta-analysis and systemic review.

Aim: To investigate changes of choroidal thickness (ChT) in children with myopia and the effect of current myopia control interventions on ChT.

Methods: Major literature databases were searched for studies relevant to myopia in children. All studies used swept-source optical coherence tomography (SS-OCT) or enhanced depth imaging optical coherence tomography (EDI-OCT) to measure the ChT value.

Longitudinal Dynamics of Cellular Responses in Recovered COVID-19 Patients.

Safe and effective vaccines and therapeutics based on the understanding of antiviral immunity are urgently needed to end the COVID-19 pandemic. However, the understanding of these immune responses, especially cellular immune responses to SARS-CoV-2 infection, is limited. Here, we conducted a cohort study of COVID-19 patients who were followed and had blood collected to characterize the longitudinal dynamics of their cellular immune responses.

[Effect of combined administration of electroacupuncture and mesenchymal stem cells on expression of endometrium estrogen receptor and progesterone receptor in thin endometrium rats].

Objective: To investigate the effect of joint administration of electroacupuncture (EA) and bone marrow mesenchymal stem cells (BMMSC) on the expression of estrogen receptor (ER) and progesterone receptor (PR) in thin endometrium rats, so as to explore its mechanisms underlying improvement of conception rate.

Methods: Forty female SD rats were divided into control, model, BMMSC and EA+BMMSC groups. The thin endometrium model was established by intrauterine infusion of 95% ethanol and saline.

[Clinical effect of acupuncture combined with traditional Chinese medicine in treatment of oligozoospermia/asthenozoospermia: a meta-analysis].

Objective: To evaluate the clinical effect of acupuncture combined with Chinese medicine in the treatment of oligozoospermia/asthenozoospermia.

Methods: Randomized controlled trials (RCTs) of acupuncture combined with traditional Chinese medicine (TCM) in the treatment of oligozoospermia/asthenozoospermia published up to February 15, 2019 were searched from databases of CNKI, CBM, Wanfang Data, VIP, PubMed, Embase, and The Cochrane Library. Two reviewers independently performed quality assessment and data extraction of the studies, and RevMan5.

The process of retinal vascularization in retinopathy of prematurity after ranibizumab treatment in China.

Aim: To explore the process of retinal vascularization and risk factors for retinopathy of prematurity (ROP) treated with intravitreal ranibizumab (IVR) as monotherapy.

Methods: Infants with type 1 ROP who received IVR as primary treatment from August 2014 to October 2016 at Peking University People's Hospital's Ophthalmology Department were included in the study. All eyes received 0.

Air Pollution Exposure Model for Individuals (EMI) in Health Studies: Evaluation for Ambient PM2.5 in Central North Carolina.

Air pollution health studies of fine particulate matter (diameter ≤2.5 μm, PM2.5) often use outdoor concentrations as exposure surrogates.

A review of air exchange rate models for air pollution exposure assessments.

A critical aspect of air pollution exposure assessments is estimation of the air exchange rate (AER) for various buildings where people spend their time. The AER, which is the rate of exchange of indoor air with outdoor air, is an important determinant for entry of outdoor air pollutants and for removal of indoor-emitted air pollutants. This paper presents an overview and critical analysis of the scientific literature on empirical and physically based AER models for residential and commercial buildings; the models highlighted here are feasible for exposure assessments as extensive inputs are not required.

[Synthesis and luminescence properties of Y10W2O21:Eu nanophosphor].

In the present paper, a novel nanophosphor, Y10W2O21:Eu was synthesized through a simple and low-cost method: co-precipitation. The results of XRD show that resultant samples are Orthorhombic phase and primitive lattice. The average crystallographic sizes could be confirmed to be approximately 80 nm by means of the Scherrer formula, which are in good agreement with the particles sizes exhibited by SEM.

Correction methods for organic carbon artifacts when using quartz-fiber filters in large particulate matter monitoring networks: the regression method and other options.

Sampling and handling artifacts can bias filter-based measurements of particulate organic carbon (OC). Several measurement-based methods for OC artifact reduction and/or estimation are currently used in research-grade field studies. OC frequently is not artifact-corrected in large routine sampling networks (e.

[The enhancement of 1.5 microm near infrared luminescence in Er3+ and Yb3+ codoped Y2O3 nanocrystalline].

Y0.96 Er0.02 Yb0.

Determinants of Indoor and Personal Exposure to PM(2.5) of Indoor and Outdoor Origin during the RIOPA Study.

Effects of physical/environmental factors on fine particle (PM(2.5)) exposure, outdoor-to-indoor transport and air exchange rate (AER) were examined. The fraction of ambient PM(2.

[Study on concentration quenching and energy transfer in Ln3+ (Ln = Tb, Tm, Eu) in Y2O3 nanocrystal powders].

Nano-powders Y2O3 with various particle sizes and different doping concentrations of Ln (Ln = Tb, Tm, Eu) were prepared by using a combustion technique. The bulky powders doped with concentrations corresponding to nano-powders were obtained by annealing the nano-powders at high temperature. The emission spectra, XRD spectra and TEM were used in the present study.

[Studies on absorption kinetics of scopoletin in rat stomachs and intestines].

Objective: To study absorption kinetics of scopoletin in rat stomachs and intestines.

Method: Rats was cannulated for in situ recirculation. UV and HPLC methods were used to determine the concentrations of phenolsulfonphthalein and scopoletin, respectively.

[Effect of Rehmannia glutinosa Libosch water extraction on gene expression of proinsulin in type 2 diabetes mellitus rats].

Objective: To investigate the mechanisms of treating 2-DM by Rehmannia glutinosa Libosch water extraction (RGLE).

Methods: The mRNA level of proinsulin in rats panreas tissue was examined by semi-quatitativa RT-PCR,and the protein was measured by SDS-PAGE.

Results: The mRNA and protein expressions of proinsulin in RGLE group were higher than those of diabetic model group (P<0.

[Effect of Rehmannia glutinosa water extraction on insulin resistance and gene expression of resistin in type 2 diabetes mellitus rats].

Objective: To investigate the effect of Rehmannia glutinosa water extraction (RGL) on adipose metabolic disorder and gene expression of resistin in type 2 diabetes mellitus rats.

Method: The wistar rats model of 2-DM were induced by high calorie feeding and small dose injection of STZ. Rats were randomly divided into diabetic model group, diabetic model treated with RGL (2.

How does infiltration behavior modify the composition of ambient PM2.5 in indoor spaces? An analysis of RIOPA data.

The indoor environment is an important venue for exposure to fine particulate matter (PM2.5) of ambient (outdoor) origin. In this work, paired indoor and outdoor PM2.

[Preparation of alpha-Gd2 (MoO4)3 red emitting phosphor for white light emitting diodes and its luminescence study].

A novel red phosphor alpha-Gd2 (MoO4)3: Eu was synthesized by conventional solid state reaction method with the starting materials: Gd2O3, MoO3 and Eu2O3. The effects of flux and Eu concentration on the crystal structure, morphology and luminescent properties of the phosphors were investigated. The results showed that non-agglomeration phosphors with regular morphology and fine size were produced after the mixture being calcined at 800 degrees C for 4h with 3% NH4F as flux.

[Quantum efficiency of the 5D0 level of Eu3+ at C2 site in cubic nanocrystalline Y2O3].

In the present the authors are trying to work out how the quantum efficiency depends on the nanocrystalline size. Cubic nanocrystalline Y2O3 : Eu3+ samples were prepared by chemical self-combustion. The bulk Y2O3 : Eu3+ was obtained by annealing the nanocrystalline at 1 000 degrees C for 2 h.