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Thermally activated delayed fluorescence (TADF) emitters with a high horizontal orientation are highly essential for improving the external quantum efficiency (EQE) of organic light‐emitting diodes; however, pivotal molecular design strategies to improve the horizontal orientation of solution‐processable TADF emitters are still scarce and challenging. Herein, a phenyl bridge is adopted to connect the double TADF units, and generate a dimerized TADF dendrimer, D4CzBNPh‐SF. Compared to its counterpart with a single TADF unit, the proof‐of‐the‐concept molecule not only exhibits an improved horizontal dipole ratio (78 %) due to the π‐delocalization‐induced extended molecular conjugation, but also displays a faster reversed intersystem crossing rate constant (6.08×106 s−1) and a high photoluminescence quantum yield of 95 % in neat film. Consequently, the non‐doped solution‐processed device with D4CzBNPh‐SF as the emitter achieves an ultra‐high maximum EQE of 32.6 %, which remains at 26.6 % under a luminance of 1000 cd/m2. Furthermore, when using D4CzBNPh‐SF as a sensitizer, the TADF‐sensitized fluorescence device exhibits a high maximum EQE of 30.7 % at a luminance of 575 cd/m2 and a full width at half maximum of 36 nm. [ABSTRACT FROM AUTHOR]

A feasible approach by decorating π-extensions with nitrogen is proposed to realize narrow-band emitting NGs with multiple resonance (MR) effect. Pure blue and green NGs were obtained under mild reaction conditions in high yields. Both NGs featured high photoluminescence quantum yields (>90%) with emission peaks at 454 and 516 nm, small full widths at half maxima (FWHMs) of 18 and 23 nm, and high colour saturation with y-coordinates of 0.083 and 0.73, respectively. OLEDs using these NGs as emitters exhibited ideal blue (459 nm) and green (532 nm) emissions with high colour purity and small FWHMs of 25 and 21 nm, respectively. [ABSTRACT FROM AUTHOR]

With the rapid development of the general aviation industry in China, the influence of high-impact aeronautical weather events, such as aircraft icing, on flight safety has become more and more prominent. On 1 March 2021, an aircraft conducting weather modification operations crashed over Ji'an City, due to severe icing. Using multi-source meteorological observations and atmospheric numerical simulations, we analyzed the meteorological causes of this icing accident. The results indicate that a cold front formed in northwestern China and then moved southward, which is the main weather system in the icing area. Based on the icing index, we conducted an analysis of the temperature, relative humidity, cloud liquid water path, effective particle radius, and vertical flow field, it was found that aircraft icing occurred behind the ground front, where warm-moist airflows rose along the front to result in a rapid increase of water vapor in 600–500 hPa. The increase of water vapor, in conjunction with low temperature, led to the formation of a cold stratiform cloud system. In this cloud system, there were a large number of large cloud droplets. In addition, the frontal inversion increased the atmospheric stability, allowing cloud droplets to accumulate in the low-temperature region and forming meteorological conditions conducive to icing. The Weather Research and Forecasting model was employed to provide a detailed description of the formation process of the atmospheric conditions conducive to icing, such as the uplifting motion along the front and supercooled water. Based on a real case, we investigated the formation process of icing-inducing meteorological conditions under the influence of a front in detail in this study and verified the capability of a numerical model to simulate the meteorological environment of frontal icing, in order to provide a valuable reference for meteorological early warnings and forecasts for general aviation. [ABSTRACT FROM AUTHOR]

Background: Moyamoya disease (MMD) signifies a cerebrovascular disorder with obscure origin and a more rapid and severe progression in children than adults. This investigation aims to uncover age-associated distinctions through proteomic and metabolomic profiling to gain insights into the underlying mechanisms of MMD. Methods: Twelve MMD patients—six children and six adults—along with six healthy controls (HC), participated, each providing a 10 mL blood sample. Serum proteomic and metabolomic analyses were conducted using ultra-performance liquid chromatography and high-resolution mass spectrometry, complemented by bioinformatics to identify differential biomolecules and their interactions. Pathway implications were ascertained using GO and KEGG enrichment analysis. Results: Notable proteomic and metabolomic discrepancies were observed between pediatric and adult MMD subjects. A total of 235 and 216 proteins varied in adult and pediatric cases compared to HCs, with 73 proteins shared. In addition, 129 and 74 anionic, plus 96 and 104 cationic metabolites, were differentially expressed in the pediatric and adult groups, respectively, with 34 anionic and 28 cationic metabolites in common. Age-specific biomolecules further characterized these distinctions. Enrichment analysis pinpointed immunity and inflammation pathways, with vitamin digestion and absorption highlighted as pivotal in pediatric MMD. Conclusion: This study unveils distinct metabolic and proteomic patterns within pediatric and adult MMD patients. The critical role of the vitamin digestion and absorption pathway in the pathogenesis of pediatric MMD offers novel insight into disease mechanisms. [ABSTRACT FROM AUTHOR]

Background: Cornelia de Lange syndrome (CdLS) is an uncommon congenital developmental disorder distinguished by intellectual disorder and distinctive facial characteristics, with a minority of cases attributed to RAD21 variants. Methods: A patient was admitted to the endocrinology department at Peking Union Medical College Hospital, where 2 mL of peripheral venous blood was collected from the patient and his parents. DNA was extracted for whole‐exome sequencing (WES) analysis, and the genetic variation of the parents was confirmed through Sanger sequencing. Results: A 13.3‐year‐old male patient with a height of 136.5 cm (−3.5 SDS) and a weight of 28.4 kg (−3.1 SDS) was found to have typical craniofacial features. WES revealed a pathogenic variant c.1143G>A (p.Trp381*) in the RAD21 gene. He was diagnosed with CdLS type 4 (OMIM #614701). We reviewed 36 patients with CdLS related to RAD21 gene variants reported worldwide from May 2012 to March 2024. Patient's variant status, clinical characteristics, and rhGH treatment response were summarized. Frameshift variants constituted the predominant variant type, representing 36% (13/36) of cases. Clinical features included verbal developmental delay and intellectual disorder observed in 94% of patients. Conclusion: This study reported the third case of CdLS type 4 in China caused by a RAD21 gene variant, enriching the genetic mutational spectrum. [ABSTRACT FROM AUTHOR]

Context Prolactinoma, the most common subtype of pituitary adenoma, is rare in children and adolescents. Clinical presentation and treatment outcomes of prolactinomas in this population have been evaluated insufficiently. Objective To summarize the clinical features, both medication and surgical outcomes of prolactinomas in children and adolescents in a large retrospective cohort from China. Methods A cohort of patients with prolactinomas aged ≤20 years at diagnosis between 2012 and 2021 in Peking Union Medical College Hospital were retrospectively analyzed. Results The cohort comprised 170 patients (115 females and 55 males, median age 16.6 years), with 20.0% (23/115) girls without menarche and 33.3% (18/54) boys in prepuberty. The median maximal diameter was 15.0 mm (61.2% macroadenomas and 4.6% giant adenomas), and the median baseline prolactin (PRL) level was 211.0 ng/mL. Larger sizes and higher PRL levels were observed in girls without menarche at diagnosis and in boys. Most girls presented with menstrual disturbance (86.7%), and boys were frequently bothered by headaches (42.6%), reduced height velocities (25.9%), and delayed puberty (18.2%). Dopamine agonists (DAs) were used as first-line treatment in 133 patients, and the resistance rate was 22.5% (25/111), independently associated with maximal tumor diameters (P =.035). Surgery was performed in 76 patients. Long-term surgical remission rates were 32.9% (25/76) overall, negatively associated with cavernous sinus invasion independently (P =.025), 59.4% (19/32) in noninvasive tumors (64.0% in 25 noninvasive macroadenomas), and 5.0% (1/20) in invasive tumors. Conclusion Pediatric prolactinomas exhibited more severe clinical characteristics in boys and in patients diagnosed during earlier stages of pubertal developments. Given the overall efficacy of PRL normalization by medication and considerable surgical remission rate in noninvasive tumors, DAs remain the first-line recommendation for prolactinomas in children and adolescents, while surgery might be viable for noninvasive tumors. [ABSTRACT FROM AUTHOR]