Boron difluoride compounds are light emitting materials with impressive optical properties. Though their strong one- and two-photon absorption and intense fluorescence are well-known and exploited in molecular probes, lasers, and photosensitizers, phosphorescence, in contrast, is typically observed only at low temperatures. Here, we report that unusual room-temperature phosphorescence is achieved by combining a classic boron dye, difluoroboron dibenzoylmethane, BF2dbm, with poly(lactic acid) (PLA), a common biopolymer, resulting in a highly sensitive single-component oxygen sensor. Fluorescence quantum yields are enhanced, and temperature-sensitive delayed fluorescence is also observed. Multi-emissive BF2dbmPLA biomaterials show great promise as multifunctional molecular probes and sensors.

Page 8942. The extinction coefficient for BF 2 dbmPLA (2) is incorrect as reported using the number-average molecular weight, M n , determined by gel permeation chromatography (GPC) in tetrahydrofuran versus polystyrene (PS) standards with a 0.58 PLA correction factor in the calculation. The correct value for this sample, obtained after precipitation from CH 2 CH 2 /cold MeOH (4°C) (2×) and CH 2 CH 2 /hexanes (2×) (residual monomer content <1%, as verified by 1 H NMR spectroscopy), is ) 36 000 M -1 cm -1 . The second sentence of the fourth paragraph should read as follows:UV/vis spectroscopic data for BF 2 dbmOH (λ max ) 397 nm, ) 53 000 M -1 cm -1 ) and BF 2 dbmPLA (λ max ) 396 nm, ) 36 000 M -1 cm -1 ) show high molar absorptivities characteristic of this family of compounds.Calculated epsilon values for BF 2 dbmPLA materials typically range from ∼35 000 to 40 000 M -1 cm -1 , depending on polymer molecular weight and polydispersity index, as determined by GPC versus PS standards (0.58 correction factor). Correct elemental analysis data for 1: C, 61.73; H, 4.56.

A palladium-catalyzed cyanation of the 3-position of indole sp(2) C-H bonds by the combination of NH(4)HCO(3) and DMSO as the "CN" source was achieved to provide aromatic nitriles in moderate to good yields with excellent regioselectivity. It represents a practical and safe cyanation method.

Mesoporous silica nanoparticles grafted with light-responsive polymer on the outer surface were developed as novel nanogated ensembles, which allow encapsulation and release of drug and biological molecules under light irradiation.

The new routes and strategies for the synthesis of valuable 4(3H)-quinazolinones have been summarized.

We investigate the validity of the thermodynamical properties of the universe in a new parametric model of dark energy with the equation of state w = w 0 +w 1 ·z(1+z)/(1+z 2 ). In the spatially homogeneous and isotropic universe, assuming that the temperature and entropy in cosmology is as in a black hole, we examine the thermodynamical properties of the universe bounded by the apparent horizon and the event horizon respectively. By analysis, we find that the first and the second laws of thermodynamics are valid inside the apparent horizon, while they break down inside the event horizon. Keywords: Dark energy; the thermodynamical properties; apparent horizon; event horizon. PACS Nos.: 98.80.-k, 98.80.Cq 885 Mod. Phys. Lett. A 2011.26:885-892. Downloaded from www.worldscientific.com by UNIVERSITY OF CALIFORNIA @ SAN DIEGO on 02/03/15. For personal use only. 886 L. Xing et al.

Highlights 7.7% of college students showed depressive symptoms during the COVID-19 pandemic. College students with depressive symptoms had low regulatory emotional self-efficacy. Browsing COVID-19 information over 3 h per day was related to depressive symptoms. Unfavorable living rhythms were associated with depressive symptoms. Pay attention to college students' mental health during the COVID-19 pandemic.

Background: Coronavirus disease 2019 (COVID-19) has considerably psychologically impacted Chinese college students. Several types of online mental health services were widely implemented for college students during the outbreak. This study investigated the relationship between college students' mental health status and psychological helpseeking behavior to test the phases-decision-making model (PDM). Methods: A cross-sectional survey was conducted among college students in Guangdong Province using an online platform. In total, 4,164 students were assigned to the "counseling group" or "non-counseling group" according to whether they had sought psychological help because of the COVID-19 outbreak; the groups were matched based on age, sex, and grade. Demographics, perceived mental health, and experience with seeking psychological help were recorded. Fear, depression, and trauma were assessed by the COVID-19 Fear Screening Scale, Patient Health Questionnaire, and Impact of Event Scale-6. Results: The fear, depression, and trauma scores were significantly higher in the counseling group than in the non-counseling group (P s < 0.001). Fear (OR = 1.27, p < 0.001), depression (OR = 1.02, p = 0.032), trauma (OR = 1.08, p < 0.001), poor perceived mental health status (OR = 3.61, p = 0.001), and experience with seeking psychological help (OR = 7.06, p < 0.001) increased the odds of seeking psychological help. Conclusion: During the COVID-19 epidemic, the rate of psychological help-seeking was still low, and college students in poor psychological condition sought psychological counseling more. Fear, depression, trauma, experience with seeking psychological help, and perceived mental health can effectively predict psychological help-seeking behavior. These findings emphasized the importance of closely monitoring college students' psychological status, providing psychological intervention, and improving the probability of seeking psychological help.