The COVID-19 Sentiment and Office Markets: Evidence from China

This study examines the impact of COVID-19 sentiment on office building rents and vacancy rates in China with a COVID-19 sentiment index constructed based on Baidu search queries on COVID-19-related keywords. We analyzed the data of office buildings and economic data from 2013 Q3 to 2022 Q2 in seven major Chinese cities with a two-stage Error Correction Model framework. We found that a heightened level of COVID-19 sentiment significantly and adversely affects the Chinese office buildings market. Specifically, office building rents decrease more than 8% if a city is exposed to an increase of one unit of COVID-19 sentiment for an entire quarter. The interaction terms model further reveals that the COVID-19 sentiment has a more substantial impact on office building rents where office vacancy is higher, reflecting an asymmetric effect. The findings here support the fear sentiment hypothesis. The findings suggest that a heightened level of investors’ COVID-19 sentiment resulted in a deterioration of office rents, reinforcing the role of investors’ sentiment in the pricing of office buildings. The findings suggest that investors should consider investor sentiment, particularly COVID-19 sentiment, in their decision-making

Di(2-ethylhexyl) phthalate induces apoptosis through mitochondrial pathway in GC-2spd cells

Di(2-ethylhexyl) phthalate (DEHP), a plasticizer of synthetic polymers, is a well-known endocrine disrupting chemical (EDC) and reproductive toxicant. Addressing the unclear mechanism of DEHP-induced reproductive dysfunction, this study used GC-2spd cells to investigate the molecular mechanism involved in the DEHP-induced toxicity in the male reproductive system. The results indicated that the apoptotic cell death was significantly induced by DEHP exposure over 100 μM. Furthermore, DEHP treatment could induce oxidative stress in GC-2spd cells involving in the decrease of superoxide dismutase (SOD) activity (200 μM) and glutathione peroxidase (GSH-Px) activity (50 and 100 μM). In addition, DEHP induction also caused the elevated ratios of Bax/Bcl-2, release of cytochrome c and decomposition of procaspase-3 and procaspase-9 in GC-2spd cells. Taken together, our work provided the evidence that DEHP exposure might induce apoptosis of GC-2spd cells via mitochondria pathway mediated by oxidative stress. © 2016 Wiley Periodicals, Inc. Environ Toxicol, 2016

Engineering Raspberry-like Plasmonic Nanoclusters as Tags in Surface-Enhanced Raman Scattering-Based Immunoassays

Surface-enhanced Raman scattering (SERS) is highly attractive with the advantages of non-destructive performance, high specificity, and ultra-sensitivity. However, it is still a great challenge to design SERS tags with strong and undisturbed SERS signals via a simple method for an SERS-based immunoassay. Herein, a simple one-pot method was developed for the fabrication of SERS nanotags with interior reporters located at the nanogaps between plasmonic structures. Benefiting from the reducibility and easy-to-polymerize properties of aniline, Au3+ ions were reduced and grew into small-sized Au nanoparticles with a thin layer of polyaniline (PANI) by using aniline as the reductant. Following the continuous polymerization and the reduction reactions, PANI-coated Au nanoparticles were assembled into a nanocluster with sub 5 nm gaps, and PANI located at these gaps were used as interior reporters in SERS tags. As proof-of-concept, a histidine-tagged antigen was used as the model analyte for the SERS-based immunoassay. The proposed sensing platform showed the response to the histidine-tagged antigen ranging from 0.1 to 1000 ng mL−1 with a detection limit of 0.01 ng mL−1. The remarkable and undisturbed SERS signals make the proposed SERS tags feasible for detections of biomarkers with a low concentration in complex biological samples

Engineering Raspberry-like Plasmonic Nanoclusters as Tags in Surface-Enhanced Raman Scattering-Based Immunoassays

Surface-enhanced Raman scattering (SERS) is highly attractive with the advantages of non-destructive performance, high specificity, and ultra-sensitivity. However, it is still a great challenge to design SERS tags with strong and undisturbed SERS signals via a simple method for an SERS-based immunoassay. Herein, a simple one-pot method was developed for the fabrication of SERS nanotags with interior reporters located at the nanogaps between plasmonic structures. Benefiting from the reducibility and easy-to-polymerize properties of aniline, Au3+ ions were reduced and grew into small-sized Au nanoparticles with a thin layer of polyaniline (PANI) by using aniline as the reductant. Following the continuous polymerization and the reduction reactions, PANI-coated Au nanoparticles were assembled into a nanocluster with sub 5 nm gaps, and PANI located at these gaps were used as interior reporters in SERS tags. As proof-of-concept, a histidine-tagged antigen was used as the model analyte for the SERS-based immunoassay. The proposed sensing platform showed the response to the histidine-tagged antigen ranging from 0.1 to 1000 ng mL−1 with a detection limit of 0.01 ng mL−1. The remarkable and undisturbed SERS signals make the proposed SERS tags feasible for detections of biomarkers with a low concentration in complex biological samples

Theoretical Study on the Electronic Structure and Magnetic Properties Regulation of Janus Structure of M’MCO2 2D MXenes

Motivated by the recent successful synthesis of Janus monolayer of transition metal (TM) dichalcogenides, MXenes with Janus structures are worthy of further study, concerning its electronic structure and magnetic properties. Here, we study the effect of different transition metal atoms on the structure stability and magnetic and electronic properties of M’MCO2 (M’ and M = V, Cr and Mn). The result shows the output magnetic moment is contributed mainly by the d orbitals of the V, Cr, and Mn atoms. The total magnetic moments of ferromagnetic (FM) configuration and antiferromagnetic (AFM) configuration are affected by coupling types. FM has a large magnetic moment output, while the total magnetic moments of AFM2’s (intralayer AFM/interlayer FM) configuration and AFM3’s (interlayer AFM/intralayer AFM) configuration are close to 0. The band gap widths of VCrCO2, VMnCO2, CrMnCO2, V2CO2, and Cr2CO2 are no more than 0.02 eV, showing metallic properties, while Mn2CO2 is a semiconductor with a 0.7071 eV band gap width. Janus MXenes can regulate the size of band gap, magnetic ground state, and output net magnetic moment. This work achieves the control of the magnetic properties of the available 2D materials, and provides theoretical guidance for the extensive design of novel Janus MXene materials