Quasiparticle band alignment and stacking-independent exciton in MA2_2Z4_4 (M = Mo, W, Ti; A= Si, Ge; Z = N, P, As)

Motivated by the recently synthesized two-dimensional semiconducting MoSi$_2$N$_4$, we systematically investigate the quasiparticle band alignment and exciton in monolayer MA$_2$Z$_4$ (M = Mo, W, Ti; A= Si, Ge; Z = N, P, As) using ab initio GW and Bethe-Salpeter equation calculations. Compared with the results from density functional theory (DFT), our GW calculations reveal substantially more significant band gaps and different absolute quasiparticle energy but predict the same types of band alignments

Evaluation of the southerly low‐level jet climatology for the central United States as simulated by NARCCAP regional climate models

An ensemble of simulations from four regional climate models (RCMs) driven by a global reanalysis was obtained from the North American Regional Climate Change Assessment Program (NARCCAP) and used to evaluate the ability of the RCMs to simulate the long‐term (1979–2000) climatology of southerly low‐level jets (S‐LLJs) in the central United States. The RCM‐derived S‐LLJ climatologies were evaluated against rawinsonde observations for the same period. The use of a small ensemble of RCM simulations helped to identify model differences and assisted with interpretation. The RCMs generally reproduced the broad spatial patterns and temporal variations of jet frequency and average jet height and speed. No model consistently outperformed the others in all aspects of the evaluation, although differences existed between models in the placement, migration and relative strength of ‘hotspots’ of more frequent jet activity. In particular, three of the four models placed the centre of greatest nocturnal S‐LLJ activity during the warm season in northern and central Texas, whereas for the other model the greatest jet activity was located in the south‐central plains (Kansas/Oklahoma). The magnitude of a S‐LLJ frequency maximum over south Texas also varied between models, with simulated frequencies exceeding observed frequencies for some models but substantially underestimating for others. The evaluation presented here highlights the potential applications of RCMs in S‐LLJ research for future climate and other assessment studies that require three‐dimensional data with relatively high spatial and temporal resolutions. The overall performance of the models in reproducing the long‐term S‐LLJ climatology supports the use of NARCCAP RCM simulations in climate assessments for the central United States where S‐LLJs are an important contributor to the regional climatology.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134503/1/joc4636_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134503/2/joc4636.pd

Wintertime evolution of the temperature inversion in the Colorado Plateau basin.

ABSTRACT The Colorado Plateau, surrounded by a ring of mountains, has the meteorological characteristics of a basin. Deep, persistent potential temperature inversions form in this basin in winter. The formation, maintenance, and dissipation of these inversions are investigated using two to four times daily radiosonde data from the winter and early spring of 1989-90. In winter, inversion evolution is forced primarily by synoptic-scale events. The buildup takes place over one or more days as warm air advection occurs above the basin with the approach of high pressure ridges. The breakup, which occurs with cold air advection above the basin as troughs approach, can occur over periods less than 12 h. Many approaching troughs modulate inversion strength and depth but are too weak to destroy the persistent inversion. Later in the winter and spring, the radiation-induced nocturnal inversion is destroyed nearly every day by the daytime growth of convective boundary layers from the basin floor and sidewalls

The inter‐annual variability of southerly low‐level jets in North America

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135612/1/joc4708_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135612/2/joc4708.pd

Mild temperature photothermal assisted anti-bacterial and anti-inflammatory nanosystem for synergistic treatment of post-cataract surgery endophthalmitis

Rationale: Endophthalmitis, which is one of the severest complications of cataract surgeries, can seriously threaten vision and even lead to irreversible blindness owing to its complicated microenvironment, including both local bacterial infection and severe inflammation. It is urgent to develop a comprehensive treatment for both anti-bacterial and anti-inflammatory effects. Methods: Herein, we developed AuAgCu2O-bromfenac sodium nanoparticles (AuAgCu2O-BS NPs), which was designed to combine anti-bacterial and anti-inflammatory effects for integrated therapy of endophthalmitis after cataract surgery. The AuAgCu2O-BS NPs could eradicate methicillin-resistant Staphylococcus aureus (MRSA) bacterial strain relied on their photodynamic effects and the release of metal ions (Ag+ and Cu+) by the hollow AuAgCu2O nanostructures mediated mild photothermal effects. The anti-inflammatory drug, bromfenac sodium, released from the nanoparticles were able to significantly reduce the local inflammation of the endophthalmitis and promote tissue rehabilitation. In vivo bacterial elimination and anti-inflammation were confirmed by a postcataract endophthalmitis rabbit model. Results: Excellent antibacterial ability of AuAgCu2O-BS NPs was verified both in vitro and in vivo. Ophthalmological clinical observation and pathologic histology analysis showed prominent treatment of inflammatory reaction. Importantly, the mild temperature photothermal effect not only promoted the release of metal ions and bromfenac sodium but also avoided the thermal damage of the surrounding tissues, which was more suitable for the practical application of ophthalmology due to the complex structure of the eyeball. Moreover, superior biocompatibility was approved by the preliminary toxicity investigations, including low cytotoxicity, negligible damage to major organs, and stable intraocular pressure. Conclusions: Our studies of nanosystem provide a promising synergic therapeutic strategy for postcataract endophthalmitis treatment with favorable prognosis and promise in clinical translations.Peer reviewe