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Strong coupling between surface plasmon resonance (SPR) modes and excitons holds great potential for many chemical and physical applications. However, a clear understanding on how far‐field spectral characteristics of SPR (linewidths and intensity) affect the coupling strength remains unclear because these parameters are difficult to be individually tuned. These spectral characteristics are associated with the damping rate and field enhancement that depend on the morphology of the plasmonic nanostructure. In this work, the influence of the SPR line shape on exciton‐plasmon coupling is systematically investigated by delicately tuning the linewidths and resonance intensities of the plasmonic arrays. It is found that the SPR modes with narrow linewidths or large intensity are favorable for the exciton–plasmon system to achieve strong coupling. The obtained clear relationships between the SPR line shape and coupling strength provide guidance for the design and optimization of exciton‐plasmon coupling systems, favoring the highly efficient manipulation of exciton polaritons and enabling specific applications driven by strong coupling. [ABSTRACT FROM AUTHOR]

We introduce the notion of orthogonal sets for Birkhoff orthogonality, which we will call Birkhoff orthogonal sets in this paper. As a generalization of orthogonal sets in Hilbert spaces, Birkhoff orthogonal sets are not necessarily linearly independent sets in finite-dimensional real normed spaces. We prove that the Birkhoff orthogonal set A = { x 1 , x 2 , ... , x n } (n ≥ 3) containing n − 3 right symmetric points is linearly independent in smooth normed spaces. In particular, we obtain similar results in strictly convex normed spaces when n = 3 and in both smooth and strictly convex normed spaces when n = 4 . These obtained results can be applied to the mutually Birkhoff orthogonal sets studied in recently. [ABSTRACT FROM AUTHOR]

Net ecosystem gas exchange (NEE), a balance between gross ecosystem primary productivity (GPP) and ecosystem respiration (ER), is an important indicator of terrestrial ecosystem CO2 sink or source. Increasing frequency in droughts during different periods of the growing season may affect terrestrial ecosystem carbon (C) balance. However, detecting how drought timing controls ecosystem C processes is insufficiently explored because it is a challenge to accurately monitor and forecast drought dynamics.In a 5‐year (2015–2019) precipitation manipulation experiment in a temperate steppe in northern China, we imposed a 60% decrease in precipitation in the early (April–June, DEP) and late (July–September, DLP) growing seasons in plots under rainout shelters to simulate drought occurrence timing. The responses of GPP, ER and NEE to DEP and DLP were examined to determine how the timing of decreased precipitation affects CO2 fluxes.Both DEP and DLP reduced GPP and ER. Decreased precipitation in the late growing season reduced NEE due to a greater decline in GPP than ER. In contrast, the lack of an effect of DEP on NEE can be attributed to a proportional decline in GPP and ER. Reduced normalized difference vegetation index (NDVI) and GPP induced by decreased precipitation explained the decline in GPP and ER respectively. Drought in the late growing season weakened the ecosystem C sink. The result indicates a low resistance in net C uptake to DLP. However, we did not find evidence that previous precipitation decreases resulted in a lower overall rate of ecosystem C exchange, indicating a high resilience in C processes in this semi‐arid grassland.Synthesis and applications. Our study provides solid evidence that drought in the late growing season weakens ecosystem C sink in the semi‐arid grassland. The findings suggest that management practices aimed at enhancing water availability during the late growing season should be preferred for increasing C sequestration. [ABSTRACT FROM AUTHOR]

While most studies account for the effect of total annual precipitation on aboveground net primary production (ANPP), few studies have demonstrated how decreased precipitation within specific periods of growing season affects ANPP. Using a precipitation manipulation experiment, we assessed the response patterns and underlying mechanisms of ANPP to decreased precipitation in the early (DEP) and late (DLP) growing seasons on a temperate steppe in northern China. The results showed that both DEP and DLP decreased ANPP by averages of 28.3 and 39.4 g m−2, respectively. The decline of ANPP in DEP was primarily attributed to a 20.7 g m−2 decrease in grass and 4.9 g m−2 decrease in sub‐shrubs, whereas the decrease in ANPP in DLP was due to a 36.6 g m−2 decrease in perennial forbs and an 8.7 g m−2 decrease in sub‐shrubs. The reduction in grass ANPP under DEP was likely due to decreased soil moisture and increased specific leaf area of grass during the early growing season, whereas the reduction in perennial forbs ANPP under DLP was mainly caused by decreased soil moisture during late growing season. The decline of sub‐shrubs ANPP under DEP and DLP could be explained by shallow root length of sub‐shrubs in DEP and by high soil temperature in DLP. Our findings demonstrated how droughts timing affects ANPP at both community and functional group levels. Different responses of functional groups to drought timing indicate that future studies should not neglect the role of precipitation timing in regulating ecosystem productivity. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the protective effects and molecular mechanisms of scoparone on ischemia‑reperfusion (I/R) injury in primary cultured cardiac myocytes and rats. An in vivo rat model of I/R injury and an in vitro primary cultured cardiac myocyte model of oxygen‑glucose deprivation/reoxygenation were used to investigate the protective effects of scoparone. Cell viability, lactate dehydrogenase (LDH) release, superoxide dismutase (SOD), creatine kinase (CK) and malondialdehyde (MDA) levels, and reactive oxygen species (ROS) production were subsequently measured. In addition, cell apoptosis was assessed by terminal deoxynucleotidyl‑transferase‑mediated dUTP nick end labeling staining, and myocardial infarct area (IA) was determined by triphenyl tetrazolium chloride staining. Furthermore, the protein expression levels of B‑cell lymphoma 2 (Bcl‑2), Bcl‑2‑associated X protein (Bax), cytochrome c (Cyt C) and caspase‑3 were assessed by western blotting. The results demonstrated that treatment with scoparone markedly increased cell viability, SOD levels and Bcl‑2 protein expression, and decreased LDH release, MDA production, CK levels, ROS concentration, cell apoptotic rate, myocardial IA, and Bax, caspase‑3 and Cyt C protein expression. These findings indicated that scoparone may have a protective effect against I/R injury, thus suggesting that scoparone may be a considered a potential drug for the treatment of I/R injury via the inhibition of oxidative stress and cell apoptosis. [ABSTRACT FROM AUTHOR]