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Inorganic persistent luminescence (PersL) nanoparticles (NPs) emitting at the deep-red and near-infrared (NIR) are promising candidates for applications in the biomedical field, such as optical imaging, sensing and therapy. The emission wavelength is closely related to the identity of the light activators (i.e. metal ion dopant), and the local environment they occupy in the host crystal lattice. In this paper, PersL nanoparticles with dual emission bands based on MgGeO 3 was investigated. These nanoparticles exhibit one emission band at the deep-red region when doped with Mn2+. Introducing Yb3+ as a second dopant enables a deep-red-to-NIR energy transfer, producing dual-emission at both deep-red and NIR. The NIR emission can be further enhanced by the addition of Li+. A detailed spectroscopy study is performed to investigate the local structure around the light activators Mn2+ and Yb3+, and how it is influenced by the Li+ co-dopant. We found that adding the Yb3+ and Li+ changes the preferred site of occupancy for Mn2+, and when Mn2+ is shifted to a site that emits deep-red less efficiently, it acts as an electron trap to extend the PersL of the NIR-II emission. The mechanism for the deep-red-to-NIR energy transfer is proposed. • MgGeO 3 :Mn,Yb,Li nanoparticles exhibit dual-band persistent luminescence. • XAFS tracks the change of of Mn2+ site occupancy during co-doping. • The role of Mn2+ changes from a light emitter to a charge trap when Yb3+ is added. • Adding Li+ accelerates the site change of Mn2+ and facilitates Yb3+ incorporation. [ABSTRACT FROM AUTHOR]

The maximum Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) carboxylation rate (V cmax) has been widely used to help determine the photosynthetic capacity for carbon cycle modelling. Field measurements of V cmax are very limited, so fixed V cmax values over growing seasons are often used, causing considerable uncertainties in modelled results. Also, the lack of a global V cmax dataset with seasonal variations limits our understanding of the spatial and temporal patterns of V cmax , and hence photosynthesis. This study proposes a refined data assimilation scheme to retrieve daily V cmax using remotely sensed solar-induced chlorophyll fluorescence (SIF) and leaf chlorophyll content (LCC) data. Using the refined method, we produced a global V cmax dataset with daily 0.1° × 0.1° resolutions. The seasonal variations in V cmax have been successfully retrieved. V cmax retrieved in this study was compared with field-measured V cmax from past literature. Good agreements were achieved in relation to V cmax measured at 201 sites (R2 is 0.78, and relative RMSE is 34%) and the seasonal variation in V cmax measured at 9 sites (R2 ranges from 0.57 to 0.99, and the relative RMSE ranged from 6% to 28%). Our method effectively utilizes the information from both SIF and LCC, showing advantages over previous approaches that estimate V cmax based solely on using SIF or LCC. Our results suggest that the spatial distribution of V cmax depends on the spatial distribution of biomes, along with air temperature and absorbed photosynthetically active radiation (APAR). Higher seasonal mean air temperature and APAR tend to lead to higher seasonal mean V cmax. The seasonal variation in V cmax is driven by the seasonal variations in air temperature and APAR, rather than their seasonal means. We also derived and analyzed V cmax25 , which is V cmax normalized to 25 °C (V cmax25) and has been found to be more closely related to the Rubisco content. V cmax25 also has considerable spatiotemporal variations, and the variations differ to that in V cmax. Different biomes have different ratios of V cmax25 to LCC. Air temperature and APAR exert weak but positive effects on the seasonal variation in V cmax25. V cmax retrieved in this study enhances our understanding of the spatiotemporal pattern of leaf photosynthetic capacity on the global scale and is potentially useful to terrestrial carbon cycle modelling. • Seasonal variations in V cmax are accurately retrieved globally from remotely sensed SIF and LCC • V cmax has considerable spatiotemporal variations among biomes, affected by air temperature and APAR [ABSTRACT FROM AUTHOR]

Objective: Hyperglycemia, inflammation, and oxidative stress are thought to be involved in the pathogenesis of cognitive decline. Dipeptidyl peptidase-4 (DPP4) is a newly identified adipokine related to these risk factors. Hence, we aimed to investigate the association between plasma DPP4 activities and mild cognitive impairment (MCI) in elderly patients with type 2 diabetes.Research Design and Methods: We evaluated plasma DPP4 activity, inflammatory markers, and oxidative stress parameters in a cross-sectional sample of 1,160 patients with type 2 diabetes aged 60 years or older in China. MCI was diagnosed based on criteria established by the National Institute on Aging-Alzheimer's Association workgroupsResults: Patients in the highest quartile of DPP4 activity had higher HbA1c, interleukin 6 (IL-6), CRP, nitrotyrosine, 8-iso-PGF2a, and lower Montreal Cognitive Assessment (MoCA) scores compared with subjects in the lowest quartile (P < 0.001). In the highest DPP4 quartile, MCI risk was higher (odds ratio 3.49; 95% CI 1.97-4.57) than in the lowest quartile after adjustment for potential confounders. The risk for MCI increased more with higher levels of DPP4 activity, IL-6, CRP, nitrotyrosine, and 8-iso-PGF2a (P < 0.05), but not with higher levels of HbA1c.Conclusions: This study shows that increased DPP4 activities are independently associated with MCI in elderly patients with type 2 diabetes. The mechanisms might be partly explained by the effect of DPP4 on inflammation and oxidative stress. These observations raise further interest in DPP4 activity for its potential effect on these MCI-related risk factors as a biological marker or even a possible therapeutic target for MCI. [ABSTRACT FROM AUTHOR]

CaTi 2 O 4 (OH) 2 :Eu3+, CaTiO 3 :Eu3+ and [CaTi 2 O 4 (OH) 2 –CaTiO 3 ]:Eu3+ were synthesized by a solvothermal method without the help of templates or surfactants. And their structures, luminescence properties, and photocatalytic properties were systematically studied. The RIR (reference intensity ratio) data of CaTi 2 O 4 (OH) 2 were first investigated via X-ray diffraction (XRD), thus the ratios of each phase in the (m%CaTi 2 O 4 (OH) 2 -n%CaTiO 3):3%Eu3+ biphasic mixture was determined. The bandgap value of CaTi 2 O 4 (OH) 2 :3%Eu3+ is 0.28 eV less than that of CaTiO 3 :3%Eu3+. The specific surface area of CaTi 2 O 4 (OH) 2 is 8.2 times larger than that of CaTiO 3. Compared with CaTiO 3 :Eu3+, the CaTi 2 O 4 (OH) 2 :Eu3+ showed stronger luminescence intensity. The Judd-Ofelt theory analysis show that the Eu3+ ions in CaTi 2 O 4 (OH) 2 :Eu3+ have low local symmetry, high Eu–O bonds covalence and low ligands electron density. The photocatalytic properties of CaTi 2 O 4 (OH) 2 :y%Eu3+, CaTiO 3 :x%Eu3+ and [62.2%CaTi 2 O 4 (OH) 2 -37.8%CaTiO 3 ]:3% Eu3+ were comparatively studied in detail. The band-gap value of [62.2 % CaTi 2 O 4 (OH) 2 –37.8%CaTiO 3 ]:3%Eu3+ is significantly reduced due to the presence of heterojunctions compared to CaTi 2 O 4 (OH) 2 :y%Eu3+ and CaTiO 3 : x%Eu3+. The built-in electric potential at heterojunction interface will guide electrons and holes to move in opposite directions, therefore [CaTi 2 O 4 (OH) 2 –CaTiO 3 ]:Eu3+ has excellent photocatalytic activity. [Display omitted] [ABSTRACT FROM AUTHOR]