Contemporary fire regimes of Canadian forests have been well documented based on forest fire records between the late 1950s to 1990s. Due to known limitations of fire datasets, an analysis of changes in fire-regime characteristics could not be easily undertaken. This paper presents fire-regime trends nationally and within two zonation systems, the homogeneous fire-regime zones and ecozones, for two time periods, 1959–2015 and 1980–2015. Nationally, trends in both area burned and number of large fires (≥200 ha) have increased significantly since 1959, which might be due to increases in lightning-caused fires. Human-caused fires, in contrast, have shown a decline. Results suggest that large fires have been getting larger over the last 57 years and that the fire season has been starting approximately one week earlier and ending one week later. At the regional level, trends in fire regimes are variable across the country, with fewer significant trends. Area burned, number of large fires, and lightning-caused fires are increasing in most of western Canada, whereas human-caused fires are either stable or declining throughout the country. Overall, Canadian forests appear to have been engaged in a trajectory towards more active fire regimes over the last half century.

HIGHLIGHTS• Pourbaix diagram of Mn-Zn-H 2 O system was used to analyze the charge-discharge processes of Zn/MnO 2 batteries.• Electrochemical reactions with the participation of various ions inside Zn/MnO 2 batteries were revealed.• A detailed explanation of phase evolution inside Zn/MnO 2 batteries was provided.ABSTRACT Aqueous rechargeable Zn/MnO 2 zinc-ion batteries (ZIBs) are reviving recently due to their low cost, non-toxicity, and natural abundance.However, their energy storage mechanism remains controversial due to their complicated electrochemical reactions. Meanwhile, to achieve satisfactory cyclic stability and rate performance of the Zn/MnO 2 ZIBs, Mn 2+ is introduced in the electrolyte (e.g., ZnSO 4 solution), which leads to more complicated reactions inside the ZIBs systems. Herein, based on comprehensive analysis methods including electrochemical analysis and Pourbaix diagram, we provide novel insights into the energy storage mechanism of Zn/MnO 2 batteries in the presence of Mn 2+ . A complex series of electrochemical reactions with the coparticipation of Zn 2+ , H + , Mn 2+ , SO 4 2− , and OH − were revealed. During the first discharge process, co-insertion of Zn 2+ and H + promotes the transformation of MnO 2 into Zn x MnO 4 , MnOOH, and Mn 2 O 3 , accompanying with increased electrolyte pH and the formation of ZnSO 4 ·3Zn(OH) 2 ·5H 2 O. During the subsequent charge process, Zn x MnO 4 , MnOOH, and Mn 2 O 3 revert to α-MnO 2 with the extraction of Zn 2+ and H + , while ZnSO 4 ·3Zn(OH) 2 ·5H 2 O reacts with Mn 2+ to form ZnMn 3 O 7 ·3H 2 O. In the following charge/discharge processes, besides aforementioned electrochemical reactions, Zn 2+ reversibly insert into/extract from α-MnO 2 , Zn x MnO 4 , and ZnMn 3 O 7 ·3H 2 O hosts; ZnSO 4 ·3Zn(OH) 2 ·5H 2 O, Zn 2 Mn 3 O 8 , and ZnMn 2 O 4 convert mutually with the participation of Mn 2+ . This work is believed to provide theoretical guidance for further research on high-performance ZIBs.

HIGHLIGHTS • Various MOF materials were synthesized and investigated as ZIB cathodes. • A long-term stable ZIF-8@Zn anode was proposed by coating ZIF-8 material on the surface of zinc foils. • High-performance aqueous ZIBs were constructed using the Mn(BTC) cathode and the ZIF-8@Zn anode.

Visible-light and infrared-light persistent phosphors are extensively studied and are being used as self-sustained glowing tags in darkness. In contrast, persistent phosphors for higherenergy, solar-blind ultraviolet-C wavelengths (200-280 nm) are lacking. Also, persistent tags working in bright environments are not available. Here we report five types of Pr 3+-doped silicates (melilite, cyclosilicate, silicate garnet, oxyorthosilicate, and orthosilicate) ultraviolet-C persistent phosphors that can act as self-sustained glowing tags in bright environments. These ultraviolet-C persistent phosphors can be effectively charged by a standard 254 nm lamp and emit intense, long-lasting afterglow at 265-270 nm, which can be clearly monitored and imaged by a corona camera in daylight and room light. Besides thermal-stimulation, in bright environments, photo-stimulation also contributes to the afterglow emission and its contribution can be dominant when ambient light is strong. This study expands persistent luminescence research to the ultraviolet-C wavelengths and brings persistent luminescence applications to light.

Climate‐induced vegetation change may be delayed in the absence of disturbance catalysts. However, increases in wildfire activity may accelerate these transitions in many areas, including the western boreal region of Canada. To better understand factors influencing decadal‐scale changes in upland boreal forest vegetation, we developed a hybrid modeling approach that constrains projections of climate‐driven vegetation change based on topo‐edaphic conditions coupled with weather‐ and fuel‐based simulations of future wildfires using Burn‐P3, a spatial fire simulation model. We evaluated eighteen scenarios based on all possible combinations of three fuel assumptions (static, fire‐mediated, and climate‐driven), two fire‐regime assumptions (constrained and unconstrained), and three global climate models. We simulated scenarios of fire‐mediated change in forest composition over the next century, concluding that, even under conservative assumptions about future fire regimes, wildfire activity could hasten the conversion of approximately half of Alberta's upland mixedwood and conifer forest to more climatically suited deciduous woodland and grassland by 2100. When fire‐regime parameter inputs (number of fire ignitions and duration of burning) were modified based on future fire weather projections, the simulated area burned was almost enough to facilitate a complete transition to climate‐predicted vegetation types. However, when fire‐regime parameters were held constant at their current values, the rate of increase in fire probability diminished, suggesting a negative feedback by which a short‐term increase in less‐flammable deciduous forest leads to a long‐term reduction in area burned. Our spatially explicit simulations of fire‐mediated vegetation change provide managers with scenarios that can be used to plan for a range of alternative landscape conditions.

A full understanding of the origin and maintenance of β‐diversity patterns in a region requires exploring the relationships of both taxonomic and phylogenetic β‐diversity (TBD and PBD, respectively), and their respective turnover and nestedness components, with geographic and environmental distances. Here, we simultaneously investigated all these aspects of β‐diversity for angiosperms in China. Specifically, we evaluated the relative importance of environmental filtering vs dispersal limitation processes in shaping β‐diversity patterns. We found that TBD and PBD as quantified using a moving window approach decreased towards higher latitudes across the whole of China, and their turnover components were correlated with latitude more strongly than their nestedness components. When quantifying β‐diversity as pairwise distances, geographic and climatic distances across China together explained 60 and 53% of the variation in TBD and PBD, respectively. After the variation in β‐diversity explained by climatic distance was accounted for, geographic distance independently explained about 23 and 12% of the variation in TBD and PBD, respectively, across China. Overall, our results suggest that environmental filtering based on climatic tolerance conserved across lineages is the main force shaping β‐diversity patterns for angiosperms in China.

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The current study was designed to evaluate the pharmacologic effects of three novel cysteine-containing compounds: S-propyl-l-cysteine (SPC), S-allyl-l-cysteine (SAC), and S-propargyl-l-cysteine (SPRC) on H 2 S production and antioxidant defenses in an acute myocardial infarction (MI) rat model. The enzymatic activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), as well as glutathione redox status and malonaldehyde (MDA) content, also were determined. All three compounds were found to preserve SOD and GPx activities and also tissue GSH levels while reducing the formation of the lipid peroxidation product MDA in ventricular tissues. With immunfluorescence assays, we observed the expression of CSE and Mn-SOD. The morphologic changes of the cardiac cells are seen with both light and electron microscopy. The corresponding pathologic alterations were characterized mainly as loss of adherence between cardiac myocytes and swollen or ruptured mitochondria at the ultrastructural level. Propargylglycine, a selective inhibitor of CSE, abolished the protective effects of each compound used in the current model. Our study provides novel evidence that SPC, SAC, and SPRC have cardioprotective effects in MI by reducing the deleterious effects of oxidative stress by modulating the endogenous levels of H 2 S and preserving the activities of antioxidant defensive enzymes like SOD.