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Serum albumin-gold complexes exhibit UV-excitable red luminescence (λem = 640 nm) with unusual Stokes shifts compared with the innate UV/blue fluorescence arising from the aromatic residues. In order to understand the mechanism of this luminescence, we employed limited proteolysis and molecular cloning techniques and assessed the domain containing the red luminophore in bovine serum albumin (BSA) and human serum albumin (HSA). We identified that the luminophore is localized in a domain of serum albumin, residing within the N-terminus half.Cost-effective nitrogen-doped monolithic hierarchical carbon cryogels with excellent mechanical properties and carbon dioxide (CO2) adsorption performance were prepared from phenol, melamine and formaldehyde (PMF) by the sol-gel, freeze-drying and then pyrolysis processes under an inert atmosphere. Selleckchem Idelalisib The morphology, mechanical properties, pore structure, and chemical characteristics of these cryogels were investigated. The results showed that the dilution ratio played a crucial role in the preparation of nitrogen-doped PMF carbon cryogels with controlled structures. The prepared carbon cryogels were a kind of monolithic materials composed of a hierarchical pore structure and had high compression properties (0.67MPa and 9.4MPa for strength and modulus), porosity (97.6%), surface area (1406 m2/g), and heteroatom nitrogen content (0.98%~2.09%). CO2 adsorption capacities up to 5.75 mmol/g at 0°C and 4.50 mmol/g at 25°C under 1 bar were obtained, which is at a high level among N doped carbon materials and far better than resorcinol-based carbon gels reported. These superior CO2 adsorption capacities, high isosteric adsorption heat (Qst), and good CO2/N2 adsorption selectivity were ascribed to the synergistic effect of high surface area, appropriate pore size, and also heteroatom doping.Soft carbon is attracting tremendous attention as a promising anode material for potassium-ion batteries (PIBs) because of its graphitizable structure and adjustable interlayer distance. Herein, nitrogen/sulfur dual-doped porous soft carbon nanosheets (NSC) have been prepared with coal tar pitch as carbon precursors in an appropriate molten salt medium. The molten salt medium and N/S dual-doping are responsible for the formation of nanosheet-like morphology, abundant microporous channels with a high surface area of 436 m2 g-1, expanded interlamellar spacing of 0.378 nm, and enormous defect-induced active sites. These structural features are crucial for boosting potassium-ion storage performance, endowing the NSC to deliver a high potassiation storage capacity of 359 mAh g-1 at 100 mA g-1 and 115 mAh g-1 at 5.0 A g-1, and retaining 92.4% capacity retention at 1.0 A g-1 after 1000 cycles. More importantly, the pre-intercalation of K atom from the molten salts helps improve the initial Coulombic efficiency to 50%, which outperforms those of the recently reported carbon anode materials with large surface areas. The density functional theory calculations further illuminate that the N/S dual-doping can facilitate the adsorption of K-ion in carbon materials and decrease the ion diffusion energy barrier during the solid-state charge migration.Increasing evidence shows that warming is driving Hg release from the cryosphere. However, Hg cycling in thawing permafrost is less understood to date. Here we show that permafrost thaw dominantly supplied no-run thermokarst ponds by permafrost melt waters (PMWs) with high concentration of photoreducible Hg (PRHg) and subsequently controlled Hg(0) emissions in the Tibetan Plateau. This study was motivated by field survey suggesting that thermokarst ponds as recipient aquatic systems of PMWs could be an active converter of PRHg to Hg(0). Annual Hg mass balance in three seasonally ice-covered thermokarst ponds suggests that PMWs were the dominant input (81.2% to 91.2%) of PRHg in all three thermokarst ponds, and PRHg input would be a constraint of Hg(0) emission owing to the fast photoreduction of PRHg to Hg(0) in the water column. Annual Hg(0) emission in the thermokarst ponds of study region was conservatively estimated to increase by 15% over the past half century. Our findings highlight that climate-induced landscape disturbances and changes in hydrogeochemical processes in climate-sensitive permafrost will quickly and in situ drive Hg stored in permafrost for a very long time into the modern day Hg cycle, which potentially offsets the anthropogenic Hg mitigation policies.A variety of pathogenic bacteria can infect humans, and rapid species identification is crucial for the correct treatment. However, the identification process can often be time-consuming and depend on the cultivation of the bacterial pathogen(s). Here we present a standalone, enzyme-free, optical DNA mapping assay capable of species identification by matching intensity profiles of large DNA molecules to a database of fully assembled bacterial genomes (>10 000). The assay includes a new data analysis strategy as well as a general DNA extraction protocol for both Gram-negative and Gram-positive bacteria. We demonstrate that the assay is capable of identifying bacteria directly from uncultured clinical urine samples, as well as in mixtures, with the potential to be discriminative even at the subspecies level. We foresee that the assay has applications both within research labs and in clinical settings, where the time-consuming step of cultivation can be minimized or even completely avoided.Wildfires are an important source of nitrous acid (HONO), a photolabile radical precursor, yet in situ measurements and quantification of primary HONO emissions from open wildfires have been scarce. We present airborne observations of HONO within wildfire plumes sampled during the Western Wildfire Experiment for Cloud chemistry, Aerosol absorption and Nitrogen (WE-CAN) campaign. ΔHONO/ΔCO close to the fire locations ranged from 0.7 to 17 pptv ppbv-1 using a maximum enhancement method, with the median similar to previous observations of temperate forest fire plumes. Measured HONO to NOx enhancement ratios were generally factors of 2, or higher, at early plume ages than previous studies. Enhancement ratios scale with modified combustion efficiency and certain nitrogenous trace gases, which may be useful to estimate HONO release when HONO observations are lacking or plumes have photochemical exposures exceeding an hour as emitted HONO is rapidly photolyzed. We find that HONO photolysis is the dominant contributor to hydrogen oxide radicals (HOx = OH + HO2) in early stage ( less then 3 h) wildfire plume evolution.