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Plasmonic materials can generate strong electromagnetic fields to boost the Raman scattering of surrounding molecules, known as surface-enhanced Raman scattering. However, these electromagnetic fields are heterogeneous, with only molecules located at the 'hotspots', which account for ≈ 1% of the surface area, experiencing efficient enhancement. Herein, we propose patterned plasmonic trimers, consisting of a pair of plasmonic dimers at the bilateral sides and a trap particle positioned in between, to address this challenge. The trimer configuration selectively directs probe molecules to the central traps where 'hotspots' are located through chemical affinity, ensuring a precise spatial overlap between the probes and the location of maximum field enhancement. We investigate the Raman enhancement of the Au@Al2O3-Au-Au@Al2O3 trimers, achieving a detection limit of 10−14 M of 4-methylbenzenethiol, 4-mercaptopyridine, and 4-aminothiophenol. Moreover, single-molecule SERS sensitivity is demonstrated by a bi-analyte method. Benefiting from this sensitivity, our approach is employed for the early detection of lung tumors using fresh tissues. Our findings suggest that this approach is sensitive to adenocarcinoma but not to squamous carcinoma or benign cases, offering insights into the differentiation between lung tumor subtypes. SERS spectroscopy critically relies on the accumulation of analyte molecules in electromagnetic 'hotspots'. Here, the authors demonstrate plasmonic trimers with central particles that act as chemical traps, enabling the subtyping of lung tumors using fresh tissue samples. [ABSTRACT FROM AUTHOR]

The impacts of enhanced nitrogen (N) deposition on the global forest carbon (C) sink and other ecosystem services may depend on whether N is deposited in reduced (mainly as ammonium) or oxidized forms (mainly as nitrate) and the subsequent fate of each. However, the fates of the two key reactive N forms and their contributions to forest C sinks are unclear. Here, we analyze results from 13 ecosystem-scale paired 15N-labelling experiments in temperate, subtropical, and tropical forests. Results show that total ecosystem N retention is similar for ammonium and nitrate, but plants take up more labelled nitrate ( 20 15 25 %) ( mean minimum maximum ) than ammonium ( 12 8 16 %) while soils retain more ammonium ( 57 49 65 %) than nitrate ( 46 32 59 %). We estimate that the N deposition-induced C sink in forests in the 2010s is 0.72 0.49 0.96 Pg C yr−1, higher than previous estimates because of a larger role for oxidized N and greater rates of global N deposition. A study using paired 15N tracers shows atmospheric N deposited in oxidized form is more likely retained by trees, while the reduced form is retained in soil. The authors argue that this is a greater contribution of deposited N to the global forest C sink than previously reported. [ABSTRACT FROM AUTHOR]

Tropical forests play an important role in carbon cycle. However, the temporal and spatial variation in soil carbon dioxide (CO) emission of tropical forest remains uncertain, especially near the Tropic of Cancer. In this research, we studied the annual soil CO fluxes from three tropical montane rainforests on the Hainan Island of China (pristine montane rainforest, PF; secondary montane rainforest, SF; and Podocarpus imbricatus plantation, PP). The results showed a lower annual average soil CO flux as 6.85 ± 0.52 Mg C-CO ha (9.17 Mg C-CO ha in the wet season and 4.50 Mg C-CO ha in the dry season). The CO fluxes exhibited obviously seasonal variation during the study period. Among the three forest types, PF had the highest average CO flux rate of 317.77 ± 147.71 mg CO m h (433.08 mg CO m h in the wet season and 202.47 mg CO m h in the dry season), followed by PP of 286.84 ± 137.48 mg CO m h (367.12 mg CO m h in the wet season and 206.56 mg CO m h in the dry season) and SF of 255.09 ± 155.26 mg CO m h (351.48 mg CO m h in the wet season and 155.71 mg CO m h in the dry season). We found between CO fluxes and soil temperature a highly significant linear relation ( P < 0.01) at 5 cm depth and a highly significant exponential correlation ( P < 0.01) at 10 cm depth for all three forest types; a significant linear relation ( P < 0.05) between CO fluxes and soil moisture content was found for SF and PF, but not for PP ( P > 0.05). The CO flux was significantly correlated ( P < 0.05) with water-filled pore space only for PF. In conclusion, our results suggested soil CO fluxes in the three forest types that exhibit obviously spatial and temporal variation, and the temperature is the major factor affecting soil CO fluxes from this region. [ABSTRACT FROM AUTHOR]

Purpose: Stable vaccines with long shelf lives and reduced dependency on the cold chain are ideal for stockpiling and rapid deployment during public emergencies, including pandemics. Spray drying is a low-cost process that has potential to produce vaccines stable at a wide range of temperatures. Our aim was to develop a stable formulation of a recombinant H1N1 influenza hemagglutinin vaccine candidate and take it to pilot-scale spray-drying production. Methods: Eight formulations containing different excipients were produced and assayed for antigen stability, powder characteristics, and immunogenicity after storage at a range of temperatures, resulting in the identification of four promising candidates. A pilot-scale spray-drying process was then developed for further testing of one formulation. Results: The pilot-scale process was used to reproducibly manufacture three batches of the selected formulation with yields >90%. All batches had stable physical properties and in vitro potency for 6 months at temperatures from −20°C to +50°C. Formulations stored for 3 months elicited immunogenic responses in mice equivalent to a frozen lot of bulk vaccine used as a stability control. Conclusions: This study demonstrates the feasibility of stabilizing subunit vaccines using a spray-drying process and the suitability of the process for manufacturing a candidate product. [ABSTRACT FROM AUTHOR]

Biometric inventories for 25 years, from 1983 to 2005, indicated that the Jianfengling tropical mountain rain forest in Hainan, China, was either a source or a modest sink of carbon. Overall, this forest was a small carbon sink with an accumulation rate of (0.56±0.22) Mg C hayr, integrated from the long-term measurement data of two plots (P9201 and P8302). These findings were similar to those for African and American rain forests ((0.62±0.23) Mg C hayr). The carbon density varied between (201.43±29.38) Mg C ha and (229.16±39.2) Mg C ha, and averaged (214.17±32.42) Mg C ha for plot P9201. Plot P8302, however, varied between (223.95±45.92) Mg C ha and (254.85±48.86) Mg C ha, and averaged (243.35±47.64) Mg C ha. Quadratic relationships were found between the strength of carbon sequestration and heavy rainstorms and dry months. Precipitation and evapotranspiration are two major factors controlling carbon sequestration in the tropical mountain rain forest. [ABSTRACT FROM AUTHOR]

Twenty-three sample plots dominated by Vatica mangachapoi at various elevations in the tropical lowland rainforest in the Jianfengling National Nature Reserve of Hainan Island were established. The interspecific association among the 32 dominant species was analyzed and the division of ecological species groups and functional groups are discussed. The results showed that these dominant populations had an overall positive interspecific association. The species pairs with significant, positive association accounted for only about 10% of the total 496 species pairs. Most of the other species pairs showed weak association or non-association, i.e., the dominant populations investigated had relatively independent distributions. The 32 dominant species were divided into four ecological species groups and ten functional groups according to their interspecific association coefficients, based on a cluster analysis of the species. Recognition characteristics of the ten functional groups are proposed. [ABSTRACT FROM AUTHOR]

Describes epidermal powder immunization (EI) which effectively delivers powdered vaccines to the epidermis by using a helium-powered, needle free PowderJect system. Comparison between EI and needle injection; Challenge experiments; Immunogenicity of influenza vaccine.