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Plasmon-induced oxidation has conventionally been attributed to the transfer of plasmonic hot holes. However, this theoretical framework encounters challenges in elucidating the latest experimental findings, such as enhanced catalytic efficiency under uncoupled irradiation conditions and superior oxidizability of silver nanoparticles. Herein, we employ liquid surface-enhanced Raman spectroscopy (SERS) as a real-time and in situ tool to explore the oxidation mechanisms in plasmonic catalysis, taking the decarboxylation of p-mercaptobenzoic acid (PMBA) as a case study. Our findings suggest that the plasmon-induced oxidation is driven by reactive oxygen species (ROS) rather than hot holes, holding true for both the Au and Ag nanoparticles. Subsequent investigations suggest that plasmon-induced ROS may arise from hot carriers or energy transfer mechanisms, exhibiting selectivity under different experimental conditions. The observations were substantiated by investigating the cleavage of the carbon-boron bonds. Furthermore, the underlying mechanisms were clarified by energy level theories, advancing our understanding of plasmonic catalysis.
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Deep venous thrombosis (DVT) is the third most common cardiovascular disease. Its clinical therapeutic effect is unsatisfactory due to the high rate of postthrombotic syndrome. Several studies have demonstrated the involvement of miRNAs in DVT. Therefore, we identified differentially expressed miRNAs in patients with DVT and explored their effects and underlying mechanism on endothelial cell (EC) injury.Differentially expressed miRNAs were identified via microRNA sequencing and verified using real-time quantitative PCR. The biological function of miR-181c-5p in human umbilical vein endothelial cell (HUVEC) injury stimulated by oxidized low-density lipoprotein (ox-LDL) was investigated. The target gene of miR-181c-5p was analyzed using bioinformatics and verified via dual-luciferase reporter assay.miRNA sequencing showed that miR-181c-5p was downregulated in the peripheral blood of patients with DVT. Furthermore, miR-181c-5p had a high clinical diagnostic value for DVT by receiver operating characteristic curve analysis. An in vitro cell model of EC injury, miR-181c-5p, was repressed in ox-LDL-treated HUVECs. Enhancing miR-181c-5p expression could alleviate the inhibition cell viability, cell apoptosis, raising ROS and MDA production, the reducing SOD level, and the elevated levels of thrombosis-related factor, ET-1 and vWF induced by ox-LDL. Further analysis revealed that FBJ osteosarcoma oncogene (FOS) is a target of miR-181c-5p and could antagonize the protective role of miR-181c-5p in ox-LDL-induced HUVEC injury.Our research demonstrated that miR-181c-5p could attenuate ox-LDL-induced EC injury and thrombosis-related factor expression by negatively regulating FOS. These findings suggest that the miR-181c-5p/FOS axis is a promising therapeutic target for DVT.
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MicroARNs , Trombosis , Trombosis de la Vena , Humanos , Apoptosis/genética , Proliferación Celular , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Lipoproteínas LDL/farmacología , Lipoproteínas LDL/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Trombosis/metabolismo , Trombosis de la Vena/genéticaRESUMEN
The effects of nitrogen (N) deposition on forests largely depend on its fate after entering the ecosystem. While several studies have addressed the forest fate of N deposition using 15 N tracers, the long-term fate and redistribution of deposited N in tropical forests remains unknown. Here, we applied 15 N tracers to examine the fates of deposited ammonium ( NH 4 + ) and nitrate ( NO 3 - ) separately over 3 years in a primary and a secondary tropical montane forest in southern China. Three months after 15 N tracer addition, over 60% of 15 N was retained in the forests studied. Total ecosystem retention did not change over the study period, but between 3 months and 3 years following deposition 15 N recovery in plants increased from 10% to 19% and 13% to 22% in the primary and secondary forests, respectively, while 15 N recovery in the organic soil declined from 16% to 2% and 9% to 2%. Mineral soil retained 50% and 35% of 15 N in the primary and secondary forests, with retention being stable over time. The total ecosystem retention of the two N forms did not differ significantly, but plants retained more 15 NO 3 - than 15 NH 4 + and the organic soil more 15 NH 4 + than NO 3 - . Mineral soil did not differ in 15 NH 4 + and 15 NO 3 - retention. Compared to temperate forests, proportionally more 15 N was distributed to mineral soil and plants in these tropical forests. Overall, our results suggest that atmospherically deposited NH 4 + and NO 3 - is rapidly lost in the short term (months) but thereafter securely retained within the ecosystem, with retained N becoming redistributed to plants and mineral soil from the organic soil. This long-term N retention may benefit tropical montane forest growth and enhance ecosystem carbon sequestration.
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Ecosistema , Nitrógeno , China , Bosques , Suelo , ÁrbolesRESUMEN
Histone demethylases are promising therapeutic targets as they play fundamental roles for survival of Mixed lineage leukemia rearranged acute leukemia (MLLr AL). Here we focused on the catalytic Jumonji domain of histone H3 lysine 9 (H3K9) demethylase JMJD1C to screen for potential small molecular modulators from 149,519 natural products and 33,765 Chinese medicine components via virtual screening. JMJD1C Jumonji domain inhibitor 4 (JDI-4) and JDI-12 that share a common structural backbone were detected within the top 15 compounds. Surface plasmon resonance analysis showed that JDI-4 and JDI-12 bind to JMJD1C and its family homolog KDM3B with modest affinity. In vitro demethylation assays showed that JDI-4 can reverse the H3K9 demethylation conferred by KDM3B. In vivo demethylation assays indicated that JDI-4 and JDI-12 could induce the global increase of H3K9 methylation. Cell proliferation and colony formation assays documented that JDI-4 and JDI-12 kill MLLr AL and other malignant hematopoietic cells, but not leukemia cells resistant to JMJD1C depletion or cord blood cells. Furthermore, JDI-16, among multiple compounds structurally akin to JDI-4/JDI-12, exhibits superior killing activities against malignant hematopoietic cells compared to JDI-4/JDI-12. Mechanistically, JDI-16 not only induces apoptosis but also differentiation of MLLr AL cells. RNA sequencing and quantitative PCR showed that JDI-16 induced gene expression associated with cell metabolism; targeted metabolomics revealed that JDI-16 downregulates lactic acids, NADP+ and other metabolites. Moreover, JDI-16 collaborates with all-trans retinoic acid to repress MLLr AML cells. In summary, we identified bona fide JMJD1C inhibitors that induce preferential death of MLLr AL cells.
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Antineoplásicos/farmacología , Histona Demetilasas con Dominio de Jumonji/antagonistas & inhibidores , Leucemia Bifenotípica Aguda/tratamiento farmacológico , Oxidorreductasas N-Desmetilantes/antagonistas & inhibidores , Adulto , Anciano , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Médula Ósea/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Desmetilación del ADN/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Sinergismo Farmacológico , Femenino , Histonas/metabolismo , Humanos , Histona Demetilasas con Dominio de Jumonji/química , Histona Demetilasas con Dominio de Jumonji/metabolismo , Leucemia Bifenotípica Aguda/patología , Masculino , Persona de Mediana Edad , Simulación del Acoplamiento Molecular , Oxidorreductasas N-Desmetilantes/química , Oxidorreductasas N-Desmetilantes/metabolismo , Dominios Proteicos , Relación Estructura-Actividad , Resonancia por Plasmón de Superficie , Tretinoina/farmacología , Tretinoina/uso terapéuticoRESUMEN
According to manufacturers, inactivated poliovirus vaccines (IPVs) are freeze sensitive and require storage between 2°C and 8°C, whereas oral poliovirus vaccine requires storage at -20⯰C. Introducing IPV into ongoing immunization services might result in accidental exposure to freezing temperatures and potential loss of vaccine potency. To better understand the effect of freezing IPVs, samples of single-dose vaccine vials from Statens Serum Institut (VeroPol) and multi-dose vaccine vials from Sanofi Pasteur (IPOL) were exposed to freezing temperatures mimicking what a vaccine vial might encounter in the field. D-antigen content was measured to determine the in vitro potency by ELISA. Immunogenicity testing was conducted for a subset of exposed IPVs using the rat model. Freezing VeroPol had no detectable effect on in vitro potency (D-antigen content) in all exposures tested. Freezing of the IPOL vaccine for 7 days at -20⯰C showed statistically significant decreases in D-antigen content by ELISA in poliovirus type 1 (pâ¯<â¯0.0001) and type 3 (pâ¯=â¯0.048). Reduction of poliovirus type 2 potency also approached significance (pâ¯=â¯0.062). The observed loss in D-antigen content did not affect immunogenicity in the rat model. Further work is required to determine the significance of the loss observed and the implications for vaccine handling policies and practices.
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Criopreservación , Congelación , Inmunogenicidad Vacunal , Vacuna Antipolio de Virus Inactivados/inmunología , Animales , Femenino , Ratas , Ratas WistarRESUMEN
Denitrification removes fixed nitrogen (N) from the biosphere, thereby restricting the availability of this key limiting nutrient for terrestrial plant productivity. This microbially driven process has been exceedingly difficult to measure, however, given the large background of nitrogen gas (N2) in the atmosphere and vexing scaling issues associated with heterogeneous soil systems. Here, we use natural abundance of N and oxygen isotopes in nitrate (NO3 (-)) to examine dentrification rates across six forest sites in southern China and central Japan, which span temperate to tropical climates, as well as various stand ages and N deposition regimes. Our multiple stable isotope approach across soil to watershed scales shows that traditional techniques underestimate terrestrial denitrification fluxes by up to 98%, with annual losses of 5.6-30.1 kg of N per hectare via this gaseous pathway. These N export fluxes are up to sixfold higher than NO3 (-) leaching, pointing to widespread dominance of denitrification in removing NO3 (-) from forest ecosystems across a range of conditions. Further, we report that the loss of NO3 (-) to denitrification decreased in comparison to leaching pathways in sites with the highest rates of anthropogenic N deposition.
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Desnitrificación , Ecosistema , Bosques , Microbiota , Nitratos/metabolismoRESUMEN
The recent outbreak of H7N9 influenza virus infections in humans in China has raised concerns about the pandemic potential of this strain. Here, we test the efficacy of H3 stalk-based chimeric hemagglutinin universal influenza virus vaccine constructs to protect against H7N9 challenge in mice. Chimeric hemagglutinin constructs protected from viral challenge in the context of different administration routes as well as with a generic oil-in-water adjuvant similar to formulations licensed for use in humans.
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Subtipo H7N9 del Virus de la Influenza A , Vacunas contra la Influenza/inmunología , Infecciones por Orthomyxoviridae/prevención & control , Adyuvantes Inmunológicos , Animales , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Ratones , Infecciones por Orthomyxoviridae/inmunología , Proteínas Recombinantes de Fusión/genéticaRESUMEN
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.
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Antígenos Virales/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Vacunas contra la Influenza/química , Tecnología Farmacéutica/métodos , Animales , Antígenos Virales/inmunología , Química Farmacéutica/métodos , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Excipientes/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Humanos , Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Ratones , Ratones Endogámicos BALB C , Polvos/química , TemperaturaRESUMEN
The foliar stable N isotope ratio (δ(15)N) can provide integrated information on ecosystem N cycling. Here we present the δ(15)N of plant and soil in four remote typical tropical rainforests (one primary and three secondary) of southern China. We aimed to examine if (1) foliar δ(15)N in the study forests is negative, as observed in other tropical and subtropical sites in eastern Asia; (2) variation in δ(15)N among different species is smaller compared to that in many N-limited temperate and boreal ecosystems; and (3) the primary forest is more N rich than the younger secondary forests and therefore is more (15)N enriched. Our results show that foliar δ(15)N ranged from -5.1 to 1.3 for 39 collected plant species with different growth strategies and mycorrhizal types, and that for 35 species it was negative. Soil NO3 (-) had low δ(15)N (-11.4 to -3.2) and plant NO3 (-) uptake could not explain the negative foliar δ(15)N values (NH4 (+) was dominant in the soil inorganic-N fraction). We suggest that negative values might be caused by isotope fractionation during soil NH4 (+) uptake and mycorrhizal N transfer, and by direct uptake of atmospheric NH3/NH4 (+). The variation in foliar δ(15)N among species (by about 6) was smaller than in many N-limited ecosystems, which is typically about or over 10. The primary forest had a larger N capital in plants than the secondary forests. Foliar δ(15)N and the enrichment factor (foliar δ(15)N minus soil δ(15)N) were higher in the primary forest than in the secondary forests, albeit differences were small, while there was no consistent pattern in soil δ(15)N between primary and secondary forests.
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Ecosistema , Ciclo del Nitrógeno , Isótopos de Nitrógeno/análisis , Suelo/química , Biomasa , China , Micorrizas , Hojas de la Planta/química , Plantas/química , Plantas/microbiología , ÁrbolesRESUMEN
Surface-enhanced Raman scattering (SERS) is renowned for amplifying Raman signals, with electromagnetic mechanism (EM) enhancement arising from localized surface plasmon resonances and chemical mechanism (CM) enhancement as a result of charge transfer interactions. Despite the conventional emphasis on EM as a result of plasmonic effects, recent findings highlight the significance of CM when noble metals appear as smaller entities. However, the threshold size of the noble metal clusters/particles corresponding to the switch in SERS mechanisms is not clear at present. In this work, the VSe2-xOx/Au composites with different Au sizes are employed, in which a clear view of the SERS mechanism switch is observed at the Au size range of 16-21 nm. Our findings not only provide insight into the impact of noble metal size on SERS efficiency but also offer quantitative data to assist researchers in making informed judgments when analyzing SERS mechanisms.
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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.
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Oro , Neoplasias Pulmonares , Nanopartículas del Metal , Espectrometría Raman , Espectrometría Raman/métodos , Neoplasias Pulmonares/diagnóstico , Oro/química , Humanos , Nanopartículas del Metal/química , Compuestos de Sulfhidrilo/química , Compuestos de Anilina/química , Adenocarcinoma/diagnóstico , Límite de Detección , Piridinas/químicaRESUMEN
Tropical forests, where the soils are nitrogen (N) rich but phosphorus (P) poor, have a disproportionate influence on global carbon (C) and N cycling. While N deposition substantially alters soil C and N retention in tropical forests, whether P input can alleviate these N-induced effects by regulating soil microbial functions remains unclear. We investigated soil microbial taxonomy and functional traits in response to 10-year independent and interactive effects of N and P additions in a primary and a secondary tropical forest in Hainan Island. In the primary forest, N addition boosted oligotrophic bacteria and phosphatase and enriched genes responsible for C-, P-mineralization, nitrification and denitrification, suggesting aggravated P limitation while N excess. This might stimulate P excavation via organic matter mineralization, and enhance N losses, thereby increasing soil CO2 and N2O emissions by 86% and 110%, respectively. Phosphorus and NP additions elevated C-mining enzymes activity mainly due to intensified C limitation, causing 82% increase in CO2 emission. In secondary forest, P and NP additions reduced phosphatase activity, enriched fungal copiotrophs and increased microbial biomass, suggesting removal of nutrient deficiencies and stimulation of fungal growth. Meanwhile, soil CO2 emission decreased by 25% and N2O emission declined by 52-82% due to alleviated P acquisition from organic matter decomposition and increased microbial C and N immobilization. Overall, N addition accelerates most microbial processes for C and N release in tropical forests. Long-term P addition increases C and N retention via reducing soil CO2 and N2O emissions in the secondary but not primary forest because of strong C limitation to microbial N immobilization. Further, the seasonal and annual variations in CO2 and N2O emissions should be considered in future studies to test the generalization of these findings and predict and model dynamics in greenhouse gas emissions and C and N cycling.
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Dióxido de Carbono , Suelo , Dióxido de Carbono/farmacología , Dióxido de Carbono/análisis , Microbiología del Suelo , Fósforo , Bosques , Nitrógeno/farmacología , Óxido Nitroso/análisisRESUMEN
Elucidating the effects of atmospheric nitrogen (N) deposition on the photosynthetic capacity of plants is critical to understand forest growth and conservation under global change. However, studies on this topic generally consider only understory N addition, which ignores the effect of canopy interception. In this study, we conducted a field experiment in a subtropical forest to compare the effects of canopy vs. understory N addition on the photosynthetic rate of canopy and understory species. We found that canopy N addition enhanced the photosynthetic rate of canopy species by increasing leaf hydraulic conductivity and shortening the distance of CO2 transportation. In contrast, understory N addition had non-significant effects on the photosynthetic rate of canopy species. Moreover, the photosynthetic rate of understory species was not affected by canopy or understory N addition. Interestingly, changes in hydraulic conductivity contributed more to accelerating the photosynthetic rate than changes in CO2 transport distance. Our results provide important insights into the dissimilar effects of canopy and understory N addition on the photosynthetic rates of species in subtropical forests. Based on our findings, we highlighted the urgent need to consider canopy processes in future studies on N deposition.
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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 ([Formula: see text]%) ([Formula: see text]) than ammonium ([Formula: see text]%) while soils retain more ammonium ([Formula: see text]%) than nitrate ([Formula: see text]%). We estimate that the N deposition-induced C sink in forests in the 2010s is [Formula: see text] Pg C yr-1, higher than previous estimates because of a larger role for oxidized N and greater rates of global N deposition.
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Compuestos de Amonio/análisis , Secuestro de Carbono/fisiología , Restauración y Remediación Ambiental , Bosques , Nitratos/análisis , Árboles/metabolismo , Ambiente , Isótopos de Nitrógeno/química , Óxidos de Nitrógeno/análisis , Suelo/químicaRESUMEN
Understanding the successional process from a disturbed forest to a mature forest is essential for species recovery and conservation initiatives. The resource acquisition and drought tolerance of plants can be instructive to predictions of species abundance and distribution for different forests. However, they have not been adequately tested at different successional stages in karst regions. Here, we selected seven dominant species in an early-succession forest and 17 species in a late-succession forest in a karst region of southwestern China. Resource acquisition-related traits such as hydraulic conductivity and photosynthetic rate, and drought tolerance-related traits, including turgor loss point and wood density, were measured. We found that species in the early-succession forest had a higher hydraulic conductance and photosynthetic rate than those in the late-succession forest, while leaf water potential at turgor loss point and wood density showed nonsignificant differences between the two forests. In addition, we observed a significant negative relationship between photosynthetic rate and drought tolerance in the early-succession forest, which was not identified in late-succession forests. Our study indicates that resource acquisition rather than drought tolerance was the key factor explaining plant distributions in forests at different successional stages in karst regions. We also suggest that the resource acquisition and drought tolerance trade-off hypothesis is not always supported for karst region species. Our study could inform about the design of species replacements in successional forests and provide forest management and restoration guidelines for karst regions.
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An electrochemically regioselective C-H phosphorothiolation of (hetero)arenes with thiocyanate as the S source under ultrasonic irradiation has been developed. The synergistic cooperation of electrooxidation and ultrasonication markedly accelerated the C-H phosphorothiolation reaction. This mechanistically different method is distinguished by its wide substrate scope and transition-metal-free and external-oxidant-free conditions, thus complementing the existing metal-catalyzed or peroxide-mediated protocols for the green synthesis of S-(hetero)aryl phosphorothioates.
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Parenterally administered rotavirus vaccines may overcome the low efficacy observed in resource-poor regions that use live oral formulations. We have reported work on a trivalent nonreplicating rotavirus vaccine (NRRV) for parenteral administration consisting of the recombinant tetanus toxoid P2 CD4 epitope fused to a truncated VP8* fragment (P2-VP8*) for the P[4], P[6], and P[8] serotypes of rotavirus adjuvanted with aluminum. An essential part of developing this vaccine candidate was devising quantification methods for each antigen in the trivalent NRRV in the presence of aluminum adjuvant. This report describes the development of quantitative inhibition enzyme-linked immunosorbent assays (ELISAs) for in vitro antigenicity determination of the adjuvanted trivalent NRRV using serotype-specific monoclonal antibodies (mAbs) against each of the P2-VP8* antigens. Adjuvanted trivalent vaccine samples are titrated and incubated with a constant concentration of specific mAbs against each NRRV P2-VP8* antigen variant. Unbound mAbs are measured by ELISA to indirectly quantify the amount of each antigen present in the trivalent vaccine. Sensitive, specific, and reproducible inhibition ELISAs were developed and qualified for each antigen and used for final product quantification and release testing without desorption of the vaccine antigen.
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Ensayo de Inmunoadsorción Enzimática/métodos , Epítopos de Linfocito T/genética , Péptidos/genética , Proteínas de Unión al ARN/genética , Proteínas Recombinantes de Fusión/genética , Vacunas contra Rotavirus/inmunología , Toxoide Tetánico/genética , Proteínas no Estructurales Virales/genética , Adyuvantes Inmunológicos , Anticuerpos Monoclonales/metabolismo , Humanos , Inmunogenicidad Vacunal , Infusiones Parenterales , Vacunas contra Rotavirus/genéticaRESUMEN
Hainan Tropical Rainforest National Park has the most representative and largest contiguous tropical rainforest in China, which has advantages in exploring the realization mechanism of ecological product value in national parks. Based on the basic framework of "The Technical Guideline on Gross Ecosystem Product (GEP)", we constructed a GEP accounting system in line with the characteristics of tropical rain forest national park, and calculated the GEP of Hainan Tropical Rainforest National Park in 2019. The results showed that the GEP of Hainan Tropical Rainforest National Park in 2019 was 204.513 billion yuan, and the GEP per unit area was 0.046 billion yuan·km-2. Among all the service types, the value of material services was 4.850 billion yuan, accounting for 2.4% of the total GEP in the national park. The ecosystem regulation service value was 168.891 billion yuan, accounting for 82.6%. The value of cultural services was 30.772 billion yuan, accounting for 15.0%. Among different ecosystem types, the unit area value of the tropical rain forest ecosystem represented by mountain rain forest, lowland rain forest, deciduous monsoon forest, and tropical cloud forest was much higher than that of plantation or other ecosystems, indicating the dominant role of tropical rain forest ecosystem in providing ecosystem services. In addition, based on the GEP accounting results of the national park, we put forward relevant suggestions for further exploring the realization path and realization mechanism of ecological product value.
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Ecosistema , Bosque Lluvioso , China , Bosques , Parques RecreativosRESUMEN
Organic waste, the predominant component of global solid waste, has never been higher, resulting in increased landfilling, incineration, and open dumping that releases greenhouse gases and toxins that contribute to global warming and environmental pollution. The need to create and adopt sustainable closed-loop systems for waste reduction and valorization is critical. Using organic waste as a feedstock, gasification and pyrolysis systems can produce biooil, syngas, and thermal energy, while reducing waste mass by as much as 85-95% through conversion into biochar, a valuable byproduct with myriad uses from soil conditioning to bioremediation and carbon sequestration. Here, we present a novel case study detailing the circular economy of gasification biochar in Singapore's Gardens by the Bay. Biochar produced from horticultural waste within the Gardens was tested as a partial peat moss substitute in growing lettuce, pak choi, and pansy, and found to be a viable substitute for peat moss. At low percentages of 20-30% gasification biochar, fresh weight yields for lettuce and pak choi were comparable to or exceeded those of plants grown in pure peat moss. The biochar was also analyzed as a potential additive to concrete, with a 2% biochar mortar compound found to be of suitable strength for non-structural functions, such as sidewalks, ditches, and other civil applications. These results demonstrate the global potential of circular economies based on local biochar creation and on-site use through the valorization of horticultural waste via gasification, generating clean, renewable heat or electricity, and producing a carbon-neutral to -negative byproduct in the form of biochar. They also indicate the potential of scaled-up pyrolysis or gasification systems for a circular economy in waste management.
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Carbón Orgánico , Pirólisis , Singapur , SueloRESUMEN
Biochar, produced as a by-product of pyrolysis/gasification of waste biomass, shows great potential to reduce the environment impact, address the climate change issue, and establish a circular economy model. Despite the promising outlook, the research on the benefits of biochar remains highly debated. This has been attributed to the heterogeneity of biochar itself, with its inherent physical, chemical and biological properties highly influenced by production variables such as feedstock types and treating conditions. Hence, to enable meaningful comparison of results, establishment of an agreed international standard to govern the production of biochar for specific uses is necessary. In this study, we analyzed four key uses of biochar: 1) in agriculture and horticulture, 2) as construction material, 3) as activated carbon, and 4) in anaerobic digestion. Then the guidelines for the properties of biochar, especially for the concentrations of toxic heavy metals, for its environmental friendly application were proposed in the context of Singapore. The international status of the biochar industry code of practice, feedback from Singapore local industry and government agencies, as well as future perspectives for the biochar industry were explained.