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1.
Microb Pathog ; : 104061, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32061916

RESUMO

To compare different nanoparticle-based nasal vaccines against foot-and-mouth disease (FMD), chitosan (CS)-coated poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) (CS/PLGA-NPs) and amino-functionalized mesoporous silica nanoparticles (Am/MSNs) loaded with FMDV recombinant plasmid (pP12A3C/IFN-CS/PLGA-NPs and pP12A3C/IFN-Am/MS-NPs) were used to induce mucosal and systemic immune responses in guinea pigs via intranasal delivery. Simultaneously, CpG oligodeoxy nucleotides (ODNs) as a vaccine adjuvant were encapsulated in chitosan-coated poly (lactic-co-glycolic acid) nanoparticles (CpG-CS/PLGA-NPs). The pP12A3C/IFN-CS/PLGA-NPs and CpG-CS/PLGA-NPs generated displayed good morphology, high stability, mean diameters of 500 and 400 nm and encapsulation efficiencies of 83.8% and 88.4%, respectively. Data from the in vitro release assay showed that plasmid and CpG were sustainably released from nanoparticles (up to 66.73% and 64%, respectively, of the total amount loaded). Guinea pigs immunized with pP12A3C/IFN-CS/PLGA-NPs + CpG-CS/PLGA-NPs showed markedly higher mucosal, cellular and humoral immune responses than those administered pP12A3C/IFN-CS/PLGA-NPs or naked plasmid vaccine alone. FMDV-specific secretory immunoglobulin A (sIgA) antibodies in nasal washes were initially detected at 3 days post-vaccination with CS/PLGA-NPs loaded with plasmid. Guinea pigs immunized with pP12A3C/IFN-CS/PLGA-NPs also displayed higher cellular and humoral immune responses than pP12A3C-CS/PLGA-NPs and naked plasmid vaccine alone. FMDV-specific immunoglobulin G (IgG) antibodies in serum were initially detected at 5 days post-vaccination (intramuscularly) with the naked plasmid. Finally, challenge experiments 42 days post-vaccine revealed 100% protection in guinea pigs immunized with pP12A3C/IFN-CS/PLGA-NPs + CpG-CS/PLGA-NPs and pP12A3C/IFN-CS/PLGA-NPs. However, plasmid DNA was burst released from pP12A3C/IFN-Am/MS-NPs. Our attempts to use pP12A3C/IFN-Am/MS-NPs to immunize guinea pigs failed to induce immune responses. In conclusion, CpG and IFN-α adjuvant based FMD vaccines elicit protection in guinea pigs. Moreover, CS-coated PLGA NPs present an efficient and safe mucosal immune delivery system for FMDV DNA vaccine. Data from the current study provide a foundation for understanding and further evaluating protective immune responses in pigs.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32043867

RESUMO

Over the last decade, lithium-sulfur (Li-S) batteries have been thought of as promising alternatives for the new generation of the battery systems. Although the Li-S batteries possess high theoretical energy density (2600 Wh kg-1) and capacity (1675 mAh g-1), the problems of poor electron and ion conduction, volumetric expansion and sulfur immobilization greatly impede the wide applicability of Li-S batteries. Herein, a defect-rich multi-shelled Co3O4 microsphere structure doped with Fe was synthesized via a one-step hydrothermal method and a subsequent thermal treatment. The unique multi-shelled structure provides multiple spatial confinements for lithium polysulfides (LiPs) trapping and buffers the volume variation during cycling. Moreover, the rich oxygen-defect designed by controllable Fe doping can provide numerous catalytic sites for polysulfide redox reactions. Attributed to the synergistic effect of structural design and oxygen-defect fabrication, the sulfur composite electrode delivers a notable cycle performance, presenting a much lower capacity fading of 0.017% per cycle over 1000 cycles at 1 C and excellent rate capability of 571.3 mAh g-1 at 5 C. This work proposes a potential approach for designing transition-metal-oxide (TMO) based multi-shelled hollow structure combined with oxygen-defect, which also offers a new perspective on high-performance Li-S batteries.

4.
Adv Mater ; 32(4): e1904876, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31697001

RESUMO

The shuttling behavior and sluggish conversion kinetics of the intermediate lithium polysulfides (LiPSs) represent the main obstructions to the practical application of lithium-sulfur (Li-S) batteries. Herein, an anion-deficient design of antimony selenide (Sb2 Se3- x ) is developed to establish a multifunctional LiPS barrier toward the inhibition of polysulfide shuttling and enhancement of battery performance. The defect chemistry in the as-developed Sb2 Se3- x promotes the intrinsic conductivity, strengthens the chemical affinity to LiPSs, and catalyzes the sulfur electrochemical conversion, which are verified by a series of computational and experimental results. Attributed to these unique superiorities, the obtained LiPS barrier efficiently promotes and stabilizes the sulfur electrochemistry, thus enabling excellent Li-S battery performance, e.g., outstanding cyclability over 500 cycles at 1.0 C with a minimum capacity fading rate of 0.027% per cycle, a superb rate capability up to 8.0 C, and a high areal capacity of 7.46 mAh cm-2 under raised sulfur loading. This work offers a defect engineering strategy toward fast and durable sulfur electrochemistry, holding great promise in developing practically viable Li-S batteries as well as enlightening the material design of related energy storage and conversion systems.

5.
Extremophiles ; 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31820112

RESUMO

The group Nitriliruptoria, recently classified as a separate class of phylum Actinobacteria, has five members at present, which belong to halophilic or halotolerant Actinobacteria. Here, we sequenced the genomes of Egicoccus halophilus EGI 80432T and Egibacter rhizosphaerae EGI 80759T, and performed a comparative genomics approach to analyze the genomic differences and salt adaptation mechanisms in Nitriliruptoria. Phylogenetic analysis suggested that Euzebya tangerina F10T has a closer phylogenetic relationship to Euzebya rosea DSW09T, while genomic analysis revealed highest genomic similarity with Nitriliruptor alkaliphilus ANL-iso2T and E. halophilus EGI 80432T. Genomic differences of Nitriliruptoria were mainly observed in genome size, gene contents, and the amounts of gene in per functional categories. Furthermore, our analysis also revealed that Nitriliruptoria possess similar synthesis systems of solutes, such as trehalose, glutamine, glutamate, and proline. On the other hand, each member of Nitriliruptoria species possesses specific mechanisms, K+ influx and efflux, betaine and ectoine synthesis, and compatible solutes transport to survive in various high-salt environments.

6.
Biomed Res Int ; 2019: 8530273, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687402

RESUMO

In recent years, many studies have shown that recombinant adenovirus live vector-based vaccines are a promising novel vaccine candidate against virus infection. Therefore, in this study, a new type of recombinant adenovirus expressing the spike (S) protein of porcine epidemic diarrhea virus (PEDV), rAd-PEDV-S, was generated, and its characteristics were determined. Then, its efficacy as a vaccine candidate was evaluated in 4-week-old pigs. The results showed that the S protein could be well expressed at a high level in rAd-PEDV-S-infected cells and that the viral titers could reach 1011 PFU/mL. Further animal experimental results showed that rAd-PEDV-S elicited a significant PEDV-specific humoral immune response after vaccination (P < 0.05). In addition, rAd-PEDV-S provided partial protection for pigs against the highly virulent PEDV challenge. The results presented in this study indicate that the adenovirus vector can be used as a vaccine delivery vector for the development of a PEDV vaccine and is a promising novel vaccine candidate for future prevention and control of porcine epidemic diarrhea (PED), but its efficacy still needs to be improved in the future.

7.
Nanotechnology ; 31(9): 095405, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31726449

RESUMO

Copper sulfide (CuS) is considered a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity and good electrical conductivity. However, the inferior cycle performance and low coulombic efficiency of CuS caused by structure detoriation and degradation and the 'shuttling effect' of polysulfide intermediates are restricting its practical application. In this work, we report a facile method to generate S vacancies (Vs) in CuS nanoflowers by thermal annealing in Ar. The obtained CuS was composited with reduced graphene oxide (rGO) to prepare an anode for LIBs. The existence of vacancy defects in CuS leads to electron delocalization and excitation, which is responsible for the conductivity improvement and fast charge transport kinetics. Meanwhile, the graphene coating layer ensures fast pathways for Li+ ion diffusion and provides strong physical adsorption of the polysulfides. Furthermore, hierarchical CuS spheres composed of ultrathin nanosheets provide large void spaces to accommodate the volume expansion of CuS. The synthesized composite exhibited a high initial discharge capacity of 882 mAh g-1 and demonstrated stable cyclability along with around 99% coulombic efficiency over 100 cycles. The results of this work reveal that Vs-CuS/rGO composites are promising anodes to enhance the performance of next-generation lithium-ion batteries.

8.
J Clin Neurosci ; 70: 20-26, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31630917

RESUMO

Little information is available on associations between different lumbar interbody fusion (LIF) surgeries and postoperative outcomes. The present study aims to comprehensively investigate whether different LIF techniques are associated with postoperative outcomes such as complications and length of hospital stay. The United States Nationwide Inpatient Sample (NIS) was searched for patients diagnosed with recurrent lumbar disc herniation who underwent lumbar interbody fusion (LIF) surgeries between 2005 and 2014. Patients were categorized based on LIF approaches: anterior lumbar interbody fusion (ALIF); lateral lumbar interbody fusion (LLIF); or posterior lumbar interbody fusion/transforaminal lumbar interbody fusion (PLIF/TLIF). A total of 2625 patients were included in this study. After adjusting for age, severity of illness, and comorbidities, patients who received LLIF and PLIF/TLIF approaches had significantly shorter hospital stays than those receiving ALIF (LLIF vs. ALIF, ß = -0.64; PLIF/TLIF vs. ALIF, ß = -0.40). In addition, patients who received LLIF and PLIF/TLIF approaches had significantly lower risk of digestive system complications compared to those receiving ALIF (LLIF vs. ALIF, aOR = 0.25; PLIF/TLIF vs. ALIF, aOR = 0.18). In conclusion, in patients with recurrent lumbar disc herniation, LLIF and PLIF/TLIF approaches are associated with shorter hospital stays and lower risk of digestive system complications than ALIF. However, LIF approaches do not correlate significantly with the risk of postoperative bleeding or nervous system complications.

9.
Glob Chall ; 3(3): 1800027, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31565365

RESUMO

Atomically modified graphitic carbon nitride quantum dots (QDs), characterized by strongly increased reactivity and stability, are developed. These are deposited on arrays of TiO2 nanopillars used as a photoanode for the photoelectrochemical water splitting. This photoanode shows excellent stability, with 111 h of continuous work without any performance loss, which outperforms the best-reported results by a factor of 10. Remarkably, our photoanode produces hydrogen even at zero bias. The excellent performance is attributed to the enhancement of photoabsorption, as well as to the promotion of charge separation between TiO2 nanopillars and the QDs.

10.
Beilstein J Nanotechnol ; 10: 1726-1736, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31501744

RESUMO

Lithium-sulfur batteries render a high energy density but suffer from poor cyclic performance due to the dissolution of intermediate polysulfides. Herein, a lightweight nanoporous TiO2 and graphene oxide (GO) composite is prepared and utilized as an interlayer between a Li anode and a sulfur cathode to suppress the polysulfide migration and improve the electrochemical performance of Li/S batteries. The interlayer can capture the polysulfides due to the presence of oxygen functional groups and formation of chemical bonds. The hierarchically porous TiO2 nanoparticles are tightly wrapped in GO sheets and facilitate the polysulfide storage and chemical absorption. The excellent adhesion between TiO2 nanoparticles and GO sheets resulted in enhanced conductivity, which is highly desirable for an efficient electron transfer process. The Li/S battery with a TiO2/GO-coated separator exhibited a high initial discharge capacity of 1102.8 mAh g-1 and a 100th cycle capacity of 843.4 mAh g-1, which corresponds to a capacity retention of 76.48% at a current rate of 0.2 C. Moreover, the Li/S battery with the TiO2/GO-coated separator showed superior cyclic performance and excellent rate capability, which shows the promise of the TiO2/GO composite in next-generation Li/S batteries.

11.
Nanomaterials (Basel) ; 9(9)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491960

RESUMO

In this work, black phosphorus quantum dots (BPQDs) were decorated on hexagonal ZnIn2S4 flower-like microspheres to form zero-dimensional/two-dimensional (0D/2D) structures. Interface interactions between the BPQDs and ZnIn2S4 resulted in optimum effective charge transfer, thereby improving the photocatalytic performance of the material. Thus, the 0.2% BPQD-ZnIn2S4 sample showed 30% higher H2 evolution rates compared to pure ZnIn2S4. This study provides a simple route for the synthesis of photocatalysts. The results obtained herein can pave the way for designing effective catalysts for solar-to-chemical energy conversion and feasible approaches to obtain cheap, clean, and efficient photocatalysts.

12.
Viruses ; 11(8)2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31394868

RESUMO

Tumor suppressor protein p53 (p53) is a master transcription factor that plays key roles in cell cycle arrest, apoptosis, senescence, and metabolism, as well as regulation of innate immunity during virus infection. In order to facilitate their replication and spreading, viruses have evolved to manipulate p53 function through different strategies, with some requiring active p53 while others demand reduction/inhibition of p53 activity. However, there are no clear-cut reports about the roles of p53 during the infection of foot-and-mouth disease virus (FMDV), the causative agent of a highly contagious foot-and-mouth disease (FMD) of cloven-hoofed animals. Here we showed that p53 level was dynamically regulated during FMDV infection, being degraded at the early infection stage but recovered to the basal level at the late stage. Cells depleted of p53 showed inhibited FMDV replication and enhanced expression of the immune-related genes, whereas overexpression of p53 didn't affect the viral replication. Viral challenge assay with p53 knockout mice obtained similar results, with viral load decreased, histopathological changes alleviated, and lifespan extended in the p53 knockout mice. Together, these data demonstrate that basal level p53 is required for efficient FMDV replication by suppressing the innate immunity.

13.
Mol Immunol ; 114: 226-232, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31386979

RESUMO

Foot and mouth disease virus (FMDV), a member of family Picornaviridae, belongs to the genus Aphthovirus, which causes foot and mouth disease (FMD), a highly transmissible disease that affects cloven-hoof animals. In spite of the fact that efficient vaccines are available, effective antiviral molecules for FMD are needed to reduce viral infection during early stages of infection. In this study, merimepodib was found to efficiently inhibit FMDV replication in a dose-dependent manner. The 50% inhibitory concentration (IC50) of merimepodib antiviral activity against two distinct FMDV strains (O/MYA98/BY/2010 and A/GD/MM/CHA/2013) was estimated to be 7.859 and 2.876 µM, respectively, while the 50% cytotoxic concentration (CC50) of merimepodib was found to be 47.74 µM. Furthermore, treatment with 30 µg merimepodib efficiently prolonged the survival time of suckling mice infected with FMDV. Taken together, these results suggested that merimepodib has the potential to be a novel antiviral agent against FMDV.


Assuntos
Antivirais/farmacologia , Carbamatos/farmacologia , Vírus da Febre Aftosa/efeitos dos fármacos , Febre Aftosa/tratamento farmacológico , Compostos de Fenilureia/farmacologia , Animais , Linhagem Celular , Camundongos , Suínos , Vacinas Virais/farmacologia , Replicação Viral/efeitos dos fármacos
14.
Appl Microbiol Biotechnol ; 103(19): 8075-8086, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463546

RESUMO

Foot-and-mouth disease virus (FMDV) has led to serious losses in the farming industry worldwide, particularly in cattle and swine. In developing countries, the control and eradication of FMD rely upon vaccination, in which the inactivated vaccine is predominant. In the preparation of inactivated vaccine, a series of purification methods were used to remove non-structural proteins (NSPs). It is necessary to develop a quantitative detection method of residual NSP and confirm a threshold value for the evaluation of the vaccine. Meanwhile, it is also important to develop a sensitive and rapid diagnostic method to distinguish infected animals from vaccinated animals (DIVA). In this study, three monoclonal antibodies (MAbs) against NSP 3ABC, designated 2G5, 9E2, and 1E10, were used. Subsequently, a series of overlapping peptides were expressed using a prokaryotic expression system to determine the minimal epitopes identified by the MAbs. Three linear B cell epitopes (BCEs), "92EYIEKA97" "23EGPYAGPLE31" and "209EPHH212", were identified by MAbs 2G5, 9E2, and 1E10, respectively. Alanine-scanning mutagenesis analysis confirmed the critical amino acid in these epitopes. The epitope "92EYIEKA97" is located in 3A, which is deleted in some natural deletion mutants that result in a change in virus tropism. MAb 9E2 that identified the epitope "23EGPYAGPLE31" reacted with 3B1 and 3B2, but did not react with 3B3. In combination with sequence alignment analysis, the epitope "23EGPYAGPLE31" is highly conserved among different FMDV isolates. Preliminary screening using the known positive and negative sera indicated the MAb 9E2 has the potential for the development of a diagnostic method for DIVA. The residual NSP in inactivated vaccines can be detected using 9E2-HRP, which indicated the MAb 9E2 is able to evaluate inactivated vaccines. The four-amino acid epitope is the first reported to date that is recognized by 1E10. These results provide valuable insight into the diagnosis of DIVA and the NSP residual evaluation in inactivated vaccines.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Mapeamento de Epitopos , Epitopos de Linfócito B/imunologia , Vírus da Febre Aftosa/imunologia , Proteínas não Estruturais Virais/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antivirais/isolamento & purificação , Camundongos
15.
Microb Pathog ; 135: 103638, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31326561

RESUMO

Recently, amiloride was shown to potently suppress Coxsackievirus B3 (CVB3) replication. In the current study, we investigated whether amiloride could also exhibit antiviral activity against foot-and-mouth disease virus (FMDV), which belongs to the same family (Picornaviridae) as CVB3. We found that amiloride exerted antiviral activity in a dose-dependent manner against two strains of FMDV in IBRS-2 cells, with slight cytotoxicity at 1000 µM. Besides, amiloride did not inhibit the attachment and entry of FMDV in IBRS-2 cells, but prevented early viral replication. These data implied that amiloride could be a promising candidate for further research as a potential antiviral drug against FMDV infection.


Assuntos
Amilorida/farmacologia , Antivirais/farmacologia , Vírus da Febre Aftosa/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular , Replicação do DNA/efeitos dos fármacos , Febre Aftosa/virologia , Humanos , RNA Mensageiro/metabolismo , Proteínas Virais
16.
J Med Virol ; 91(12): 2142-2152, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31347713

RESUMO

Recently, many countries, including China, have experienced a series of type A and O foot-and-mouth disease virus (FMDV) epidemics, causing serious economic losses. Although concerns about the safety of inactivated FMD vaccines have been raised, the development of a safe and effective subunit vaccine is necessary. We constructed two chimeric virus-like particles (VLPs; rHBc/AO and rHBc/AOT VLPs) displaying tandem repeats of B cell epitopes (VP1 residue 134-161 and 200-213) derived from type A and O FMDV and one T cell epitope (3 A residue 21-35) using the truncated hepatitis B virus core (HBc) carrier. Our results indicate that the chimeric HBc can self-assemble into VLPs with these FMDV epitopes displayed on the surface. Immunization with the chimeric VLPs induced specific IgG and neutralization antibodies against type A and O FMDV in mice. Compared with the commercial type A/O FMDV bivalent inactivated vaccine, rHBc/AO and rHBc/AOT VLPs significantly stimulated the production of Th1 type cytokines (IFN-γ and IL-2), whereas Th2 cytokine production (IL-4 and IL-10) was decreased. Compared with rHBc/AO, rHBc/AOT induced increased Th2 cytokine and specific IgG production. These results demonstrate that the VLPs constructed in the current study induced both humoral and cellular immune responses and may represent potential bivalent VLP vaccines targeting both FMDV type A and O strains.

17.
Sci Total Environ ; 690: 973-990, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302561

RESUMO

The paddy rice fields act as an important anthropogenic source of methane (CH4) to the atmosphere. The study of pattern, magnitude, and environmental controls of CH4 emissions are still insufficient due to limited measurements and understand of underlying drivers for variations of CH4 fluxes at different temporal scales. In this study, CH4 fluxes from a rice-wheat rotation agroecosystem in eastern China were continuously measured using the eddy covariance technique. The diurnal and seasonal variations of CH4 flux and potential controlling factors in 2016 were analyzed using wavelet coherence, conditional Granger causality, correlation analysis and path analysis methods. CH4 fluxes showed distinguishable diurnal variations with single peaks during 13: 00-16: 00 local time. At the diurnal timescale, gross primary productivity (GPP) regulates CH4 fluxes after accounting for the effects of latent heat flux (LE), air temperature (TA), and soil temperature (TS) on CH4 fluxes. LE mirrored the diurnal pattern of CH4 fluxes when the effects of TA and TS on CH4 fluxes were considered. Daily CH4 fluxes exhibited large seasonal variations, with the largest daily CH4 flux of 1191.78 mg C-CH4 m-2 d-1 on 29 July 2016. The daily CH4 fluxes were continuously low in the growing season of wheat, and sharply increased from very low values in late June to peaks in late July and early August, and then gradually decreased to low values at the end of the rice growing season in late November and early December. Correlation analysis and path analysis showed that seasonal variations of soil temperature, air temperature, and GPP had strong effects on daily CH4 fluxes during pre-panicle initiation of the rice growing season, while soil temperature and leaf area index (LAI) had very strong effects on daily CH4 fluxes during the post-panicle initiation stage. The total of CH4 fluxes from the rice-wheat rotation agroecosystem into the atmosphere amounted to 58.08 ±â€¯9.87 g C m-2 in 2016, and the annual net carbon (C) budget and greenhouse gas (GHG) budget were 163.50 ±â€¯9.87 g C m-2 and 2322.53 ±â€¯329.00 g CO2eq m-2, respectively. This study represents a comprehensive assessment of fluxes and drivers of CH4 from a rice-wheat rotation agroecosystem at different timescales. Additionally, the consecutive data of CH4 emission in this region will also useful for model calibration and validation.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Metano/análise , Agricultura , China , Gases de Efeito Estufa/análise , Oryza , Estações do Ano , Triticum
18.
Sci Total Environ ; 690: 584-595, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31301499

RESUMO

Water use efficiency (WUE) is a central parameter for linking carbon and water exchange processes in terrestrial ecosystems. The Beijing-Tianjin Sand Source Region (BTSSR) in China has undergone tremendous vegetation restoration and climate change. Understanding the WUE responses to climate change and human activity and their relative contributions to the trends and inter-annual variations (IAVs) in WUE is necessary to improve water use efficiency and strengthen water resource management. The evapotranspiration (ET) dataset based on the model tree ensemble (MTE) algorithm which was a machine learning approach using flux-tower ET measurements and the GLASS GPP dataset, as well as the variance decomposition method, were used to analyze the spatiotemporal changes in water use efficiency and inherent water use efficiency (IWUE) and the impacts of climate change and human activities. The results showed that the annual WUE and IWUE exhibited significantly increase in most regions of the BTSSR. The trend of human activity played the most important role in the increases of WUE and IWUE, with relative contributions of 88.2% and 85.9%, respectively, followed by the IAV of human activity for WUE (6.1%) and the trend of climate change (8.7%) for IWUE. The contribution of IAV to climate change was relatively small. Moreover, WUE and IWUE were all positively correlated with precipitation and temperature in most regions. Our results indicated that ecological restoration projects had significantly improved water use efficiency in BTSSR and may decrease the water burden in the BTSSR.


Assuntos
Mudança Climática , Ecossistema , Abastecimento de Água/estatística & dados numéricos , China , Atividades Humanas , Humanos , Recursos Hídricos/provisão & distribução
19.
Virology ; 535: 162-170, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31306911

RESUMO

MicroRNAs (miRNAs) play important regulatory roles during interactions between virus pathogens and host cells, but whether and how they work in the case of foot-and-mouth disease virus (FMDV) is less understood. Based on a microarray-based miRNA profiling in the porcine kidney cell line PK-15, we identified 36 differentially expressed host miRNAs at the early stage of FMDV infection, among which miR-1307 was significantly induced. Functional characterization demonstrated that miR-1307 attenuated FMDV replication. Further experiments proved that miR-1307 specifically promoted the degradation of the viral structural protein VP3 indirectly through proteasome pathway. Moreover, innate immune signaling was activated and expression of immune responsive genes was significantly enhanced in the miR-1307-overexpressing clones. Together, our data demonstrated that miR-1307 suppresses FMDV replication by destabilizing VP3 and enhancing host immune response. Importantly, subcutaneous injection of miR-1307 agomir delayed the FMDV-induced lethality in suckling mice, exhibiting its therapeutic potential to control foot-and-mouth disease (FMD).

20.
Sensors (Basel) ; 19(13)2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288443

RESUMO

Solar-induced chlorophyll fluorescence (SIF) is regarded as a proxy for photosynthesis in terrestrial vegetation. Tower-based long-term observations of SIF are very important for gaining further insight into the ecosystem-specific seasonal dynamics of photosynthetic activity, including gross primary production (GPP). Here, we present the design and operation of the tower-based automated SIF measurement (SIFSpec) system. This system was developed with the aim of obtaining synchronous SIF observations and flux measurements across different terrestrial ecosystems, as well as to validate the increasing number of satellite SIF products using in situ measurements. Details of the system components, instrument installation, calibration, data collection, and processing are introduced. Atmospheric correction is also included in the data processing chain, which is important, but usually ignored for tower-based SIF measurements. Continuous measurements made across two growing cycles over maize at a Daman (DM) flux site (in Gansu province, China) demonstrate the reliable performance of SIF as an indicator for tracking the diurnal variations in photosynthetically active radiation (PAR) and seasonal variations in GPP. For the O2-A band in particular, a high correlation coefficient value of 0.81 is found between the SIF and seasonal variations of GPP. It is thus concluded that, in coordination with continuous eddy covariance (EC) flux measurements, automated and continuous SIF observations can provide a reliable approach for understanding the photosynthetic activity of the terrestrial ecosystem, and are also able to bridge the link between ground-based optical measurements and airborne or satellite remote sensing data.


Assuntos
Clorofila/análise , Fotossíntese , Tecnologia de Sensoriamento Remoto/instrumentação , Tecnologia de Sensoriamento Remoto/métodos , Calibragem , China , Ritmo Circadiano , Produtos Agrícolas , Desenho de Equipamento , Fluorescência , Florestas , Oxigênio/análise , Estações do Ano , Luz Solar , Temperatura Ambiente , Zea mays
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