Natural ecosystems of the West Liao River basin (WLRB) in northeast China have been damaged by both natural and human factors from the 1990s. Since 2000, China’s Grain-for-Green Program (GFGP) has ...been widely adopted with the aim of improving ecosystem services. An accurate evaluation of the eco-hydrological effects for policy implementation is essential to provide references for further restoration of ecosystem services. This study quantified and characterized the ecosystem services and their trade-offs/synergies using models and statistical methods in the WLRB from 1990 to 2020. Moreover, the impact of key drivers on ecosystem services was evaluated by the difference-in-differences model. Among them, the study mainly investigated how GFGP affects ecosystem services. The results confirmed that the water yield, carbon sequestration, habitat quality, and total ecosystem service of the WLRB decreased in the pre-GFGP period (1990–2000). However, this tendency was reversed in the regions where the GFGP was implemented during the period of 2001–2020. Furthermore, a synergistic relationship was shown among carbon sequestration, soil conservation, and habitat quality. Additionally, there were tradeoffs between water yield and the other three ecosystem services, especially in mountain areas. The GFGP could restore carbon sequestration, habitat quality, and total ecosystem services by 1.3%, 2.1%, and 0.6%, respectively. Nevertheless, GFCP may enlarge the tradeoff and imbalance between water yield and habitat quality. Results highlight the need for the governance of ecosystem protection and suggest natural restoration in the mountain area for maintaining water yield and helping ecosystem restoration. Timely adjustment of the policy implementation areas is the key to improving and balancing multiple ecosystem services in the future.
Chinese plum (
Lindl.) is a nutritionally and economically important stone fruit widely grown around the world. Anthracnose, caused by
spp., is one of the primary biotic stress factors limiting plum ...production. Medicinal plants may harbor rhizospheric or endophytic microorganisms that produce bioactive metabolites that can be used as anthracnose biocontrol agents. Here, 27 bacterial isolates from the medicinal plant
with diverse antagonistic activities against
were screened. Based on morphological, physiological, biochemical, and molecular characterization, 25 of these isolates belong to different species of genus
, one to
, and one more to
. Eight representative strains showed high biocontrol efficacy against plum anthracnose in a pot experiment. In addition, several
isolates showed a broad spectrum of inhibitory activity against a variety of fungal phytopathogens. Analysis of the volatile organic compound profile of these eight representative strains revealed a total of 47 compounds, most of which were ketones, while the others included alkanes, alkenes, alcohols, pyrazines, and phenols. Overall, this study confirmed the potential value of eight bacterial isolates for development as anthracnose biocontrol agents.
The net anthropogenic nitrogen input（NANI） is an important nutrient source that causes eutrophication in water bodies. Understanding the spatio-temporal variation of NANI is important for regional ...environment assessment and management.This paper calculated NANI in the upper Yangtze River basin（YRB）, upstream of the Three Gorges Dam（TGD）, from1990 to 2012, and analyzed its spatio-temporal characteristics. Over the past 23 years of the study, the average annual NANI increased from 3200 kg N km~（-2） to 4931 kg N km~（-2）. The major components were fertilizer N application, atmospheric N deposition,and net food and feed N import. In the northwest high mountainous region with a sparse population, the main component was atmospheric N deposition. Fertilizer N application and net food and feed N import were concentrated in the Chengdu Plain because of the high population density and large areas of farmland. This research found that NANI increased with rapid urbanization and increasing population. The Pearson correlation results illustrated that the spatial distributions of NANI and its major components were affected by land cover/use, agricultural GDP and total population. Increasing NANI has been the major cause of the degrading stream water quality over the past 20 years and is becoming a major threat to the water quality of the TGD reservoir.
Alcoholic liver disease (ALD) is a type of chronic liver disease caused by long-term heavy ethanol consumption. Danshen is one of the most commonly used substances in traditional Chinese medicine and ...has been widely used for the treatment of various diseases, and most frequently, the ALD. The current study aims to determine the potential beneficial effect of Danshen administration on ALD and to clarify the underlying molecular mechanisms. Danshen administration improved liver pathologies of ALD, attenuated alcohol-induced increment of hepatic 4-Hydroxynonenal (4-HNE) formation, and prevented hepatic Peroxisome proliferators activated receptor alpha (PPARα) suppression in response to chronic alcohol consumption. Cell culture studies revealed that both hepatoprotective effect and increased intracellular 4-HNE clearance instigated by Danshen supplementation are PPARα-dependent. In conclusion, Danshen administration can protect against ALD via inducing PPARα activation and subsequent 4-HNE degradation.
Plant parasitic nematodes (PPNs) are highly destructive and difficult to control, while conventional chemical nematicides are highly toxic and cause serious environmental pollution. Additionally, ...resistance to existing pesticides is becoming increasingly common. Biological control is the most promising method for the controlling of PPNs. Therefore, the screening of nematicidal microbial resources and the identification of natural products are of great significance and urgency for the environmentally friendly control of PPNs. In this study, the DT10 strain was isolated from wild moss samples and identified as
sp. by morphological and molecular analysis. Using
as a model, the extract of DT10 was screened for nematicidal activity, which elicited 100% lethality. The active compound was isolated from the extracts of strain DT10 using silica gel column chromatography and semipreparative high-performance liquid chromatography (HPLC). The compound was identified as spectinabilin (chemical formula C
H
O
N) using liquid chromatography mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR). Spectinabilin exhibited a good nematicidal activity on
L1 worms, with a half-maximal inhibitory concentration (IC
) of 2.948 μg/mL at 24 h. The locomotive ability of
L4 worms was significantly reduced when treated with 40 μg/mL spectinabilin. Further analysis of spectinabilin against known nematicidal drug target genes in
showed that it acts via target(s) different from those of some currently used nematicidal drugs such as avermectin and phosphine thiazole. This is the first report on the nematicidal activity of spectinabilin on
and the southern root-knot nematode
. These findings may pave the way for further research and application of spectinabilin as a potential biological nematicide.
Newcastle disease virus (NDV) is a highly infectious viral disease, which can affect chickens and many other kinds of birds. The main virulence factor of NDV, the fusion (F) protein, is located on ...the viral envelope and plays a major role in the virus' ability to penetrate cells and cause host cell fusion during infection. Multiple highly conserved tyrosine and di-leucine (LL) motifs in the cytoplasmic tail (CT) of the virus may contribute to F protein functionality in the viral life cycle.
To examine the contribution of the LL motif in the biosynthesis, transport, and function of the F protein, we constructed and rescued a NDV mutant strain, rSG10*-F/L537A, with an L537A mutation using a reverse genetic system. Subsequently, we compared the differences in the syncytium formation ability, pathogenicity, and replication levels of wild-type rSG10* and the mutated strain.
Compared with rSG10*, rSG10*-F/L537A had attenuated syncytial formation and pathogenicity, caused by a viral budding defect. Further studies showed that the LL-motif mutation did not affect the replication, transcription, or translation of the virus genome but affected the expression of the F protein at the cell surface.
We concluded that the LL motif in the NDV F CT affected the regulation of F protein expression at the cell surface, thus modulating the viral fusion ability and pathogenic phenotype.
The operating bandwidth of energy harvesters is one main concern in vibration energy harvesting due to the random and time-varying nature of most vibration sources. Recent research efforts have been ...made to address this issue including exploiting multimodal structures and nonlinear dynamics. These ideas have yielded some exciting results to leverage the broadband performance. Hybrid configurations combining these ideas are expected to provide an even better operating bandwidth and yet to be studied. In this paper, a bistable two-degree-of-freedom (2-DOF) piezoelectric energy harvester (PEH) with magnetic coupling is proposed, in which a linear parasitic oscillator attached to the main energy harvesting beam is used to generate two resonant peaks and the magnetic coupling is used to generate nonlinear dynamics, thus to achieve broadband electrical outputs. A nonlinear electromechanical model of the proposed harvester is established and the parametric study is conducted for various parasitic oscillator configurations. Experiment is subsequently performed to validate the theoretical analysis. The results indicate that nonlinear responses can appear at any of the two peaks or at both. One strong nonlinear peak in addition to a quasi-linear peak can be achieved by adequate adjustment of the parasitic oscillator. This is advantageous over the optimal linear 2-DOF PEH in terms of wider bandwidth thanks to the involved nonlinear dynamics. In addition, the load resistance has significant influence around the peak with strong nonlinear responses, resulting in evident peak shift. The best power output is accompanied with a shrunk bandwidth due to the peak shift.
•A bistable 2-DOF energy harvester with magnetic coupling is proposed, hybridizing multimodal method and nonlinear dynamics.•The linear parasitic oscillator attached aims for two resonant peaks and the magnetic coupling engages nonlinear dynamics.•The evolvement of nonlinear responses with the adjustment of the parasitic oscillator is shown.•One strong nonlinear peak in addition to a quasi-linear peak is achieved by adequately adjusting the parasitic oscillator.•The load resistance has significant influence around the peak with strong nonlinear responses in terms of peak shift.
Sugarcane yellow leaf virus (SCYLV), the causal agent of yellow leaf disease, naturally infects at least three plant species in Florida: sugarcane (Saccharum spp.), the weed Columbus grass (Sorghum ...almum) and cultivated sorghum (S. bicolor). All three hosts are also colonized by the sugarcane aphid (Melanaphis sacchari), the main vector of SCYLV worldwide. To understand the high incidence of SCYLV observed in sugarcane commercial fields and in germplasm collections, we investigated the transmission efficiency of SCYLV from sugarcane and Columbus grass to sugarcane using the sugarcane aphid and a spider mite (Oligonychus grypus) that also tested positive for SCYLV in Florida. Healthy and SCYLV-infected leaf pieces of sugarcane and Columbus grass carrying viruliferous aphids or spider mites were transferred to virus-free plants of the yellow leaf susceptible sugarcane cultivar CP96-1252. Three- and 6-months post inoculation, the 108 aphid-inoculated plants of Columbus grass and the 90 mite-inoculated plants of sugarcane tested negative for SCYLV by tissue blot immunoassay (TBIA) or reverse transcription polymerase chain reaction (RT-PCR). Similar results were obtained for 162 aphid-inoculated plants of sugarcane, except for two plants that tested positive for SCYLV by TBIA and RT-PCR. In two field experiments planted with SCYLV-free and virus-infected sugarcane (cultivar CP96-1252), only 18-28% of healthy plants became infected during a 24- to 28-month period. SCYLV prevalence in these field experiments did not differ between aphicide treated and untreated plots. Incidence of M. sacchari haplotypes in the Everglades agricultural area also indicated that the predominant haplotype that is currently colonizing sugarcane was not a vector of SCYLV in Florida. Lack of virus transmission by the spider mite suggested that this arthropod only acquired the virus when feeding on infected plants but was unable to transmit SCYLV. The current vector of SCYLV in Florida remains to be identified.
A quantitative analysis of the precipitate effects of metal ions (Al
, Fe
, Cu
, Zn
) by bovine serum albumin (BSA) on two condensed tannins (CT) from sorghum and plum was presented in this study. ...The results showed that adding metal ions enhanced the precipitation of proteins by CT, depending on the type and concentration of the metal ions used in the reaction system. The presence of metal ions and precipitation results on the CT-protein complex showed that Al
and Fe
had a higher binding ability with CT and a weaker influence on the precipitation of the CT-protein complex than Cu
and Zn
. However, when the initial reaction solution contained excessive amounts of BSA, the extra addition of metal ions had no significant effect on the amount of BSA precipitation. Reversely, adding Cu
or Zn
into the reaction solution increased the amount of precipitated BSA when the amount of CT was excessive. In addition, the amounts of CT from plum, rather than sorghum, generated more protein precipitate in the presence of Cu
or Zn
, which may be due to the different binding modes between the metal ion and the CT-BSA complex. This study also proposed a model of the interaction between the metal ion and the CT-protein precipitate.
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