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Baseflow is a vital water source for environmental and economic growth. To reveal the changes in baseflow in an arid area, Loss Plateau, China, we analyzed the annual, seasonal, and monthly baseflow fluctuations in 1981–1990 and 2006–2010. We discussed the effects of PET (potential evapotranspiration), precipitation, HI (humidity index), and temperature might have on baseflow in the basin. Results showed that the annual baseflow decreased significantly, and seasonal baseflow and baseflow index (BFI) were distributed differently in the four seasons. Baseflow and BFI were stable during the winter, but during May and June, baseflow was unstable while BFI remained stable. During 1981–1990, January and December exhibited a slight variation in baseflow, while January, May, and June exhibited a slight variation in BFI. From 2006 to 2015, baseflow was stable, with limited fluctuations in January, February, March, April, May, November, and December. The correlations between baseflow and PET, precipitation, HI, and temperature were neither statistically significant nor robust. Increases in PET, precipitation, HI, and temperature did not result in a corresponding increase or decrease in baseflow from the annual, seasonal, and monthly time scales. HIGHLIGHTS Annual, seasonal, and monthly time scale baseflow and BFI in a semi-arid river basin were analyzed.; Baseflow and BFI showed the opposite trend. A small BFI accompanied a large baseflow, and when the baseflow fluctuated, the BFI remained stable.; The correlations between baseflow (BFI) and PET, precipitation, HI, and temperature were neither statistically significant nor robust.;

Pecan (Carya illinoensis), an economically important deciduous tree, bears commercially valuable nutritional nuts. Spring freezes in April can severely injure pecan buds, decreasing bloom, and fruit set. This study determined how low temperatures affect pecan buds/flowers at different growth stages in several pecan scion/rootstock combinations. This study focused on three pecan scion/rootstock combinations: Pawnee/Peruque (PP), Kanza/Giles (KG), and Maramec/Colby (MC), grown at the Cimarron Valley Research Station, Perkins, Oklahoma. Branches at three different growth stages, i.e., outer bud scale shed, one week after bud break, and early bloom stages were collected from PP, MC, and KG. Branches were held in a Conviron E8 freezing unit at 4 temperatures (-2, 0, 2, and 4°C) for 4 and 8 hours; A total of 8 treatments. One sample set was kept as an untreated control. After 2–3 weeks, branch samples from all the temperature treatments were observed and categorized into two groups. Group one with number of branches had healthy buds/formation of healthy leaves/flowers and group two with number of dead branches. The carbohydrate content reserved from dormant was analyzed using an Anthrone reagent. Visual observations and carbohydrate analyses revealed differences in damage and carbohydrate content among the scion/rootstock combinations, low-temperature treatments, and growth stages. The MC combination had minimum visual damage to leaves, buds, and flowers and significantly lower soluble sugars and starch in bark phloem as well as significantly lower soluble sugars in woody tissue xylem. The KG combination had maximum visual damage and significantly higher soluble sugars and starches in the bark, and soluble sugars in the woody tissues. These results indicate the MC combination is more tolerant to spring freeze damage at all three growth stages compared to the other two pecan scion/rootstock combinations. The results also demonstrate the MC combination is using more non-structural carbohydrates, soluble sugars and starches, suggesting this is a possible mechanism in its freeze tolerance.

Abstract Bitcoin is a decentralized P2P cryptocurrency. It supports users to use pseudonyms instead of network addresses to send and receive transactions at the data layer, hiding users’ real network identities. Traditional transaction tracing attack cuts through the network layer to directly associate each transaction with the network address that issued it, thus revealing the sender’s network identity. But this attack can be mitigated by Bitcoin’s network layer privacy protections. Since Bitcoin protects the unlinkability of Bitcoin addresses and there may be a many-to-one relationship between addresses and nodes, transactions sent from the same node via different addresses are seen as coming from different nodes because attackers can only use addresses as node identifiers. In this paper, we proposed the evicting and filling attack to expose the correlations between addresses and cluster transactions sent from different addresses of the same node. The attack exploited the unisolation of Bitcoin’s incoming connection processing mechanism. In particular, an attacker can utilize the shared connection pool and deterministic connection eviction strategy to infer the correlation between incoming and evicting connections, as well as the correlation between releasing and filling connections. Based on inferred results, different addresses of the same node with these connections can be linked together, whether they are of the same or different network types. We designed a multi-step attack procedure, and set reasonable attack parameters through analyzing the factors that affect the attack efficiency and accuracy. We mounted this attack on both our self-run nodes and multi-address nodes in real Bitcoin network, achieving an average accuracy of 96.9% and 82%, respectively. Furthermore, we found that the attack is also applicable to Zcash, Litecoin, Dogecoin, Bitcoin Cash, and Dash. We analyzed the cost of network-wide attacks, the application scenario, and proposed countermeasures of this attack.

Global warming has increased the probability of extreme climate events, with compound extreme events having more severe impacts on socioeconomics and the environment than individual extremes. Utilizing the Coupled Model Intercomparison Project Phase 6 (CMIP6), we predicted the spatiotemporal variations of compound extreme precipitation-high temperature events in China under three Shared Socioeconomic Pathways (SSPs) across two future periods, and analyzed the changes in exposed populations and identified influencing factors. From the result, we can see that, the CMIP6 effectively reproduces precipitation patterns but exhibits biases. The frequency of compound event rises across SSPs, especially under high radiative forcing, with a stronger long-term upward trend. Furthermore, the economically developed areas, notably China's southeastern coast and North China Plain, will be hotspots for frequent and intense compound extreme events, while other regions will see reduced exposure. Finally, in the long-term future (2070-2100), there is a noteworthy shift in population exposure to compound events, emphasizing the increasing influence of population factors over climate factors. This highlights the growing importance of interactions between population and climate in shaping exposure patterns.

Spring freeze is among the problems threatening pecan bloom and production. Pecan tree height and structure make them difficult to protect from spring freezes. Some cultivars can compensate because the secondary buds can produce healthy flowers if the primary buds freeze. The mechanism that precipitates secondary budbreak is unknown. Our results show a correlation between successful secondary budbreak and 1-year-old shoot carbohydrate levels. ‘Kanza’ and ‘Pawnee’, with the higher secondary budburst, also had higher carbohydrate levels than ‘Maramec’. This suggests higher carbohydrate levels in the bud-bearing 1-year-old shoots promote successful secondary bud burst after spring freeze destruction of the primary buds.

Pecan [Carya illinoinensis (Wangenh.) K. Koch] is a member of the Juglandaceae family. During spring, pecan trees break their bud dormancy and produce new leaves and flowers. Carbohydrates stored in roots and shoots are thought to support the bloom and early vegetative growth during this time until new leaves start the full photosynthetic activity. Spring freeze is known for its damaging effects on pecan bud and flower growth and development. Pecan shoots with leaves and flowers from five scion–rootstock combinations were collected hours before and after a recent spring freeze (below 0 °C for 6 hours, 21 Apr 2021, Perkins, OK, USA). Morphologies of the leaf, bud, and catkin were visually observed, and the morphologies of the anther and pollen in paraffin sections were investigated by light microscopy. Soluble sugar and starch from bark and wood were analyzed using the anthrone reagent method. The Kanza–Mount showed the maximum damage to terminal leaves, buds, and catkins, whereas Maramec–Colby had the minimum damage only to leaves. Pollen grains were shrunk and reduced in number in the anthers in the protandrous Pawnee scions, whereas no pollen damage was observed in the protogynous Kanza scion. Furthermore, bark soluble sugar levels increased in all the scion–rootstock combinations after the freeze, which may indicate a physiological response to the cold stress. Overall, the extent of spring freeze damage of pecans is affected by the growth stage, types of scion and rootstock, and the scion–rootstock interactions. Furthermore, in addition to low temperature, scion–rootstock interactions also affected the starch and soluble sugar contents in wood and bark tissues.

Water yield (WY) is an significant characteristic that reflects ecosystem services. In order to realize high-quality development, it is vital to explore the spatial and temporal (ST) distribution of WY and its driving factors in the Yiluo River Basin (YLRB) to uphold ecological stability and advance long-term sustainable growth. This paper quantifies WY in the YLRB from 2010 to 2020 using the WY model in the InVEST toolkit. Exploring ST characteristics and driving factors at both the raster and sub-watershed levels, results indicate that the overall WY (average water depth) of the YLRB in 2010, 2015, and 2020 was 26.93 × 108 m3 (136.50 mm), 22.86 × 108 m3 (113.38 mm), and 26.81 × 108 m3 (137.61 mm), respectively. The spatial pattern of watershed WY remains consistent across various periods, illustrating spatial variation in the depth of low WY in the central and western regions and high WY depth in the eastern region. At the sub-watershed level, the Luo River (LR) Basin has the highest contribution (69%) to the WY of the entire basin and served as the principal WY region of the YLRB. Conversely, the Yiluo River section, formed after the confluence of the Yi River (YR) and the LR, has the lowest WY contribution (7%) in the entire watershed. Distinct variations exist in the WY capacity among various land use (LU) types. Construction land (CSL) and unused land (UL) exhibited the highest WY capacity (315.16 mm and 241.47 mm), whereas water area (WA) had the lowest (0.01 mm). WY was significantly positively correlated with slope, precipitation, actual evapotranspiration, percentage of cultivated land, and NDVI. It showed a significant negative correlation with altitude, WA, and population density. This study helps promote the research and development of watershed ecosystem services. It also provides scientific support resolving conflicts between watershed protection and economic development and promoting harmony in the YLRB.

Abstract NADPH provides the reducing power for decomposition of reactive oxygen species (ROS), making it an indispensable part during ROS defense. It remains uncertain, however, if living cells respond to the ROS challenge with an elevated intracellular NADPH level or a more complex NADPH-mediated manner. Herein, we employed a model fungus Aspergillus nidulans to probe this issue. A conditional expression of glucose-6-phosphate dehydrogenase (G6PD)-strain was constructed to manipulate intracellular NADPH levels. As expected, turning down the cellular NADPH concentration drastically lowered the ROS response of the strain; it was interesting to note that increasing NADPH levels also impaired fungal H2O2 resistance. Further analysis showed that excess NADPH promoted the assembly of the CCAAT-binding factor AnCF, which in turn suppressed NapA, a transcriptional activator of PrxA (the key NADPH-dependent ROS scavenger), leading to low antioxidant ability. In natural cell response to oxidative stress, we noticed that the intracellular NADPH level fluctuated “down then up” in the presence of H2O2. This might be the result of a co-action of the PrxA-dependent NADPH consumption and NADPH-dependent feedback of G6PD. The fluctuation of NADPH is well correlated to the formation of AnCF assembly and expression of NapA, thus modulating the ROS defense. Our research elucidated how A. nidulans precisely controls NADPH levels for ROS defense. Graphical Abstract

With the widespread use of smartphones, many people spend much time on smartphones for shopping, learning, socializing, and so on, which can affect an individual's mental health and work performance. Especially, individual perceived conflict at work may increase their social anxiety and thus raise the risk of their smartphone addiction. This study collected data from 577 corporate employees in China through convenience sampling to explain the influence mechanism of work conflict on smartphone addiction and to verify the moderating role of rumination. Statistical results show that relationship conflicts, task conflicts, and process conflicts positively affect smartphone addiction by enhancing social anxiety. Moreover, rumination positively moderates the relationship between work conflict and smartphone addiction. People with high rumination are more likely to escape reality due to conflict at work, which further enhances their smartphone addiction behaviors. Our study suggests that a relatively harmonious working atmosphere should be established within organizations, especially for employees with rumination. Work conflict is a predisposing factor for social anxiety and smartphone addiction in individuals with high rumination.

Abstract Following the rise of bilingual international schools in China, many learners of primary school age face huge barriers to academic success at school due to weaknesses in language proficiency. In my experience, without sufficient language support, not only is the academic growth of many young learners impeded, their social life and even their mental health suffer. This study investigates how an understanding of course design for primary learners will help prepare English language courses that support an effective transition to a bilingual school environment. Cognitive factors, physical factors, and the environment are discussed and serve as lenses through which methodologies, including needs analysis, syllabus framework, and assessments are reviewed and conducted. The overall design is considered to have reached the original goals and have fulfilled learners’ needs with evidential assessments and stakeholders’ consensus.

In classical severity–duration–frequency (SDF) analysis, the dependence between drought characteristics is not effectively considered. The present study aims to propose the SDF relationships of streamflow drought in the source area of the Yellow River (SAYR) using a copula-based approach. Comparison of multiple time-varying threshold levels and the integration and elimination of drought events were considered. Selection of marginal probability distribution and copula-based joint probability distribution was properly conducted with multiple means. Copula-based joint and conditional probabilities were computed. The findings support carrying out integration and elimination processing on the preliminarily identified streamflow droughts through a run analysis with a time-varying threshold level of the 80% quantile of daily streamflow. The Gaussian copula was selected as the optimal model for constructing bivariate joint probability distribution, with generalized extreme value and log-normal as the suitable marginal probability distributions of streamflow drought duration and severity. The proposed copula-based SDF relationships of streamflow drought events can provide more critical information in addition to univariate frequency analysis, benefitting from the joint and conditional probabilities. The multivariate probabilistic analyses can effectively consider the connection and interaction between drought characteristics, while conditional probability distribution allows analyzing the impact of one drought characteristic on another. The results also indicate a relatively high risk of streamflow drought with short duration and low severity in the region, requiring effective drought-mitigation strategies and measures.

Abstract Sulforaphane (SFN), an active compound in cruciferous vegetables, has been characterized by its antiproliferative capacity. We investigated the role and molecular mechanism through which SFN regulates proliferation and self-renewal of lung cancer stem cells. CD133+ cells were isolated with MACs from lung cancer A549 and H460 cells. In this study, we found that SFN inhibited the proliferation of lung cancer cells and self-renewal of lung cancer stem cells simultaneously. Meanwhile, the mRNA and protein expressions of Shh, Smo, Gli1 and PHC3 were highly activated in CD133+ lung cancer cells. Compared with siRNA-control group, Knock-down of Shh inhibited proliferation of CD133+ lung cancer cells, and decreased the protein expression of PHC3 in CD133+ lung cancer cells. Knock-down of PHC3 also affected the proliferation and decreased the Shh expression level in CD133+ lung cancer cells. In addition, SFN inhibited the activities of Shh, Smo, Gli1 and PHC3 in CD133+ lung cancer cells. Furthermore, the inhibitory effect of SFN on the proliferation of siRNA-Shh and siRNA-PHC3 cells was weaker than that on the proliferation of siRNA-control cells. Sonic Hedgehog signaling pathway might undergo a cross-talk with PHC3 in self-renewal of lung cancer stem cells. SFN might be an effective new drug which could inhibit self-renewal of lung cancer stem cells through the modulation of Sonic Hedgehog signaling pathways and PHC3. This study could provide a novel way to improve therapeutic efficacy for lung cancer stem cells.

Abstract Background There has been a great interest in developing strategies for enhancing antigen delivery to the mucosal immune system as well as identifying mucosal active immunostimulating agents. To elevate the potential of O-2ʹ-Hydroxypropyl trimethyl ammonium chloride chitosan (O-2ʹ-HACC) as an adjuvant and mucosal immune delivery carrier for DNA vaccine, we prepared the O-2ʹ-HACC loaded with Newcastle disease virus (NDV) F gene plasmid DNA and C3d6 molecular adjuvant (O-2ʹ-HACC/pFDNA microparticles). Results The O-2ʹ-HACC/pFDNA exhibited a regular spherical morphology with a particle size of 202.3 ± 0.52 nm, a zeta potential of 50.8 ± 8.21 mV, encapsulation efficiency of 90.74 ± 1.10%, and a loading capacity of 49.84 ± 1.20%. The plasmid DNA could be sustainably released from the O-2ʹ-HACC/pFDNA after an initial burst release. Intranasal vaccination of chickens immunized with O-2ʹ-HACC/pFDNA not only induced higher anti-NDV IgG and sIgA antibody titers but also significantly promoted lymphocyte proliferation and produced higher levels of IL-2, IL-4, IFN-γ, CD4+, and CD8 + T lymphocytes compared with the NDV commercial live attenuated vaccine. Intranasal delivery of the O-2ʹ-HACC/pFDNA enhanced humoral, cellular, and mucosal immune responses and protected chickens from the infection of highly virulent NDV compared with the intramuscular delivery. Conclusions Collectively, our findings indicated that the O-2ʹ-HACC could be used as a vaccine adjuvant and delivery system for mucosal immunity and have an immense application promise. Graphic Abstract

It is not deep enough that the theoretical and empirical analysis of economic drivers on the urban heat island (UHI) effect have been researched. Consequently, the study of economic drivers of the UHI effect is not only conducive to the governance of the UHI problem but also conducive to deepening the study of related issues in the economic field. The Yangtze River Delta (YRD) region of China has developed economic status and the special geography of estuaries and coasts. Therefore, 26 central cities in the YRD region are selected as research samples, and the period from 2003 to 2017 is taken as the observation period. The Spatio-temporal variability of UHI intensity caused by industrialization and urbanization is analyzed by using MODIS land surface temperature (LST) data and related yearbook data. The conclusions are as follows:(1) The UHI intensity of cities in the YRD region is significant and fluctuates to a certain extent. (2) Empirical analysis shows that the agglomeration of single economic factors in the process of industrialization and urbanization does correlate with the UHI intensity in the YRD region, but the correlation may show a downward trend due to the influence of exogenous factors suc0h as physical geography. (3) In terms of economic drivers, the combination of multiple factors can produce a greater UHI intensity. The model of their impacts on UHI intensity is increasingly-changed, which is from a model of Fixed Asset Investment and the Motor Vehicle Population as dominant factors to a model of multiple overlapping economic factors, and the latter has a greater impact.

Supercritical boilers have become a major development trend in coal-fired power plants, and the air distribution strategy is a key factor in the design and operation of making it fully combustible. In this paper, the mathematical and physical models of a 350 MW supercritical boiler is established, and the optimal air distribution mode of the boiler at different load is determined based on the furnace outlet temperature, NOx concentration, and O2 content. The air distribution control strategies were derived and the corresponding procedures were established. 160 MW and 280 MW were selected for positive pagoda and 180 MW and 230 MW for waist reduced. At 290–350 MW load, the effect of adjusting the combustion damper opening on the outlet oxygen is weak, so preferentially adjusting the SOFA damper opening can achieve better results. The results show good thermal efficiency and emission performance and are applicable to adjust the air distribution mode to achieve fuller combustion of supercritical boilers.

Metal-organic framework (MOF) membranes have shown unprecedented opportunities for energy efficient separation of diverse industrially important gas pairs (e.g. H2/CO2, CO2/N2, CO2/CH4, and C3H6/C3H8). Among the various factors, microstructure manipulation (including thickness, orientation, and grain boundary structure) and framework tuning (including pore size, framework rigidity/flexibility, and stimuli responsiveness) of MOF membranes have been found playing dominant roles in their separation performances. In this perspective, we highlighted some recent progress in polycrystalline MOF membranes with emphasis on the elucidation of the structure-performance relationship at different scales.

Understanding the interactions of climate-vegetation and human-vegetation has been a critical issue and increasingly attracting attention from scientific community in the field of global change research. This study investigated the heterogeneous impacts of climate change and anthropogenic activities on vegetation change by applying the trend analysis and Geodetector approach. The spatial and temporal patterns of MODIS NDVI and LAI during 2003–2017 were firstly examined in China. We then quantified the contribution and interactions effects of climatic factors (temperature and precipitation) and anthropogenic factors (population, gross domestic product and other four categories of forestry investment) on vegetation change in five typical areas of China. Both NDVI and LAI across China demonstrated a significant increasing trend over the past two decades. However, the eastern developmental regions such as Beijing-Tianjin-Hebei Region and Yangtze River Delta exhibited a decreasing trend due to fast urbanization. Socio-economical inputs (the explanatory power of forestry investment > 40%, the range of explanatory power is 0 to 100%) were identified as the dominant driving forces of vegetation change for the most of study areas. Precipitation was the most important natural influencing factor of vegetation change. We also found that the interactions between forestry investment and other factors presented much greater explanatory power on vegetation change than a single factor. Our research highlights that the afforestation program in China during the past several decades plays an important role in contributing to vegetation greening across the country. Greening and degradation, however, are largely related to landscape context, which could be due to natural change and anthropogenic impact. To maintain high levels of forests, conserving the vegetation is more important than increasing the economic development.

Landscape degradation and fragmentation has taken place across the coastal area of China over the past decades due to complex interactions between natural and anthropogenic processes, which results in various negative environmental and ecological consequences. Therefore, understanding of the spatio-temporal dynamics and underlying determinants for landscape change is increasingly recognized as essential for land use planning and policy decision making towards socio-economic sustainable development. In this study, we aimed to examine the changing trends of annual landscape patterns along the Chinese coastal zones from 1992 to 2018. By means of quantile regression and grid-by-grid random forest regression, we then quantified the heterogeneous effects of responsible climate change and human activities on landscape patterns at the grid level. The results indicated that coastal areas across China in the whole landscape level has rapidly tended towards more fragmentated, declining aggregational, complex and irregular edge shaped landscape over the past 30 years. However, opposite evolution directions of landscape patterns were observed between urban fringe (less fragmentation and more aggregation) and remote areas far away from urban center (more fragmentation and less aggregation). High changing rate of landscape metrics generally occurred in areas adjacent to the center of major urban agglomeration. Averagely, more than 40% of significant fragmented landscape mainly caused by the growth of built-up lands. The contribution rate of urbanization also varied with changes in spatial positions and different quantiles. This study employed spatially explicit methodologies to explore the dynamic of coastal landscape and associated drivers, which filled the knowledge gaps related to landscape sustainability and coastal environmental planning and management from the perspective of time and space.

Environments such as light condition influence the spread of infectious diseases by affecting insect vector behavior. However, whether and how light affects the host defense which further affects insect preference and performance, remains unclear, nor has been demonstrated how pathogens co-adapt light condition to facilitate vector transmission. We previously showed that begomoviral βC1 inhibits MYC2-mediated jasmonate signaling to establish plant-dependent mutualism with its insect vector. Here we show red-light as an environmental catalyzer to promote mutualism of whitefly-begomovirus by stabilizing βC1, which interacts with PHYTOCHROME-INTERACTING FACTORS (PIFs) transcription factors. PIFs positively control plant defenses against whitefly by directly binding to the promoter of terpene synthase genes and promoting their transcription. Moreover, PIFs interact with MYC2 to integrate light and jasmonate signaling and regulate the transcription of terpene synthase genes. However, begomovirus encoded βC1 inhibits PIFs' and MYC2' transcriptional activity via disturbing their dimerization, thereby impairing plant defenses against whitefly-transmitted begomoviruses. Our results thus describe how a viral pathogen hijacks host external and internal signaling to enhance the mutualistic relationship with its insect vector.

Windows, as key components of building facades, have received increasing attention in facade parsing. Convolutional neural networks have shown promising results in window extraction. Most existing methods segment a facade into semantic categories and subsequently employ regularization based on the structure of manmade architectures. These methods merely concern the optimization of individual windows, without considering the spatial areas or relationships of windows. This paper presents a novel windows instance segmentation method based on Mask R-CNN architecture. The method features a spatial attention region proposal network and a relation module-enhanced head network. First, an attention module is introduced in the region proposal network to generate a spatial attention map, then the attention map is multiplied with the objectness scores of the classification branch. Second, for the head network, relation modules are added to model the spatial relationships between proposals. Appearance and geometric features are combined for instance recognition. Furthermore, we constructed a new window instance segmentation dataset with 1200 annotated images. With our dataset, the average precisions of our method on detection and segmentation increased from 53.1% and 53.7% to 56.4% and 56.7% compared with Mask R-CNN. A comparison with state-of-the-art methods also proves the predominance of our proposed method.

In this paper, the physical properties of a soluble non-starch polysaccharide (EGSP) from the endosperm of Gleditsia japonica var. delavayi seeds, and its effects on starch digestibility, glucose diffusion and glycemic index (GI) were investigated. EGSP has good acid-base and thermal stability and can form high viscosity solutions at low concentrations. Its real density (RD), solubility and lowest-gelled-concentration (LGC) are 1.33 ± 0.03 g/mL, 1.24 ± 0.15 g/100 mL and 20 g/L. Besides, EGSP also had certain oil and glucose adsorption properties. In vitro experiments showed that EGSP could effectively reduce the starch digestibility and glucose diffusion rate, which might be due to its high viscosity and the abilities of hindering starch gelation. Further in vivo experiments confirmed that EGSP can reduce the GI of starchy foods and inhibit the surge of postprandial blood glucose level.

Pandemics of vector-borne human and plant diseases often depend on the behaviors of their arthropod vectors. Arboviruses, including many bunyaviruses, manipulate vector behavior to accelerate their own transmission to vertebrates, birds, insects, and plants. However, the molecular mechanism underlying this manipulation remains elusive. Here, we report that the non-structural protein NSs of Tomato spotted wilt orthotospovirus, a prototype of the Tospoviridae family and the Orthotospovirus genus, is a key viral factor that indirectly modifies vector preference and increases vector performance. NSs suppresses the biosynthesis of plant volatile monoterpenes, which serve as repellents of the vector western flower thrips (WFT, Frankliniella occidentalis). NSs directly interacts with MYC2, the jasmonate (JA) signaling master regulator and its two close homologs MYC3 and MYC4, to disable JA-mediated activation of terpene synthase genes. The dysfunction of the MYCs subsequently attenuates host defenses, increases the attraction of thrips, and improves thrips fitness. Moreover, MYC2 associated with NSs of Tomato zonate spot orthotospovirus, another Euro/Asian-type orthotospovirus, suggesting that MYC2 is an evolutionarily conserved target of Orthotospovirus species for suppression of terpene-based resistance to promote vector performance. These findings elucidate the molecular mechanism through which an orthotospovirus indirectly manipulates vector behaviors and therefore facilitates pathogen transmission. Our results provide insights into the molecular mechanisms by which Orthotospovirus NSs counteracts plant immunity for pathogen transmission.

This study investigated the responses of winter wheat to drought for the above part of the Bengbu Sluice in the Huaihe River based on the daily scale dataset of 60 meteorological stations from 1961–2015. Crop water deficit index (CWDI) and relative moisture index (M) were used to examine the winter wheat drought and meteorological drought, respectively. We then analyzed the spatial-temporal evolution characteristics of these two kinds of drought to calculate the time lag of winter wheat drought to meteorological drought, and finally discuss the relationship between the time lag of winter wheat drought to meteorological drought and the underlying surface geographical factors, and drew the following conclusions. (1) In terms of time scale, for CWDI, except for the filling and mature period, the CWDI at other growth periods showed a slight downward trend; for M, there was no significant change in the interannual trend of each growth period. In terms of spatial scale, the proportion of above moderate drought level in each station of CWDI and M presented a decreasing feature from north to south. (2) The time lag of winter wheat drought to meteorological drought was the shortest (3.21 days) in the greening and heading period and the longest in the over-wintering period (84.35 days). (3) The correlation between the geographical factors and the time lag of winter wheat drought in each growth period was better than 0.5. The high-value points of the relation between the underlying surface geographical factors and the time lag of winter wheat drought were mostly distributed in the mountainous areas with poor soil field capacity and at a greater depth of shallow groundwater, high elevation and steep slope in the areas with aspects to the east and northeast, and the northern areas with less precipitation and lower temperature.

Vegetable oil is an important renewable resource for dietary consumption for human and livestock, and more recently for biodiesel production. Lipid traits in crops are controlled by multiple quantitative trait loci (QTLs) and each of them has a small effect on lipid traits. So far, there is limited success to increase lipid yield and improve lipid quality in plants. Here, we reported the identification of a homolog of APETALA2 (AP2) transcription factor WRINKLED1 (JcWRI1) from an oleaginous plant Jatropha curcas and characterized its function in Jatropha and Arabidopsis thaliana. Using physical mapping data, we located JcWRI1 in a QTL region specifying high oleate and lipid content in Jatropha. Overexpression of JcWRI1 in Jatropha elevated seed lipid content and increased seed mass. Lipid profile in seeds of over-expression plants showed higher oleate content which will be beneficial to improve biodiesel quality. Overexpression of JcWRI1 activated lipid-related gene expression and JcWRI1 was shown to directly bind to the AW-box of promoters of some of these genes. In conclusion, we were able to increase seed lipid content and improve seed lipid quality in Jatropha by manipulating one key transcription factor JcWRI1.

It is widely acknowledged that urban form significantly affects urban thermal environment, which is a key element to adapt and mitigate extreme high temperature weather in high-density urban areas. However, few studies have discussed the impact of physical urban form features on the land surface temperature (LST) from a perspective of comprehensive urban spatial structures. This study used the ordinary least-squares regression (OLS) and random forest regression (RF) to distinguish the relative contributions of urban form metrics on LST at three observation scales. Results of this study indicate that more than 90% of the LST variations were explained by selected urban form metrics using RF. Effects of the magnitude and direction of urban form metrics on LST varied with the changes of seasons and observation scales. Overall, building morphology and urban ecological infrastructure had dominant effects on LST variations in high-density urban centers. Urban green space and water bodies demonstrated stronger cooling effects, especially in summer. Building density (BD) exhibited significant positive effects on LST, whereas the floor area ratio (FAR) showed a negative influence on LST. The results can be applied to investigate and implement urban thermal environment mitigation planning for city managers and planners.

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Aberrant viral RNAs produced in infected plant cells serve as templates for the synthesis of dsRNAs. The derived virus-related small interfering RNAs (siRNA) mediate cleavage of viral RNAs by post-transcriptional gene silencing (PTGS), thus blocking virus multiplication. Here, we identified ASYMMETRIC LEAVES2 (AS2) as a new component of plant P body complex which mediates mRNA decapping and degradation. We found that AS2 promotes DCP2 decapping activity, accelerates mRNA turnover rate, inhibits siRNA accumulation and functions as an endogenous suppressor of PTGS. Consistent with these findings, as2 mutant plants are resistant to virus infection whereas AS2 over-expression plants are hypersensitive. The geminivirus nuclear shuttle protein BV1 protein, which shuttles between nuclei and cytoplasm, induces AS2 expression, causes nuclear exit of AS2 to activate DCP2 decapping activity and renders infected plants more sensitive to viruses. These principles of gene induction and shuttling of induced proteins to promote mRNA decapping in the cytosol may be used by viral pathogens to weaken antiviral defenses in host plants.

Using three different assays, we examined 103 serum samples collected from different civet farms and a market in China in June 2003 and January 2004. While civets on farms were largely free from SARS-CoV infection, ≈80% of the animals from one animal market in Guangzhou contained significant levels of antibody to SARS-CoV, which suggests no widespread infection among civets resident on farms, and the infection of civets in the market might be associated with trading activities under the conditions of overcrowding and mixing of various animal species.

Small molecules that can specifically bind to a DNA abasic site (AP site) have received much attention due to their importance in DNA lesion identification, drug discovery, and sensor design. Herein, the AP site binding behavior of sanguinarine (SG), a natural alkaloid, was investigated. In aqueous solution, SG has a short-wavelength alkanolamine emission band and a long-wavelength iminium emission band. At pH 8.3, SG experiences a fluorescence quenching for both bands upon binding to fully matched DNAs without the AP site, while the presence of the AP site induces a strong SG binding and the observed fluorescence enhancement for the iminium band are highly dependent on the nucleobases flanking the AP site, while the alkanolamine band is always quenched. The bases opposite the AP site also exert some modifications on the SG's emission behavior. It was found that the observed quenching for DNAs with Gs and Cs flanking the AP site is most likely caused by electron transfer between the AP site-bound excited-state SG and the nearby Gs. However, the flanking As and Ts that are not easily oxidized favor the enhanced emission. This AP site-selective enhancement of SG fluorescence accompanies a band conversion in the dominate emission from the alkanolamine to iminium band thus with a large emission shift of about 170 nm. Absorption spectra, steady-state and transient-state fluorescence, DNA melting, and electrolyte experiments confirm that the AP site binding of SG occurs and the stacking interaction with the nearby base pairs is likely to prevent the converted SG iminium form from contacting with water that is thus emissive when the AP site neighbors are bases other than guanines. We expect that this fluorophore would be developed as a promising AP site binder having a large emission shift.

Pecan (Carya illinoensis), an economically important deciduous tree, bears commercially valuable nutritional nuts. Spring freezes in April can severely injure pecan buds, decreasing bloom, and fruit set. This study determined how low temperatures affect pecan buds/flowers at different growth stages in several pecan scion/rootstock combinations. This study focused on three pecan scion/rootstock combinations: Pawnee/Peruque (PP), Kanza/Giles (KG), and Maramec/Colby (MC), grown at the Cimarron Valley Research Station, Perkins, Oklahoma. Branches at three different growth stages, i.e., outer bud scale shed, one week after bud break, and early bloom stages were collected from PP, MC, and KG. Branches were held in a Conviron E8 freezing unit at 4 temperatures (-2, 0, 2, and 4°C) for 4 and 8 hours; A total of 8 treatments. One sample set was kept as an untreated control. After 2-3 weeks, branch samples from all the temperature treatments were observed and categorized into two groups. Group one with number of branches had healthy buds/formation of healthy leaves/flowers and group two with number of dead branches. The carbohydrate content reserved fromdormant was analyzed using an Anthrone reagent. Visual observations and carbohydrate analyses revealed differences in damage and carbohydrate content among the scion/rootstock combinations, low-temperature treatments, and growth stages. The MC combination had minimum visual damage to leaves, buds, and flowers and significantly lower soluble sugars and starch in bark phloem as well as significantly lower soluble sugars in woody tissue xylem. The KG combination had maximum visual damage and significantly higher soluble sugars and starches in the bark, and soluble sugars in the woody tissues. These results indicate the MC combination is more tolerant to spring freeze damage at all three growth stages compared to the other two pecan scion/rootstock combinations. The results also demonstrate the MC combination is using more non-structural carbohydrates, soluble sugars and starches, suggesting this is a possible mechanism in its freeze tolerance. [ABSTRACT FROM AUTHOR]