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Climate change caused by carbon emissions has a strong influence on the economy and human society. Though numerous previous studies have emphasized the importance of low-carbon innovation on curbing or mitigating carbon emissions, not much attention has been given to the reverse effect. We used a panel of 285 Chinese prefecture-level cities from 2005 to 2016 and Cooperative Patent Classification (CPC)-Y02 patents as low-carbon innovation indicators. The results show that the increasing carbon emissions accelerate cities' low-carbon innovation in China, and the predicted effect varies across low-carbon innovation types. As carbon emissions rise, more low-carbon innovation will occur in activities with higher carbon emissions. Besides, we explore environmental awareness as the mediation channel for carbon emissions to impact low-carbon innovation. With the help of media, government, and enterprises, the growing carbon emissions promote public environmental awareness and change consumers' behaviors, motivating companies to speed up low-carbon innovation. [ABSTRACT FROM AUTHOR]

Cucumber is an economically important horticultural crop that is highly dependent on nitrogen fertilizer. Nitrate is the main nitrogen source for cucumber; however, the effects of nitrogen signaling on the early-stage growth of cucumber seedlings and the related regulatory mechanisms are still unclear. To compare seedling growth status at different nitrate levels, we performed a growth experiment using cucumber seedlings that had nearly exhausted their nitrogen reserves under nitrogen deficiency conditions (NO3−-N/NH4+-N = 0 in MS medium). Using qPCR and in situ RNA hybridization localization of candidate CsNPF genes, we found that short-term nitrogen deficiency promoted changes in root vascular bundle morphology and xylem growth in cucumber seedlings, thereby enhancing their growth potential. Among the candidate genes, CsNPF7.2, a gene located in the vascular cambium was found to be induced by short-term nitrogen deficiency. Considering the abundance of vasculature development marker genes, we speculated that the function of CsNPF7.2 might relate to the development of vascular bundles in plants suffering from nitrogen stress. The objective of our study was to investigate the growth changes in cucumber seedlings in response to different nitrogen levels, and to examine the mRNA accumulation and expression patterns of nitrate transporter CsNPF genes, so that critical genes can be identified to improve nitrogen use efficiency in cucumber cultivation. The results of this study provides a novel theoretical basis for optimizing cultivation, regulating rational fertilization levels, and improving nitrogen use efficiency in production. In addition, our study also provides new avenues for the further study of the function of CsNPF7.2 on regulating vasculature development in response to nitrogen stress. [ABSTRACT FROM AUTHOR]

Extension and clustering of polycyclic aromatic hydrocarbons (PAHs) are key mechanistic steps for coking and deactivation in catalysis reactions. However, no unambiguous mechanistic picture exists on molecule-resolved PAHs speciation and evolution, due to the immense experimental challenges in deciphering the complex PAHs structures. Herein, we report an effective strategy through integrating a high resolution MALDI FT-ICR mass spectrometry with isotope labeling technique. With this strategy, a complete route for aromatic hydrocarbon evolution is unveiled for SAPO-34-catalyzed, industrially relevant methanol-to-olefins (MTO) as a model reaction. Notable is the elucidation of an unusual, previously unrecognized mechanistic step: cage-passing growth forming cross-linked multi-core PAHs with graphene-like structure. This mechanistic concept proves general on other cage-based molecule sieves. This preliminary work would provide a versatile means to decipher the key mechanistic step of molecular mass growth for PAHs involved in catalysis and combustion chemistry. Coke-induced catalyst deactivation draws increasing concerns in industrially catalytic processes. Here the authors provide a strategy integrating advanced mass spectroscopy and isotope labeling to uncover a cage-passing molecular route of coking species in molecular sieve catalysts. [ABSTRACT FROM AUTHOR]

Four types of SAPO-34's surface methoxy species (CH3-SAPO-34) structures have been studied by periodic density functional theory calculations. The most stable CH3-SAPO-34 structure is the methyl cation locating on the framework oxygen anion site O(z1), which is at the middle position of a cha composite building unit. [ABSTRACT FROM AUTHOR]

Climate change has an indirect effect on water quality in freshwater ecosystems, but it is difficult to assess the contribution of climate change to the complex system. This study explored to what extent climatic indicators (air temperature, wind speed, and rainfall) influence nutrients and oxygen levels in a shallow reservoir, Yuqiao Reservoir, China. The study comprises three parts—describing the temporal trends of climatic indicators and water quality parameters during the period 1992-2011, analyzing the potential impacts of climate on water quality, and finally developing a quantitative assessment to evaluate how climatic factors govern nutrient levels in the reservoir. Our analyses showed that the reservoir experienced substantial cold periods (1992-2001) followed by a warm period (2002-2011). The results showed that increasing air temperature in spring, autumn, and winter and increasing annual wind speed decrease total phosphorus (TP) concentration in the reservoir in spring, summer, and winter. According to the quantitative assessment, the increase in air temperature in spring and winter had a larger contribution to the decrease in TP concentration (47.2 and 64.1%), compared with the influence from decreased wind speed and rainfall. The field data suggest that nutrients decline due to enhanced uptake by macrophytes in years when spring was warmer and the macrophytes started to grow earlier in the season. The increasing wind speed and air temperature in spring also significantly contribute to the increase in dissolved oxygen concentration. This study helps managers to foresee how potential future climate change might influence water quality in similar lake ecosystems. [ABSTRACT FROM AUTHOR]

To explore the correlations among water quality parameters, suspended solids (SS) and total dissolved solids (TDS) with meteorological factors in a shallow reservoir in China, the long-term variations of water quality were considered. A non-parametric regression method, generalized additive models (GAM), was used to analyse the correlations among eleven physicochemical and biological parameters as well as three meteorological factors (wind speed, rainfall and solar radiation) which we collected from 2000 to 2011. The results indicate that the three meteorological factors may have positive effects on SS. Moreover, statistically significant correlations between many water quality parameters and SS or TDS were exhibited seasonally. The correlations between electrical conductivity (EC) and SS were opposite to correlations between EC and TDS. This finding reveals that TDS have a positive impact on EC, while EC negatively affects SS. The results indicated that many parameters, such as total nitrogen, total phosphorus, biological oxygen demand (BOD) and chemical oxygen demand (COD), were related to SS due to the adsorption of SS. Moreover, both positive and negative correlations between COD and TDS were observed in this freshwater reservoir. The positive correlation between chlorophyll a and SS suggested that the change of SS concentration in autumn was caused by the growth of algae . Meanwhile, significant correlations between SS and meteorological factors were also observed, indicating that meteorological factors had effects on SS dynamics. This study provides useful information regarding the correlations among water quality parameters, SS and TDS with meteorological factors in a freshwater reservoir. [ABSTRACT FROM AUTHOR]

KNOTTED1 (KN1)-like homologous box is a homeodomain transcription factor that is transported intercellularly through plasmodesmata and over long distances via phloem transport in plants. In this study, we investigated KN1 long-distance transport and its regulation by the viral movement protein binding protein of 'Du Li' ( Pyrus betulaefolia, PbMPB2C) in two species of fruit trees, 'Du Li' (rootstock) and 'Ya Li' ( P. bretschneideri, scion), using grafting experiments. The results showed that PbKN1 mRNA was present in the phloem in both transport directions across the graft junctions of tissue-cultured grafted plants and orchard saplings. To investigate the relationship between PbKN1 and PbMPB2C, we conducted interaction assays to demonstrate their physical interaction. An RNA-protein pull-down assay revealed that PbKN1 mRNA interacted with PbMPB2C protein in vitro but not with PbKN1 and that PbKN1 repressed the binding of PbMPB2C to PbKN1 mRNA. Additionally, using p35S:GFP- PbKN1 transgenic tobacco grafted with wild-type plants, we found that the movement of PbKN1 was increased by the silencing of NtMPB2C. Based on the above findings, we first demonstrate evidence of the bidirectional transport of PbKN1 mRNA and propose that PbMPB2C could act as a negative regulator of the phloem-mediated long-distance transport of PbKN1 mRNA. [ABSTRACT FROM AUTHOR]

The sieve tube in higher plants functions as infrastructure for long-distance transport of nutrients, photoassimilates, and growth regulators including hormones. Recently, it was revealed that some protein and RNA molecules also function as movable growth regulators in the sieve tube. In the case of the mRNA of gibberellic acid insensitive ( GAI), the transport evidence was obtained through identification of the overproduced transgene transcript. In this work, we investigated the transport of apple ( Malus x domestica cv. Fuji and Malus xiaojinensis) endogenous GAI mRNA by grafting experiments. Each GAI mRNA of scion and stock plants was detected in the graft partners as from 5 days after grafting, indicating that the GAI mRNA moves in both upward and downward directions via the graft union. [ABSTRACT FROM AUTHOR]

Toona sinensis is a deciduous tree native to eastern and southeastern Asia that has important culinary and cultural values. To expand current knowledge of the transcriptome and functional genomics in this species, a de novo transcriptome sequence analysis of young and mature leaf tissues of T. sinensis was performed using the Illumina platform. Over 8.1 Gb of data were generated, assembled into 64,541 unigenes, and annotated with known biological functions. Proteins involved in primary metabolite biosynthesis were identified based on similarities to known proteins, including some related to biosynthesis of carbohydrates, amino acids, lipids, and energy. Analysis of unigenes differentially expressed between young and mature leaves (transcriptomic libraries 'YL' and 'ML', respectively) showed that the KEGG pathways of phenylpropanoid, naringenin, lignin, cutin, suberin, and wax biosynthesis were significantly enriched in mature leaves. These results not only expand knowledge of transcriptome characteristics for this valuable species, but also provide a useful transcriptomic dataset to accelerate the researches on its metabolic mechanisms and functional genomics. This study can also further the understanding of unique aromatic metabolism and Chinese medicinal properties of T. sinensis. [ABSTRACT FROM AUTHOR]

To identify quantitative trait loci (QTLs), a large F2 population in foxtail millet including 543 plants from a cross between Aininghuang and Jingu 21 was used to construct a high-density linkage map based on restriction site-associated DNA sequencing (RAD-seq). Based on the map, QTLs for 11 various agronomic traits, consisting of PH, PL, PD, PNL, FID, SID, PW, GW, TGW, PT and PC, were mapped. The map contained 3129 Bin markers from 48,790 single nucleotide polymorphisms (SNPs) spanning 1460.996 cM. Fifty-seven QTLs related to these 11 agronomic traits were detected using composite interval mapping (CIM), which explained 0.38–30.52% of total phenotypic variation explained (PVE). Among those, five major QTLs with a large PVE of more than 10%, including qPH5-2 for PH, qPD5-2 for PD, qPW5-1 for PW and qPC7-1 and qPC7-2 for PC, were detected. Notably, an extremely large effect QTL with a PVE of 30.52%, the qPH5-2 for PH, was observed. Furthermore, we newly developed five markers, which could be used for marker-assisted selection. Then, we verified these QTLs including qPC7-2 for PC, qPW5-1 for PW and qPH5-2 for PH were positive via correlation analysis of markers to traits in the natural population and the advanced generation population (AJF5) derived from the mapping population by single seed descent. Additionally, we found two multi-effect Mqtls, Mqtl5-2 and Mqtl2-5, underlying panicle development and yield, and one Mqtl, Mqtl1-2, probably related to plant growth and development by QTL prioritisation via Meta-QTL analysis. Moreover, we discussed candidate genes for the five major QTLs. Thus, mapping QTLs by RAD-seq using a large F2 population is efficient, and the present study offers valuable insights into the genetic basis of quantitative traits and marker-assisted selection in foxtail millet. [ABSTRACT FROM AUTHOR]

G proteins regulate shoot, root, and epidermis development, as well as biotic stress tolerance in plants; however, most studies have examined model plants and less attention has been paid to the function of G proteins in horticultural plants. Here, we identified a G protein, CsGPA1, from cucumber and studied its function in seedling development of cucumbers. CsGPA1 is a peptide of 392 amino acids with a predicted molecular mass of 44.6 kDa. Spatiotemporal expression analysis found that endogenous CsGPA1 was highly expressed in roots and young leaves. Immunohistochemical assay revealed that functional CsGPA1 was present in the plasma membranes of the epidermis and cortex, and in the cytosol of the endodermis, parenchyma, and vasculature of root meristematic cells. In comparison with wild-type seedlings, CsGPA1-overexpressing transgenic lines exhibited enhanced seed germination and earlier seedling development including hypocotyl elongation and root growth. In contrast, RNAi silencing of the CsGPA1 gene inhibited seedling growth and development. Further study showed that CsGPA1 controled hypocotyl elongation and root growth via promoting cell size and the meristem of hypocotyl and root tip cells of cucumber plants. Our study expands the roles of G proteins in plants and helps to elucidate the mechanism by which cucumber regulates early seedling development. [ABSTRACT FROM AUTHOR]