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1.
PLoS One ; 18(10): e0292286, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37856484

RESUMEN

Public procurement is an important bridge between public demand and market supply and may affect corporate behavior. However, in the advocacy of sustainable development, the extant research has rarely combined sustainable public procurement (SPP) with corporate ESG performance, to explore whether governments have contributed to the development of sustainable corporate performance through their sustainable procurement activities. This paper fills in the gap by matching the actual implementation of SPP of 42,369 projects in China over 2015~2020 with 20,125 corporate ESG performance data, to analyze the relationship between SPP implementation and corporate ESG performance. The results show that the implementation of SPP has a significant positive impact on corporate ESG performance. Further heterogeneity analysis reveals that the impact is stronger in China's eastern and central regions than in other regions, and corporates at a mature stage are more likely to follow the government sustainable behavior. In addition, the implementation of SPP has a long-term effect on corporate ESG performance. The above findings have important policy implications: firstly, there is a better role for government to play as the "invisible hand", to participate in the market economy; Specifically, SPP policy should be added to government policy tool box to improve corporate ESG performance in addition to disclosure requirement, and the SPP policy employed should in particular attend to the "missing sectors" of sustainability in SPP for the good of corporate ESG; secondly, the government should implement differentiated policies tailored to the region's economic development conditions and corporate development characteristics; thirdly, a long-term evaluation mechanism should be established so that the government can play a more long-term demonstration and leading role.


Asunto(s)
Organizaciones , Corporaciones Profesionales , Desarrollo Sostenible , China , Gobierno , Organizaciones/economía , Organizaciones/organización & administración , Política Pública , Corporaciones Profesionales/economía , Corporaciones Profesionales/organización & administración , Comercio/economía , Comercio/organización & administración , Desarrollo Sostenible/economía
2.
PLoS One ; 18(3): e0282542, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36893186

RESUMEN

Performance-based evaluation criteria (PBEC) are vital for selecting high-quality suppliers and achieving a PPP procurement performance. Through theoretical and institutional analysis, we found that the selection of PBEC centered on operations depends on the discretion of the purchaser. However, in an emerging and transforming PPP market, many factors have affected the scientific exercise of the purchaser's discretion. This means that PPP projects must focus on construction and neglect operation in a certain period. Furthermore, to explore the influencing factors of the definition of PBEC, based on data of 9082 PPP projects between 2009 and 2021 in China, we adopted Ordinary Least Squares to empirically analyze two factors that influence the level of attention that is paid to the operation plan: corruption and accountability. The results indicate that the attention paid to the operation plan significantly increased with the reduction in corruption and the improvement in accountability. Robustness tests demonstrate the robustness of the results. A further heterogeneity analysis shows that the above factors have a more significant impact on non-state demonstration projects and projects with large investments. The contributions of this study are as follows: (1) Theoretically, this paper supplements the relevant research on evaluation criteria and provides new evidence on the impact of corruption and accountability on the defining PBEC. (2) Institutionally, it provides specific paths to limit the discretion of procurement officials when defining evaluation criteria. (3) In practice, it helps procurement officials to scientifically define PBEC and promote the realization of procurement performance.


Asunto(s)
Responsabilidad Social , China
3.
New Phytol ; 236(6): 2131-2150, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36161284

RESUMEN

Drought limits apple yield and fruit quality. However, the molecular mechanism of apple in response to drought is not well known. Here, we report a Cys2/His2 (C2H2)-type zinc-finger protein, MdZAT5, that positively regulates apple drought tolerance by regulating drought-responsive RNAs and microRNAs (miRNAs). DNA affinity purification and sequencing and yeast-one hybrid analysis identified the binding motifs of MdZAT5, T/ACACT/AC/A/G. Chromatin immunoprecipitation quantitative polymerase chain reaction (ChIP-qPCR) and electrophoretic mobility shift assays (EMSAs) showed that MdZAT5 directly binds to the promoters of the drought-responsive genes including MdRHA2a, MdLEA14, MdTPX1, and MdCAT3, and activates their expression under drought stress. MdZAT5 interacts with and directly targets HYPONASTIC LEAVES1 (MdHYL1). MdZAT5 may facilitate the interaction of MdHYL1 with pri-miRNAs or MdDCL1 by activating MdHYL1 expression, thereby regulating the biogenesis of drought-responsive miRNAs. Genetic dissection showed that MdHYL1 is essential for MdZAT5-mediated drought tolerance and miRNA biogenesis. In addition, ChIP-qPCR and EMSA revealed that MdZAT5 binds directly to the promoters of some MIR genes including Mdm-miR171i and Mdm-miR172c, and modulates their transcription. Taken together, our findings improve our understanding of the molecular mechanisms of drought response in apple and provide a candidate gene for the breeding of drought-tolerant cultivars.


Asunto(s)
Malus , MicroARNs , Sequías , Malus/genética , MicroARNs/genética , Regulación de la Expresión Génica de las Plantas , ARN Mensajero , Fitomejoramiento , Estrés Fisiológico/genética
4.
Plant Cell ; 34(10): 3983-4006, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-35897144

RESUMEN

Miniature inverted-repeat transposable elements (MITEs) are widely distributed in the plant genome and can be methylated. However, whether DNA methylation of MITEs is associated with induced allelic expression and drought tolerance is unclear. Here, we identified the drought-inducible MdRFNR1 (root-type ferredoxin-NADP+ oxidoreductase) gene in apple (Malus domestica). MdRFNR1 plays a positive role in drought tolerance by regulating the redox system, including increasing NADP+ accumulation and catalase and peroxidase activities and decreasing NADPH levels. Sequence analysis identified a MITE insertion (MITE-MdRF1) in the promoter of MdRFNR1-1 but not the MdRFNR1-2 allele. MdRFNR1-1 but not MdRFNR1-2 expression was significantly induced by drought stress, which was positively associated with the MITE-MdRF1 insertion and its DNA methylation. The methylated MITE-MdRF1 is recognized by the transcriptional anti-silencing factors MdSUVH1 and MdSUVH3, which recruit the DNAJ domain-containing proteins MdDNAJ1, MdDNAJ2, and MdDNAJ5, thereby activating MdRFNR1-1 expression under drought stress. Finally, we showed that MdSUVH1 and MdDNAJ1 are positive regulators of drought tolerance. These findings illustrate the molecular roles of methylated MITE-MdRF1 (which is recognized by the MdSUVH-MdDNAJ complex) in induced MdRFNR1-1 expression as well as the drought response of apple and shed light on the molecular mechanisms of natural variation in perennial trees.


Asunto(s)
Sequías , Malus , Alelos , Catalasa/genética , Elementos Transponibles de ADN/genética , Ferredoxinas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Malus/genética , Malus/metabolismo , Metilación , NADP/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Front Public Health ; 10: 897731, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35707059

RESUMEN

Good governance is the basis of dealing with major emergencies and protecting public health. It has become a major issue of the central government to construct a scientific procurement and supply system of emergency supplies. This article constructs the analytical framework of strategic procurement and expounds the realization mechanism of strategic procurement under an emergency situation to reflect China's procurement practice in COVID-19 response and improve public health and governance. Using case study, semi-structured interviews, and the Nvivo text analysis, this study found that emphasizing the strategic function of securing the public health,the top status of MSG, cross-sector procurement team, strong procurement and supply integration, comprehensive and in-depth procurement synergy mechanism are the successful experiences of China's emergency procurement. However, due to the temporary nature of the emergency procurement mechanism, strategic procurement planning, procurement management specialization, and procurement supply integration still need to be improved. The findings of this study further suggest that to improve public health and governance, it is pivotal to reconstruct the government procurement law to make it compatible with the emergency procurement and transform the government procurement system into a strategic procurement in a consistent and coherent way.


Asunto(s)
COVID-19 , COVID-19/prevención & control , Gobierno , Humanos , Salud Pública
6.
Environ Sci Pollut Res Int ; 29(44): 66109-66124, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35501434

RESUMEN

This paper investigates volatility spillovers between the global crude oil market and the stock markets of the global oil stock markets (Russian, Canada, China, Kuwait, and the USA) pre and after the COVID-19 pandemic. We use wavelet Granger causality methods to study the volatility spillovers between global oil stock markets, mainly from January 1, 2019, to March 31, 2021. Our Results (1) shows that WTI and Brent oil prices had a negative mean return before COVID-19 but a positive mean return during the pandemic spread. Other Results (2) find the positive, significantly lowest, and highest frequency during the COVID-19 outbreak for all selected countries. The results also show that the link between oil WTI & Brent prices and stock markets return in the lowest (33-66 days) and highest frequency range (4-16) before the Covid-19 epidemic, especially in the first quarter of 2020. Before the COVID-19 period, the Russian oil stock market is seriously prejudiced with oil prices on a modest scale, but not after the pandemic's start. This study also perceives direction opposite between the COVID-19 period. The Canadian and United States America oil and stock markets influence the lowest scale in the previous COVID-19 sample for the U.S. market. Moreover, this paper exposed that oil marketing highest oil futures in their portfolios than stock shares for all times. We found that oil price shocks had a more significant impact on the stock markets of the United States and Canada than on the stock markets of other countries.


Asunto(s)
COVID-19 , Petróleo , COVID-19/epidemiología , Canadá/epidemiología , Humanos , Mercadotecnía , Pandemias , Estados Unidos
7.
Front Psychol ; 13: 832617, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35602741

RESUMEN

The selection of the procurement model, which is a process of discretion exercised by procurement officials, is crucial to the Public-private Partnership (PPP) procurement performance. From theoretical analysis and international practice, we could find that the negotiation method is more suitable for complex PPP projects, while the tendering method is widely used in China's PPP procurement. To analyze the reasons for the phenomenon, we used the logit regression model to examine the influence of regulatory competition, risk aversion preference, and tacit interaction on the procurement model selection based on the data of 8,926 PPP projects from 2009 to 2021 in China. The results indicate that regulatory competition leads to confusion in procurement model selection, while risk aversion preference and tacit interaction significantly promote the application of tendering. Moreover, the heterogeneity analysis of regions and return models prove that provincial capitals and municipalities are more susceptible to regulatory competition, risk aversion preference, and tacit interaction than ordinary cities. Compared with user-pay projects, government-pay projects and viability gap funding projects are more susceptible to regulatory competition and risk aversion preference, and less affected by tacit interaction. Therefore, to optimize the procurement model selection, policymakers should improve procurement policies to reduce the adverse effects of regulatory competition, risk aversion preference, and tacit interactions.

8.
Plant Physiol ; 188(3): 1686-1708, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-34893896

RESUMEN

Drought stress tolerance is a complex trait regulated by multiple factors. Here, we demonstrate that the miRNA160-Auxin Response Factor 17 (ARF17)-HYPONASTIC LEAVES 1 module is crucial for apple (Malus domestica) drought tolerance. Using stable transgenic plants, we found that drought tolerance was improved by higher levels of Mdm-miR160 or MdHYL1 and by decreased levels of MdARF17, whereas reductions in MdHYL1 or increases in MdARF17 led to greater drought sensitivity. Further study revealed that modulation of drought tolerance was achieved through regulation of drought-responsive miRNA levels by MdARF17 and MdHYL1; MdARF17 interacted with MdHYL1 and bound to the promoter of MdHYL1. Genetic analysis further suggested that MdHYL1 is a direct downstream target of MdARF17. Importantly, MdARF17 and MdHYL1 regulated the abundance of Mdm-miR160. In addition, the Mdm-miR160-MdARF17-MdHYL1 module regulated adventitious root development. We also found that Mdm-miR160 can move from the scion to the rootstock in apple and tomato (Solanum lycopersicum), thereby improving root development and drought tolerance of the rootstock. Our study revealed the mechanisms by which the positive feedback loop of Mdm-miR160-MdARF17-MdHYL1 influences apple drought tolerance.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Adaptación Fisiológica/genética , Sequías , Ácidos Indolacéticos/metabolismo , Malus/genética , Malus/metabolismo , MicroARNs/efectos de los fármacos , Productos Agrícolas/genética , Productos Agrícolas/metabolismo , Deshidratación/genética , Deshidratación/fisiopatología , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente
9.
Stress Biol ; 1(1): 13, 2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37676571

RESUMEN

The wax layer of apple leaves plays an important role in improving stress resistance, but relatively little is known about the mechanisms of wax synthesis and transport in apple leaves. In this study, 17 wax components, including alcohols, alkanes, fatty acids and terpenes, were analyzed by gas chromatography-tandem mass spectrometry (GC-MS) from the leaves of 123 apple germplasms. Whole-genome sequencing of these apple accessions yielded 5.9 million high-quality single nucleotide polymorphisms (SNPs). We performed a genome-wide association study (GWAS) on 17 wax components and identified several genes related to wax synthesis and transport, including MdSHN1 (SHINE1), MdLTP4 (LIPID TRANSFER PROTEIN4), MdWSD1 (WAX ESTER SYNTHASE/ACYL-COA DIAC-YLGLYCEROL ACYLTRANSFERASE1), MdRDR1 (RNA-DEPENDENT RNA POLYMERASE1), MdACBP6 (ACYL-COA-BINDING PROTEIN6), MdNLE (NOTCHLESS) and MdABCG21 (ATP-BINDING CASSETTE G21). Moreover, we identified some prominent SNPs that may affect gene expression and protein function. These results provide insights into mechanisms of wax synthesis and transport in apple leaves and broaden the genetic resources and basis for facilitating resistance breeding.

10.
J Exp Bot ; 72(2): 592-607, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-32995885

RESUMEN

The phytohormone abscisic acid (ABA) is involved in various plant processes. In response to drought stress, plants quickly accumulate ABA, but the regulatory mechanism of ABA accumulation is largely unknown, especially in woody plants. In this study, we report that MdMYB88 and MdMYB124 are myeloblastosis (MYB) transcription factors critical for ABA accumulation in apple trees (Malus x domestica) following drought, and this regulation is negatively controlled by ABA. MdMYB88 and MdMYB124 positively regulate leaf water transpiration, photosynthetic capacity, and stress endurance in apple trees under drought conditions. MdMYB88 and MdMYB124 regulate the expression of biosynthetic and catabolic genes of ABA, as well as drought- and ABA- responsive genes. MdMYB88 associates with promoter regions of the ABA biosynthetic gene 9-cis-epoxycarotenoid dioxygenase 3 (NCED3). Finally, expression of MdMYB88 and MdMYB124 is repressed by ABA. Our results identify a feedback regulation of MdMYB88 and MdMYB124 in modulating ABA homeostasis in apple trees.


Asunto(s)
Ácido Abscísico , Proteínas de Plantas , Sequías , Retroalimentación , Regulación de la Expresión Génica de las Plantas , Homeostasis , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Estrés Fisiológico
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