Floral transition initiates reproductive development of plants and occurs in response to environmental and endogenous signals. In Arabidopsis thaliana, this process is accelerated by several ...environmental cues, including exposure to long days. The photoperiod-dependent promotion of flowering involves the transcriptional induction of FLOWERING LOCUS T (FT) in the phloem of the leaf. FT encodes a mobile protein that is transported from the leaves to the shoot apical meristem, where it forms part of a regulatory complex that induces flowering. Whether FT also has biological functions in leaves of wild-type plants remains unclear.
In order to address this issue, we first studied the leaf transcriptomic changes associated with FT overexpression in the companion cells of the phloem. We found that FT induces the transcription of SWEET10, which encodes a bidirectional sucrose transporter, specifically in the leaf veins. Moreover, SWEET10 is transcriptionally activated by long photoperiods, and this activation depends on FT and one of its earliest target genes SUPPRESSOR OF CONSTANS OVEREXPRESSION 1 (SOC1). The ectopic expression of SWEET10 causes early flowering and leads to higher levels of transcription of flowering-time related genes in the shoot apex.
Collectively, our results suggest that the FT-signaling pathway activates the transcription of a sucrose uptake/efflux carrier during floral transition, indicating that it alters the metabolism of flowering plants as well as reprogramming the transcription of floral regulators in the shoot meristem.
A well-defined and very active single-component manganese(II) catalyst system for the hydrosilylation of aldehydes and ketones is presented. First, the reaction of ...5-(2,4,6-iPr3C6H2)-2-N-(2,6-iPr2C6H3)formiminopyrrolyl potassium (KL) and MnCl2(Py)2 afforded the binuclear 2-iminopyrrolyl manganese(II) pyridine chloride complex Mn2{κ2 N,N′-5-(2,4,6-iPr3C6H2)-NC4H2-2-C(H)N(2,6-iPr2C6H3)}2(Py)2(μ-Cl)2 1. Subsequently, the alkylation reaction of complex 1 with LiCH2SiMe3 afforded the respective (trimethylsilyl)methyl-Mn(II) complex Mn{κ2 N,N′-5-(2,4,6-iPr3C6H2)-NC4H2-2-C(H)N(2,6-iPr2C6H3)}(Py)CH2SiMe3 2 in a good yield. Complexes 1 and 2 were characterized by elemental analysis, 1H NMR spectroscopy, Evans’ method, FTIR spectroscopy, and single-crystal X-ray diffraction. While the crystal structure of complex 1 has been identified as a binuclear entity, in which the Mn(II) centers present pentacoordinate coordination spheres, that of complex 2 corresponds to a monomer with a distorted tetrahedral coordination geometry. Complex 2 proved to be a very active precatalyst for the atom-economic hydrosilylation of several aldehydes and ketones under very mild conditions, with a maximum turnover frequency of 95 min–1, via a silyl-Mn(II) mechanistic route, as asserted by a combination of experimental and theoretical efforts, the respective silanes were cleanly converted to the respective alcoholic products in high yields.
This review aims to analyze and synthesize the literature produced so far on investor behavior in the cryptocurrency market. We use VOSviewer 1.6.17 software to perform a bibliometric analysis and ...elaborate a systematic literature review on investor behavior in the cryptocurrency market on a sample of 166 papers published in journals ranked in the ABS 2021 journal list, considering the different fields of knowledge. We found a growing body of literature on the presence of herding behavior in the cryptocurrency market, where there are indications that the main intentions behind crypto investment are mostly affected by social influence or public sentiment; the crypto market is dominated by irrational investors who base their investment decisions on market sentiment; the uncertainty of the fundamentals leads to investors’ dispersed beliefs, which in turn leads to high trading and speculative bubbles. Additionally, we demonstrate some sociodemographic characteristics of crypto investors and some characteristics of the crypto market that affect investors’ behavior, such as market inefficiency. Our study helps researchers and academics, investors, and regulators by providing a structured network analysis for literature strands, with relevant information for future studies on crypto investor behavior. In addition, it shows the most relevant factors that influence the behavior of the crypto market and its investors, providing the basis for better regulation and protection of investors in the cryptocurrency market.
This study contributes to the unconsolidated cryptocurrency literature, with a systematic literature review focused on cryptocurrency market microstructure. We searched Web of Science database and ...focused only on journals listed on 2021 ABS list. Our final sample comprises 138 research papers. We employed a quantitative and an integrative analysis, and revealed complex network associations, and a detailed research trending analysis. Our study provides a robust and systematic contribution to cryptocurrency literature by making use of a powerful and accurate methodology—the bibliographic coupling, also by only considering ABS academic journals, using a wider keyword scope, and not enforcing any restrictions regarding areas of knowledge, thus enhancing the contribution of extant literature by allowing the insights of more high-quality peripheral studies on the subject. The conclusions of this study are of extreme importance for researchers, investors, regulators, and the academic community in general. Our study provides high structured networking and clear information for research outlets and literature strands, for future studies on cryptocurrency investment, it also presents valuable insights to better understand the cryptocurrency market microstructure and deliver helpful information for regulators to effectively regulate cryptocurrencies.
This work reports the first successful isolation and full characterization of cobalt(I) complexes of 5-aryl-2-iminopyrrolyl ligands. In one approach, when Co{κ2 ...N,N′-5-(2,4,6-R3-C6H2)-NC4H2-2-C(H)N(2,6-iPr2-C6H3)}(Py)Cl (R = iPr, 1a; R = Ph, 1b) were reacted with K(HBEt3) or Na(Hg) in toluene, the Co(I) arene complexes Co{κ2 N,N′-5-(2,4,6-iPr3-C6H2)-NC4H2-2-C(H)N(2,6-iPr2-C6H3)}(η6-C6H5CH3) (2a) and Co{κ2 N,N′-5-2′-(κ:η6-C6H5)-C6H2-4′,6′-Ph2-NC4H2-2-C(H)N(2,6-iPr2-C6H3)} (2b) were formed. The reaction of complex 1a with KC8 in Et2O yielded the Co{κ2 N,N′-5-(2,4,6-iPr3-C6H2)-NC4H2-2-C(H)N(2,6-iPr2-C6H3)}2 (3). On another approach, the metathesis of potassium 5-(2,4,6-triisopropylphenyl)-2-(N-2,6-diisopropylphenylformimino)pyrrolyl (KLa) with CoCl(PMe3)3 yielded the bis(trimethylphosphine) complex Co{κ2 N,N′-5-(2,4,6-iPr3-C6H2)-NC4H2-2-C(H)N(2,6-iPr2-C6H3)}(PMe3)2 (4) in a good yield. Complexes 2a, 3, and 4 are paramagnetic, high-spin species, while 2b is a diamagnetic complex. Compound 2b exhibited a spin isomerism behavior (S = 0 ↔ S = 1) as determined by variable-temperature 1H NMR experiments (ΔH° = 7.7 kcal mol–1), being also supported by computational studies (ΔE = 4.2 kcal mol–1). All complexes were tested in the hydroboration of styrene with pinacolborane (HBPin), with complex 4 exclusively yielding the respective anti-Markovnikov addition product. Additionally, all complexes catalyzed the fast and quantitative hydroboration of benzaldehyde with HBPin.
The purpose of this investigation is to analyse the relationship between corporate sustainability disclosure and media visibility, as well as the relative impact of each of these investments on ...perceived quality and electronic popularity in the tourism sector. Therefore, we have identified organizations in the Sustainability Disclosure Database from the Global Reporting Initiative, active in the tourism sector, as well as organizations with hotel properties rated as 2019 Star Award Winners by Forbes Travel Guide, located in one of the twenty most visited cities in the world in 2018. The results show that organizations choose to invest in sustainability disclosure on the expectation of securing an improvement in their media visibility. When they choose to invest in media visibility, organizations do not feel the strategic need to invest in sustainability disclosure. For companies with a higher perceived quality level, investing in sustainability disclosure is not a causal condition. For companies with a higher perceived electronic popularity, the majority continue to invest in media visibility, except public companies that invest in sustainability disclosure instead.
Serine/arginine-rich (SR) proteins are major modulators of alternative splicing, a key generator of proteomic diversity and flexible means of regulating gene expression likely to be crucial in plant ...environmental responses. Indeed, mounting evidence implicates splicing factors in signal transduction of the abscisic acid (ABA) phytohormone, which plays pivotal roles in the response to various abiotic stresses. Using real-time RT-qPCR, we analyzed total steady-state transcript levels of the 18 SR and two SR-like genes from Arabidopsis thaliana in seedlings treated with ABA and in genetic backgrounds with altered expression of the ABA-biosynthesis ABA2 and the ABA-signaling ABI1 and ABI4 genes. We also searched for ABA-responsive cis elements in the upstream regions of the 20 genes. We found that members of the plant-specific SC35-Like (SCL) Arabidopsis SR protein subfamily are distinctively responsive to exogenous ABA, while the expression of seven SR and SR-related genes is affected by alterations in key components of the ABA pathway. Finally, despite pervasiveness of established ABA-responsive promoter elements in Arabidopsis SR and SR-like genes, their expression is likely governed by additional, yet unidentified cis-acting elements. Overall, this study pinpoints SR34, SR34b, SCL30a, SCL28, SCL33, RS40, SR45 and SR45a as promising candidates for involvement in ABA-mediated stress responses.
The borane-functionalized (BR2) bis(3,5-dimethylpyrazolyl)methane (L H ) ligands 1a (BR2: 9-borabicyclo3.3.1nonane or 9-BBN), 1b (BR2: BCy2), and 1c (BR2: B(C6F5)2) were synthesized by the ...allylation–hydroboration of L H . Metalation of 1a,b with ZnCl2 yielded the heteroscorpionate dichloride complexes (1a,b)ZnCl 2 3a,b. The reaction of 1a with ZnEt2 led to the formation of the zwitterionic complex Et(1a)ZnEt(THF) 5. The reaction of complex 3a with two equivalents of KHBEt3 under a carbon dioxide (CO2) atmosphere gave rise to the formation of the dimeric bis(formate) complex (1a)Zn(OCHO) 2 2 8, in which its borane moieties intermolecularly stabilize the formate ligands of opposite metal centers. The allylated precursor L allyl and its zinc dichloride, diethyl and bis(formate) complexes (L allyl )ZnCl 2 2, (L allyl )ZnEt 2 4, and (L allyl )Zn(OCHO) 2 7 were also isolated. The catalyst systems composed of 1 mol % of 3a or 3b and two equivalents of KHBEt3 hydroborated CO2 at 1 bar with pinacolborane (HBPin) to the methanol-level product H3COBPin (and PinBOBPin) in yields of 42 or 86%, respectively. The catalyst systems using the unfunctionalized complex (L H )ZnCl 2 6 and KHBEt3 or KHBEt3/nOctBR2 (BR2: 9-BBN or BCy2) hydroborated CO2 to H3COBPin but in 2.5- to 6-fold lower activities than those exhibited by 3a,b/KHBEt3. The hydroboration of CO2 using 8 as a catalyst led to yields of 39–43%, comparable to those obtained with 3a/KHBEt3. The results confirmed that the catalytic intermediates benefit from the incorporated boranes’ intra- or intermolecular stabilizations.
Cyber-security is the practice of protecting computing systems and networks from digital attacks, which are a rising concern in the Information Age. With the growing pace at which new attacks are ...developed, conventional signature based attack detection methods are often not enough, and machine learning poses as a potential solution. Adversarial machine learning is a research area that examines both the generation and detection of adversarial examples, which are inputs specially crafted to deceive classifiers, and has been extensively studied specifically in the area of image recognition, where minor modifications are performed on images that cause a classifier to produce incorrect predictions. However, in other fields, such as intrusion and malware detection, the exploration of such methods is still growing. The aim of this survey is to explore works that apply adversarial machine learning concepts to intrusion and malware detection scenarios. We concluded that a wide variety of attacks were tested and proven effective in malware and intrusion detection, although their practicality was not tested in intrusion scenarios. Adversarial defenses were substantially less explored, although their effectiveness was also proven at resisting adversarial attacks. We also concluded that, contrarily to malware scenarios, the variety of datasets in intrusion scenarios is still very small, with the most used dataset being greatly outdated.
Our study collected and synthetized the existing knowledge on portfolio diversification, hedge, and safe-haven properties in cryptocurrency investments. We sampled 146 studies published in journals ...ranked in the Association of Business Schools 2021 journals list, considering all fields of knowledge, and elaborated a systematic literature review along with a bibliometric analysis. Our results indicate a fast-growing literature evidencing cryptocurrencies' ability to hedge against stocks, fiat currencies, geopolitical risks, and Economic Policy Uncertainty (EPU) risk; also, that cryptocurrencies present diversification and safe-haven properties; that stablecoins reveal unstable peg with the US dollar; that uncertainty is a determinant for cryptocurrency returns. Additionally, we show that investors should consider Gold, along with the European carbon market, CBOE Bitcoin futures, and crude oil to hedge against unexpected movements in the cryptocurrency market.
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