This paper investigates the impact of a firm’s annual report readability and ambiguous tone on its borrowing costs. We find that firms with larger 10-K file sizes and a higher proportion of uncertain ...and weak modal words in 10-Ks have stricter loan contract terms and greater future stock price crash risk. Our results suggest that the readability and tone ambiguity of a firm’s financial disclosures are related to managerial information hoarding. Shareholders of firms with less readable and more ambiguous annual reports not only suffer from less transparent information disclosure but also bear the increased cost of external financing.
Lithium–sulfur (Li–S) batteries have extremely high theoretical energy density that make them as promising systems toward vast practical applications. Expediting redox kinetics of sulfur species is a ...decisive task to break the kinetic limitation of insulating lithium sulfide/disulfide precipitation/dissolution. Herein, we proposed a porphyrin‐derived atomic electrocatalyst to exert atomic‐efficient electrocatalytic effects on polysulfide intermediates. Quantifying electrocatalytic efficiency of liquid/solid conversion through a potentiostatic intermittent titration technique measurement presents a kinetic understanding of specific phase evolutions imparted by the atomic electrocatalyst. Benefiting from atomically dispersed “lithiophilic” and “sulfiphilic” sites on conductive substrates, the finely designed atomic electrocatalyst endows Li–S cells with remarkable cycling stablity (cyclic decay rate of 0.10% in 300 cycles), excellent rate capability (1035 mAh g−1 at 2 C), and impressive areal capacity (10.9 mAh cm−2 at a sulfur loading of 11.3 mg cm−2). The present work expands atomic electrocatalysts to the Li–S chemistry, deepens kinetic understanding of sulfur species evolution, and encourages application of emerging electrocatalysis in other multielectron/multiphase reaction energy systems.
An atomic‐scale electrocatalyst is proposed to exert atom‐efficiency electrocatalytic effects on polysulfide intermediates in working Li–S batteries. Quantifying electrocatalytic effects on multiphase evolution by kinetic characterizations reveal their unique electrocatalytic benefits on the sulfur conversion reactions, thus enabling impressive battery performances.
Lithium metal is used to achieve high‐energy‐density batteries due to its large theoretical capacity and low negative electrochemical potential. The introduction of quasi‐solid electrolytes ...simultaneously overcomes the safety problems induced by the liquid electrolytes and the high interfacial resistance issues confronted by all solid‐state electrolytes. In‐depth investigations involving interfacial behaviors in quasi‐solid lithium metal batteries are inadequate. Herein an ultrathin Li3OCl quasi‐solid‐state electrolyte layer (500 nm thickness) is used to cover a lithium anode. The polarization of the anode is remarkably reduced by introducing the Li3OCl quasi‐solid‐state electrolyte. In contrast to the decomposition of solvents in a standard electrolyte (EC‐DEC,1.0 m LiPF6), the established quasi‐solid‐state electrolyte interfaces can significantly inhibit the decomposition of solvents when the cut‐off voltage is 4.5 V.
The interfacial behavior of the quasi‐solid‐state electrolyte layer Li3OCl was investigated with a three‐electrode setup. An ultrathin Li3OCl layer can remarkably reduce the over‐potential of the lithium anode and inhibit solvent decomposition, significantly prolonging the service life of a high‐voltage (4.5 V) lithium metal battery.
TMEM173 gene encodes the protein STING (stimulator of interferon genes), a key player in host defense against pathogens. Mutations in the human TMEM173 gene cause a life-threatening auto-inflammatory ...disease called SAVI (STING-associated vasculopathy with onset in infancy). Human STING is also a promising therapeutic target for cancers and infectious diseases. Recently, Aduro Biotech and Novartis announced a $250M-plus initiative to develop STING-targeting cancer immunotherapies. Thus, understanding the genetics of the human TMEM173 gene is important for both basic and translational research. The human TMEM173 gene has great heterogeneity and population stratification. R232 of STING is the most common human TMEM173 allele. However, >50% of Americans are not R232/R232. HAQ (R71H-G230A-R293Q) is the second most common human TMEM173 allele. While R232/R232 is the dominant TMEM173 genotype in Europeans, R232/HAQ is the most common TMEM173 genotype in East Asians. Importantly, recent studies suggested that HAQ and H232 are likely loss-of-function TMEM173 alleles. In all, ~30% of East Asians and ~10% of Europeans are HAQ/HAQ, HAQ/H232, or H232/H232. Here, we reviewed human TMEM173 alleles, mutations and their potential impact on human health and medicine.
Facilitating phase conversion efficiency of Li polysulfides to Li2S and restraining the dissolution of Li polysulfides are critical for stable lithium–sulfur (Li–S) batteries. Herein, an in situ ...formed sulfiphilic superfine Fe2O3 nanocrystals confined in lithiophilic N‐doped microporous carbon (Fe2O3/N‐MC) is derived from one‐step hypercrosslinked polymerization. Uniquely, the dual active sites (Fe2O3 and N) in Fe2O3/N‐MC tend to form “FeS, LiO or LiN” bonding, and then synchronically enhancing the chemisorption and interface conversion ability of Li polysulfides. As a result, 80 wt% S is loaded on Fe2O3/N‐MC and the hybrid cathode delivers high mass capacity (730 mA h g‐1) and excellent cycling stability (87.1% capacity retention over 1000 cycles at 5.0 C). Especially, the cathode also exhibits a high reversible areal capacity of 3.69 mA h cm‐2 at a high areal loading (5.1 mg cm‐2) and a lean electrolyte/sulfur (E/S) ratio (7.5 µL mg‐1) over 500 cycles. This work is anticipated to deepen the comprehension of complex Li polysulfides interphase conversion processes and afford new thoughts for designing new host materials.
Facilitating phase conversion efficiency of Li polysulfides to Li2S and restraining the dissolution of Li polysulfides are critical for stable lithium–sulfur (Li–S) batteries. The as‐prepared Fe2O3/N‐microporous carbon (MC) is in favor of enhancing sulfur content, releasing volume expansion, immobilizing soluble lithium polysulfides (LiPSs), and optimizing Li2S nucleation, hence accommodating the S@Fe2O3/N‐MC cathode with excellent cycling stability.
Big data technique has become a scientific force driving disruptive innovation and change in the education system and the entire field, including English word learning, which will undergo profound ...mechanism changes under the impetus of this trend. The reform of basic English education evaluation in the new era empowered by big data is an inevitable choice to get rid of the chronic problems of the “five-only” education evaluation and to implement the education that builds morality as well as learners’ satisfaction. Traditional classroom teaching is combined with educational information technology to build a smart campus for English education. And data mining hidden educational information and rules are obtained to meet the requirements of students’ personalized learning and other demands. However, the reality is faced with the alienation of the concept of big data in English word learning. Data mining is a very important thinking tool and learning tool, which can help students better learn basic English knowledge, memorize basic words, and improve learning effect. At the same time, it has the effect of cultivating divergent thinking and systematic learning. The foundation of English learning in high school is vocabulary. In order to help students better memorize English vocabulary, teachers can apply mind map associative memory method to implement teaching. In order to solve the problem, this paper proposes the English value concept, constructs a basic education evaluation concept empowered by big data, and eliminates teachers’ concerns about technical ability. We also improve the intellectual support for evaluation reform and reasonably build a data resource platform to meet students’ comprehensive quality evaluation demands. The method accurately conducts the big data evaluation to drive suggestions such as the reconstruction of educational evaluation system.
Owing to the exceptional properties of graphene, intensive studies have been carried out on novel two-dimensional (2D) materials. In the past several years, an elegant exfoliation approach has been ...used to successfully create a new family of 2D transition metal carbides, nitrides, and carbonitrides, termed MXene, from layered MAX phases. More recently, some unique properties of MXene have been discovered leading to proposals of potential applications. In this review, we summarize the latest progress in development of MXene from both a theoretical and experimental view, with emphasis on the possible applications.
The full quantum mechanical (QM) model of inclusive breakup of Ichimura-Austern-Vincent (IAV) is implemented in this paper to calculate breakup from heavy radioactive nuclei on a 9Be target at ...intermediate energies. So far it had been implemented and applied only to low energy reactions with light projectiles. The IAV model is successful in predicting absolute cross sections among other observables. In order to get insight on the content of the model in the case of the complicated heavy-ion reactions, results are compared with those of the semiclassical transfer to the continuum (TC) model. Because the TC is based on analytical formulae the dynamics of the breakup as it is contained in the rather involved IAV formalism will become more transparent. Heavy-ion reactions at high energies (>50 A.MeV) are demanding from the computational point of view because of the high number of partial waves involved, typically around 100. The TC constitutes a useful alternative to the full QM calculations whenever predictions and/or estimates are necessary. It allows also for a systematic, fast evaluation of breakup observables. In the applications of both methods we use state-of-the art optical potentials and structure information. Excellent agreement is found between the calculated results of both methods and with available experimental data which shows that the qualitative and quantitative understanding of most aspects of one nucleon breakup is well under control.
Depression is a common mental disorder characterized by high incidence, high disability, and high fatality, causing great burden to the society, families, and individuals. The changes in brain ...plasticity may be a main reason for depression. Recent studies have shown that exercise plays a positive role in depression, but systematic and comprehensive studies are lacking on brain plasticity changes in depression. To further understand the antidepressive effect of exercise and the changes in brain plasticity, we retrieved related literatures using key words “depression,” “depressive disorder,” “exercise,” “brain plasticity,” “brain structure,” and “brain function” from the database of Web of Science, PubMed, EBSCO host, and CNKI, hoping to provide evidence for exercise in preventing and treating depression. Increase in exercise has been found negatively correlated with the risk of depression. Randomized controlled experiments have shown that aerobic exercise, resistance exercise, and mind‐body exercise can improve depressive symptoms and levels. The intensity and long‐term effect of exercise are now topical research issues. Exercise has been proven to reshape the brain structure of depression patients, activate the function of related brain areas, promote behavioral adaptation changes, and maintain the integrity of hippocampal and white matter volume, thus improving the brain neuroprocessing and delaying cognitive degradation in depression patients. Future studies are urgently needed to establish accurate exercise prescriptions for improving depressive symptoms, and studies on different depressive populations and studies using multimodal brain imaging combined with multiple analytical methods are also needed.
The tuning effect of C3‐ester groups on the glycosylation stereochemistry of L‐rhamnopyranose (L‐Rha) ethyl thioglycoside donors is described. On one hand, the L‐Rha thioglycoside donors carrying ...3‐O‐arylcarbonyl or levulinoyl group undergo highly α‐selective glycosylation to afford a wide variety of α‐L‐rhamnoside products in high chemical yields. On the other hand, the glycosylation of the 3‐O‐4‐nitropicoloyl and 2‐pyrazinecarbonyl group substituted L‐Rha thioglycosides displays β‐stereoselectivity. Only or predominant β anomeric products are obtained when these L‐Rha donors couple with the primary or reactive secondary acceptors, while the β‐selectivity may decrease significantly when these donors react with less reactive secondary alcohols. The synthetic utility of the newly developed α‐ and β‐directing L‐Rha donors 1h and 1e has been demonstrated by the efficient synthesis of a structurally unique trisaccharide 9, which is derived from the cell wall polysaccharide of Sphaerotilus natans.
The tuning effect of C3‐ester groups on the glycosylation stereochemistry of Lrhamnopyranose (L‐Rha) ethyl thioglycosides is described. The 3‐O‐arylcarbonyl or levulinoyl carrying L‐Rha thioglycosides undergo highly α‐selective glycosylation while the glycosylation of the 3‐O‐4‐nitropicoloyl and 2‐pyrazinecarbonyl L‐Rha thioglycosides displays β‐stereoselectivity
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