In experimental research a scientific conclusion is always drawn from the statistical testing of hypothesis, in which an acceptable cutoff of probability, such as 0.05 or 0.01, is used for ...decision-making. However, the probability of committing false statistical inferences would considerably increase when more than one hypothesis is simultaneously tested (namely the multiple comparisons), which therefore requires proper adjustment. Although the adjustment for multiple comparisons is proposed to be mandatory in some journals, it still remains difficult to select a proper method suitable for the various experimental properties and study purposes, especially for researchers without good background in statistics. In the present paper, we provide a brief review on mathematical framework, general concepts and common methods of adjustment for multiple comparisons, which is expected to facilitate the understanding and selection of adjustment methods.
Abstract
Tuning metal–support interaction has been considered as an effective approach to modulate the electronic structure and catalytic activity of supported metal catalysts. At the atomic level, ...the understanding of the structure–activity relationship still remains obscure in heterogeneous catalysis, such as the conversion of water (alkaline) or hydronium ions (acid) to hydrogen (hydrogen evolution reaction, HER). Here, we reveal that the fine control over the oxidation states of single-atom Pt catalysts through electronic metal–support interaction significantly modulates the catalytic activities in either acidic or alkaline HER. Combined with detailed spectroscopic and electrochemical characterizations, the structure–activity relationship is established by correlating the acidic/alkaline HER activity with the average oxidation state of single-atom Pt and the Pt–H/Pt–OH interaction. This study sheds light on the atomic-level mechanistic understanding of acidic and alkaline HER, and further provides guidelines for the rational design of high-performance single-atom catalysts.
Developing red thermally activated delayed fluorescence (TADF) emitters for high‐performance OLEDs is still facing great challenge. Herein, three red TADF emitters, pDBBPZ‐DPXZ, pDTBPZ‐DPXZ, and ...oDTBPZ‐DPXZ, are designed and synthesized with same donor–acceptor (D‐A) backbone with different peripheral groups attaching on the A moieties. Their lowest triplet states change from locally excited to charge transfer character leading to significantly enhance reverse intersystem crossing process. In particular, oDTBPZ‐DPXZ exhibits efficient TADF feature and exciton utilization. It not only achieves an external quantum efficiency (EQE) of 20.1 % in red vacuum‐processed OLED, but also realize a high EQE of 18.5 % in a solution‐processed OLED, which is among the best results in solution‐processed red TADF OLEDs. This work provides an effective strategy for designing red TADF molecules by managing energy level alignments to facilitate the up‐conversion process and thus enhance exciton harvesting.
By introducing phenyl or o‐tolyl groups into different positions of the same acceptor backbone, the lowest triplet energy levels of red thermally activated delayed fluorescence emitters can be tuned from locally excited triplet (3LEA) to charge transfer triplet (3CT) states, resulting in enhancement of the rates of reverse intersystem crossing (RISC), and boosting efficiencies in both vacuum‐ and solution‐processed OLEDs.
Background
With the onset of the coronavirus disease 2019 (COVID‐19) pandemic, many experts expected that asthma‐associated morbidity because of severe acute respiratory syndrome coronavirus 2 ...infection would dramatically increase. However, some studies suggested that there was no apparent increasing in asthma‐related morbidity in children with asthma, it is even possible children may have improved outcomes. To understand the relationship between the COVID‐19 pandemic and asthma outcomes, we performed this article.
Methods
We searched PubMed, Embase, and Cochrane Library to find literature from December 2019 to June 2021 related to COVID‐19 and children's asthma control, among which results such as s, comments, letters, reviews, and case reports were excluded. The level of asthma control during the COVID‐19 pandemic was synthesized and discussed by outcomes of asthma exacerbation, emergency room visit, asthma admission, and childhood asthma control test (c‐ACT).
Results
A total of 22,159 subjects were included in 10 studies. Random effect model was used to account for the data. Compared with the same period before the COVID‐19 pandemic, asthma exacerbation reduced (odds ratio OR = 0.26, 95% confidence interval CI = 0.14–0.48, Z = 4.32, p < 0.0001), the odds of emergency room visit decreased as well (OR = 0.11, 95% CI = 0.04–0.26, Z = 4.98, p < 0.00001). The outcome of asthma admission showed no significant difference (OR = 0.84, 95% CI = 0.32–2.20, Z = 0.36, p = 0.72). The outcome of c‐ACT scores were not analyzed because of the different manifestations used. Overall, c‐ACT scores reduced during the pandemic.
Conclusion
Compared to the same period before the COVID‐19 pandemic, the level of asthma control has been significantly improved. We need to understand the exact factors leading to these improvements and find methods to sustain it.
Room‐temperature phosphorescence (RTP) polymers, whose emission can persist for a long period after photoexcitation, are of great importance for practical applications. Herein, dynamic covalent ...boronic ester linkages with internal B−N coordination are incorporated into a commercial epoxy matrix. The reversible dissociation of B−N bonds upon loading provides an efficient energy dissipation pathway for the epoxy network, while the rigid epoxy matrix can inhibit the quenching of triplet excitons in boronic esters. The obtained polymers exhibit enhanced mechanical toughness (12.26 MJ m−3), ultralong RTP (τ=540.4 ms), and shape memory behavior. Notably, there is no apparent decrease in the RTP property upon prolonged immersion in various solvents because the networks are robust. Moreover, the dynamic bonds endow the polymers with superior reprocessablity and recyclability. These novel properties have led to their potential application for information encryption and anti‐counterfeiting.
Incorporating dynamic covalent boronic ester linkages with internal B−N coordination into a commercial epoxy matrix has led to the fabrication of high‐performance polymer‐based materials with ultralong room‐temperature phosphorescence. The polymers show excellent mechanical properties, environmental stability, shape memory, and recyclability, which could be useful for anticounterfeiting, data encryption, and information editing applications.
Using soy protein isolate (SPI) and soy-soluble polysaccharides (SSPS) as polymer matrixes, this study reported a novel process to fabricate unique core–shell complex (nano)particles to perform as ...carriers for curcumin (a typical poorly soluble bioactive). In the process, curcumin–SPI nanocomplexes were first formed at pH 7.0 and then coated by SSPS. At this pH, the core–shell complex was formed in a way the SPI nanoparticles might be incorporated into the interior of SSPS molecules without distinctly affecting the size and morphology of particles. The core–shell structure was distinctly changed by adjusting pH from 7.0 to 4.0. At pH 4.0, SSPS was strongly bound to the surface of highly aggregated SPI nanoparticles, and as a consequence, much larger complexes were formed. The bioaccessibility of curcumin in the SPI–curcumin complexes was unaffected by the SSPS coating. However, the core–shell complex formation greatly improved the thermal stability and controlled release properties of encapsulated curcumin. The improvement was much better at pH 4.0 than that at pH 7.0. All of the freeze-dried core–shell complex preparations exhibited good redispersion behavior. The findings provide a simple approach to fabricate food-grade delivery systems for improved water dispersion, heat stability, and even controlled release of poorly soluble bioactives.
In the post-industrial period, traditional Chinese enterprises are facing the awkward situation of being 'big but not strong', with their core technologies being controlled by others. The digital ...transformation of enterprises has not only reshaped business models and industrial boundaries, but also boosted the high-quality development of China's economy. This paper reviews the existing literature and discovers that digital technology promotes enterprise production efficiency through cost reduction, efficiency improvement, and innovation. Based on the data of listed manufacturing companies in the Shanghai and Shenzhen stock exchanges from 2009 to 2017, this paper constructs a differences in differences (DID) model to empirically study the relationship between digital transformation and production efficiency. The results revealed that the implementation of digital transformation plays a significant role in promoting economic benefits and the results of the lag regression method are still robust. Based on this, combined with the actual situation of Chinese enterprises, this paper proposes countermeasures and suggestions to promote the development of enterprise digital transformation. The conclusion is of great significance for Chinese enterprises to occupy a dominant position in the new wave of global industrial revolution.
The conformational distribution and mutual interconversion of thermally activated delayed fluorescence (TADF) emitters significantly affect the exciton utilization. However, their influence on the ...photophysics in amorphous film states is still not known due to the lack of a suitable quantitative analysis method. Herein, we used temperature‐dependent time‐resolved photoluminescence spectroscopy to quantitatively measure the relative populations of the conformations of a TADF emitter for the first time. We further propose a new concept of “self‐doping” for realizing high‐efficiency nondoped OLEDs. Interestingly, this “compositionally” pure film actually behaves as a film with a dopant (quasi‐equatorial form) in a matrix (quasi‐axial form). The concentration‐induced quenching that may occur at high concentrations is thus expected to be effectively relieved. The “self‐doping” OLED prepared with the newly developed TADF emitter TP2P‐PXZ as a neat emitting layer realizes a high maximum external quantum efficiency of 25.4 % and neglectable efficiency roll‐off.
Until now, the influence of the conformational distribution on the photophysics and device performance of thermally activated delayed fluorescence (TADF) emitters has not been clear. Herein, conformational populations in disordered solid states are quantitatively measured for the first time. A high‐performance “self‐doping” OLED with a maximum external quantum efficiency of 25.4 % is achieved.
It is widely acknowledged that transcriptional diversity largely contributes to biological regulation in eukaryotes. Since the advent of second-generation sequencing technologies, a large number of ...RNA sequencing studies have considerably improved our understanding of transcriptome complexity. However, it still remains a huge challenge for obtaining full-length transcripts because of difficulties in the short read-based assembly. In the present study we employ PacBio single-molecule long-read sequencing technology for whole-transcriptome profiling in rabbit (Oryctolagus cuniculus). We totally obtain 36,186 high-confidence transcripts from 14,474 genic loci, among which more than 23% of genic loci and 66% of isoforms have not been annotated yet within the current reference genome. Furthermore, about 17% of transcripts are computationally revealed to be non-coding RNAs. Up to 24,797 alternative splicing (AS) and 11,184 alternative polyadenylation (APA) events are detected within this de novo constructed transcriptome, respectively. The results provide a comprehensive set of reference transcripts and hence contribute to the improved annotation of rabbit genome.
Perovskite photovoltaics are strong potential candidates to drive low‐power off‐grid electronics for indoor applications. Compared with rigid devices, flexible perovskite devices can provide a more ...suitable surface for indoor small electronic devices, enabling them have a broader indoor application prospect. However, the mechanical stability of flexible perovskite photovoltaics is an urgent issue solved. Herein, a kind of 3D crosslinking agent named borax is selected to carry out grain boundary penetration treatment on perovskite film to realize full‐dimensional stress release. This strategy improves the mechanical and phase stabilities of perovskite films subjected to external forces or large temperature changes. The fabricated perovskite photovoltaics deliver a champion power conversion efficiency (PCE) of 21.63% under AM 1.5G illumination, which is the highest one to date. The merit of low trap states under weak light makes the devices present a superior indoor PCE of 31.85% under 1062 lux (LED, 2956 K), which is currently the best flexible perovskite indoor photovoltaic device. This work provides a full‐dimensional grain boundary stress release strategy for highly stable flexible perovskite indoor photovoltaics.
A grain boundary stress release strategy is proposed for high‐stability flexible perovskite indoor photovoltaics by the grain boundary penetration with borax 3D stretchable molecules. The full‐dimensional grain boundary stress release enables the flexible perovskite photovoltaics deliver a champion power conversion efficiency (PCE) of 21.63% under AM 1.5G illumination and an indoor PCE of 31.85% under 1062 lux.
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