Predicting protein-ligand binding affinity presents a viable solution for accelerating the discovery of new lead compounds. The recent widespread application of machine learning approaches, ...especially graph neural networks, has brought new advancements in this field. However, some existing structure-based methods treat protein macromolecules and ligand small molecules in the same way and ignore the data heterogeneity, potentially leading to incomplete exploration of the biochemical information of ligands. In this work, we propose LGN, a graph neural network-based fusion model with extra ligand feature extraction to effectively capture local features and global features within the protein-ligand complex, and make use of interaction fingerprints. By combining the ligand-based features and interaction fingerprints, LGN achieves Pearson correlation coefficients of up to 0.842 on the PDBbind 2016 core set, compared to 0.807 when using the features of complex graphs alone. Finally, we verify the rationalization and generalization of our model through comprehensive experiments. We also compare our model with state-of-the-art baseline methods, which validates the superiority of our model. To reduce the impact of data similarity, we increase the robustness of the model by incorporating ensemble learning.
Emotional recognition has arisen as an essential field of study that can expose a variety of valuable inputs. Emotion can be articulated in several means that can be seen, like speech and facial ...expressions, written text, and gestures. Emotion recognition in a text document is fundamentally a content-based classification issue, including notions from natural language processing (NLP) and deep learning fields. Hence, in this study, deep learning assisted semantic text analysis (DLSTA) has been proposed for human emotion detection using big data. Emotion detection from textual sources can be done utilizing notions of Natural Language Processing. Word embeddings are extensively utilized for several NLP tasks, like machine translation, sentiment analysis, and question answering. NLP techniques improve the performance of learning-based methods by incorporating the semantic and syntactic features of the text. The numerical outcomes demonstrate that the suggested method achieves an expressively superior quality of human emotion detection rate of 97.22% and the classification accuracy rate of 98.02% with different state-of-the-art methods and can be enhanced by other emotional word embeddings.
Abstract
Covalent organic frameworks (COFs) have constituted an emerging class of organic photocatalysts showing enormous potential for visible photocatalytic H
2
evolution from water. However, ...suffering from sluggish reaction kinetics, COFs often cooperate with precious metal co-catalysts for essential proton-reducing capability. Here, we synthesize a chiral β-ketoenamine-linked COF coordinated with 10.51 wt% of atomically dispersed Cu(II) as an electron transfer mediator. The enantioselective combination of the chiral COF-Cu(II) skeleton with L-/D-cysteine sacrificial donors remarkably strengthens the hole extraction kinetics, and in turn, the photoinduced electrons accumulate and rapidly transfer via the coordinated Cu ions. Also, the parallelly stacking sequence of chiral COFs provides the energetically favorable arrangement for the H-adsorbed sites. Thus, without precious metal, the visible photocatalytic H
2
evolution rate reaches as high as 14.72 mmol h
−1
g
−1
for the enantiomeric mixtures. This study opens up a strategy for optimizing the reaction kinetics and promises the exciting potential of chiral COFs for photocatalysis.
IMPORTANCE: The increased social and economic burdens for osteoporosis-related fractures worldwide make the prevention of such injuries a major public health goal. Previous studies have reached mixed ...conclusions regarding the association between calcium, vitamin D, or combined calcium and vitamin D supplements and fracture incidence in older adults. OBJECTIVE: To investigate whether calcium, vitamin D, or combined calcium and vitamin D supplements are associated with a lower fracture incidence in community-dwelling older adults. DATA SOURCES: The PubMed, Cochrane library, and EMBASE databases were systematically searched from the inception dates to December 24, 2016, using the keywords calcium, vitamin D, and fracture to identify systematic reviews or meta-analyses. The primary randomized clinical trials included in systematic reviews or meta-analyses were identified, and an additional search for recently published randomized trials was performed from July 16, 2012, to July 16, 2017. STUDY SELECTION: Randomized clinical trials comparing calcium, vitamin D, or combined calcium and vitamin D supplements with a placebo or no treatment for fracture incidence in community-dwelling adults older than 50 years. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers performed the data extraction and assessed study quality. A meta-analysis was performed to calculate risk ratios (RRs), absolute risk differences (ARDs), and 95% CIs using random-effects models. MAIN OUTCOMES AND MEASURES: Hip fracture was defined as the primary outcome. Secondary outcomes were nonvertebral fracture, vertebral fracture, and total fracture. RESULTS: A total of 33 randomized trials involving 51 145 participants fulfilled the inclusion criteria. There was no significant association of calcium or vitamin D with risk of hip fracture compared with placebo or no treatment (calcium: RR, 1.53 95% CI, 0.97 to 2.42; ARD, 0.01 95% CI, 0.00 to 0.01; vitamin D: RR, 1.21 95% CI, 0.99 to 1.47; ARD, 0.00 95% CI, −0.00 to 0.01. There was no significant association of combined calcium and vitamin D with hip fracture compared with placebo or no treatment (RR, 1.09 95% CI, 0.85 to 1.39; ARD, 0.00 95% CI, −0.00 to 0.00). No significant associations were found between calcium, vitamin D, or combined calcium and vitamin D supplements and the incidence of nonvertebral, vertebral, or total fractures. Subgroup analyses showed that these results were generally consistent regardless of the calcium or vitamin D dose, sex, fracture history, dietary calcium intake, and baseline serum 25-hydroxyvitamin D concentration. CONCLUSIONS AND RELEVANCE: In this meta-analysis of randomized clinical trials, the use of supplements that included calcium, vitamin D, or both compared with placebo or no treatment was not associated with a lower risk of fractures among community-dwelling older adults. These findings do not support the routine use of these supplements in community-dwelling older people.
Heterogeneous catalysts offer a cyclable platform for exploring efficient transformation systems, and their promising applications underpin a broad research interest. Covalent organic frameworks ...(COFs) are a class of crystalline porous networks that can integrate organic units into ordered skeletons and pores, offering an insoluble and robust platform for exploring heterogeneous catalysts. In this Outlook, we describe a conceptual scheme for designing catalytic COFs to promote various transformations. We summarize the general strategy for designing COFs to construct tailor-made skeletons and pores by emphasizing their structural uniqueness. We introduce different approaches to develop catalytic functions by sampling COFs into four regimes, i.e., skeletons, walls, pores, and systematically organized systems. We scrutinize their catalytic features and elucidate interplays with electrons, holes, and molecules by highlighting the key role of interface design in exploring catalytic COFs. We further envisage the key issues to be challenged, future research directions, and perspectives to show a full picture of designer heterogeneous catalysis based on COFs.
•The advantages and classifications of S-CO2 cycles are presented.•Applications of cycles especially in nuclear and solar industries are summarized.•The theoretical and experimental analysis of ...system and component are investigated.•The comparison of working fluids and component designs are analyzed.•The challenges to improve the efficiency of S-CO2 cycle applications are concluded.
The development technology and applications of supercritical CO2 power cycle have recently been gaining a lot of attention for applications to different energy industries. The advantage of the S-CO2cycle is high-efficiency within an economic and convenient structure. The stable chemical properties make it be proper to a range of metal material applications. This study provides a detailed comprehensive study of the recent development trends of the S-CO2 power cycle and the different applications of S-CO2 power cycle in various energy industries, especially nuclear energy and solar energy. The theoretical analysis, experimental analysis and the classification of different approaches are summarized for energy sources. The comparison of working fluids, component designs are presented in the article as well. The challenges for improving the efficiency of S-CO2 power cycle applications are analyzed. The study will be a beneficial complement to understanding the recent progress.
Despite considerable advances devoted to improving the operational stability of organic solar cells (OSCs), the metastable morphology degradation remains a challenging obstacle for their practical ...application. Herein, the stabilizing function of the alloy states in the photoactive layer from the perspective of controlling the aggregation characteristics of non‐fullerene acceptors (NFAs), is revealed. The alloy‐like model is adopted separately into host donor and acceptor materials of the state‐of‐the‐art binary PM6:BTP‐4Cl blend with the self‐stable polymer acceptor PDI‐2T and small molecule donor DRCN5T as the third components, delivering the simultaneously enhanced photovoltaic efficiency and storage stability. In such ternary systems, two separate arguments can rationalize their operating principles: (1) the acceptor alloys strengthen the conformational rigidity of BTP‐4Cl molecules to restrain the intramolecular vibrations for rapid relaxation of high‐energy excited states to stabilize BTP‐4Cl acceptor. (2) The donor alloys optimize the fibril network microstructure of PM6 polymer to restrict the kinetic diffusion and aggregation of BTP‐4Cl molecules. According to the superior morphological stability, non‐radiative defect trapping coefficients can be drastically reduced without forming the long‐lived, trapped charge species in ternary blends. The results highlight the novel protective mechanisms of engineering the alloy‐like composites for reinforcing the long‐term stability of NFA‐based ternary OSCs.
The stabilizing function of the alloy states is revealed based on simultaneous efficiency and storage stability boosting in PM6:BTP‐4Cl:PDI‐2T and PM6:DRCN5T:BTP‐4Cl ternary devices. The improved stability can be rationalized by two mechanisms: (1) the acceptor alloys enhance the conformational rigidity of BTP‐4Cl molecules. (2) The donor alloys optimize the fibril network of PM6 to restrict the aggregation of the BTP‐4Cl acceptor.
Phthalates are plasticizers in various products and regarded as endocrine disruptors due to their anti-androgen effects. Environmental occurrence and toxicities of parent phthalates have been widely ...reported, while the current state of knowledge on their metabolites is rarely summarized. Based on the available literature, the present review mainly aims to 1) characterize the potential metabolites of phthalates (mPAEs) using the pharmacokinetics evidences acquired via animal or human models; 2) examine the molecular and cellular mechanism involved in toxicity for mPAEs; 3) investigate the exposure levels of mPAEs in different human specimens (e.g., urine, blood, seminal fluid, breast milk, amniotic fluid and others) across the globe; 4) discuss the models and related parameters for phthalate exposure assessment. We suggest there is subtle difference in toxic mechanisms for mPAEs compared to their parent phthalates due to their alternative chemical structures. Human monitoring studies performed in Asia, America and Europe have provided the population exposure baseline levels for typical phthalates in different regions. Urine is the preferred matrix than other specimens for phthalate exposure study. Among ten urinary mPAEs, the largest proportions of di-(2-ethylhexyl) phthalate (DEHP) metabolites (40%), monoethyl phthalate (mEP) (43%) and DEHP metabolites/mEP (both 29%) were observed in Asia, America and Europe respectively, and mono-5-carboxy-2-ethypentyl phthalate was the most abundant compounds among DEHP metabolites. Daily intakes of phthalates can be accurately calculated via urinary mPAEs if the proper exposure parameters were determined. Further work should focus on combining epidemiological and biological evidences to establish links between phthalates exposure and biological phenotypes. More accurate molar fractions (FUE) of the urinary excreted monoester related to the ingested diesters should be collected in epidemiological or pharmacokinetic studies for different population.
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•Metabolites display different toxic mechanism compared to parent phthalates.•Differences exist in distribution of phthalate metabolites in multiple human specimens.•Urinary profiles of phthalates vary markedly for people on different continents.•Reasonable FUE data are suggested for phthalate exposure assessment by human experiments.
Severe dendrite growth and high‐level activity of the lithium metal anode lead to a short life span and poor safety, seriously hindering the practical applications of lithium metal batteries. With a ...trisalt electrolyte design, an F‐/N‐containing inorganics–rich solid electrolyte interphase on a lithium anode is constructed, which is electrochemically and thermally stable over long‐term cycles and safety abuse conditions. As a result, its Coulombic efficiency can be maintained over 98.98% for 400 cycles. An 85.0% capacity can be retained for coin‐type full cells with a 3.14 mAh cm−2 LiNi0.5Co0.2Mn0.3O2 cathode after 200 cycles and 1.0 Ah pouch‐type full cells with a 4.0 mAh cm−2 cathode after 72 cycles. During the thermal runaway tests of a cycled 1.0 Ah pouch cell, the onset and triggering temperatures were increased from 70.8 °C and 117.4 °C to 100.6 °C and 153.1 °C, respectively, indicating a greatly enhanced safety performance. This work gives novel insights into electrolyte and interface design, potentially paving the way for high‐energy‐density, long‐life‐span, and thermally safe lithium metal batteries.
An F‐/N‐containing inorganics‐rich solid electrolyte interphase is constructed, which is electrochemically and thermally stable during the long‐term cycles and safety abuse conditions. More than 6 times longer cycles compared with routine cells are achieved in 1.0 Ah pouch‐type cells. The onset and triggering temperatures during the thermal runaway are increased from 70.8 and 117.4 to 100.6 and 153.1 °C, respectively.
It is of great significance to depolymerize used or waste polymers to recover the starting monomers suitable for repolymerization reactions that reform recycled materials no different from the virgin ...polymer. Herein, we report a novel recyclable plastic: degradable polycarbonate synthesized by dinuclear chromium‐complex‐mediated copolymerization of CO2 with 1‐benzyloxycarbonyl‐3,4‐epoxy pyrrolidine, a meso‐epoxide. Notably, the novel polycarbonate with more than 99 % carbonate linkages could be recycled back into the epoxide monomer in quantitative yield under mild reaction conditions. Remarkably, the copolymerization/depolymerization processes can be achieved by the ON/OFF reversible temperature switch, and recycled several times without any change in the epoxide monomer and copolymer. These characteristics accord well with the concept of perfectly sustainable polymers.
A sustainable plastic was synthesized by dinuclear chromium‐complex‐mediated copolymerization of CO2 with an epoxide that could be recycled back into the monomer in quantitative yield under mild conditions. Temperature was used as a reversible switch in the recycle process. These characteristics are in accordance with the concept of perfectly sustainable polymers.
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