There is a growing need for energy storage devices in numerous applications where a large amount of energy needs to be either stored or delivered quickly. The present paper details the study of ...alkali-ion intercalation pseudocapacitance in ultrathin VOPO4 nanosheets, which hold promise in high-rate alkali-ion based electrochemical energy storage. Starting from bulk VOPO4·2H2O chunks, VOPO4 nanosheets were obtained through simple ultrasonication in 2-propanol. These nanosheets as the cathode exhibit a specific capacity of 154 and 136 mAh/g (close to theoretical value 166 mAh/g) for lithium and sodium storage devices at 0.1 C and 100 and ∼70 mAh/g at 5 C, demonstrating their high rate capability. Moreover, the capacity retention is maintained at 90% for lithium ion storage and 73% for sodium ion storage after 500 cycles, showing their reasonable stability. The demonstrated alkali-ion intercalation pseudocapacitance represents a promising direction for developing battery materials with promising high rate capability.
2D nanomaterials provide numerous fascinating properties, such as abundant active surfaces and open ion diffusion channels, which enable fast transport and storage of lithium ions and beyond. ...However, decreased active surfaces, prolonged ion transport pathway, and sluggish ion transport kinetics caused by self‐restacking of 2D nanomaterials during electrode assembly remain a major challenge to build high‐performance energy storage devices with simultaneously maximized energy and power density as well as long cycle life. To address the above challenge, porosity (or hole) engineering in 2D nanomaterials has become a promising strategy to enable porous 2D nanomaterials with synergetic features combining both 2D nanomaterials and porous architectures. Herein, recent important progress on porous/holey 2D nanomaterials for electrochemical energy storage is reviewed, starting with the introduction of synthetic strategies of porous/holey 2D nanomaterials, followed by critical discussion of design rule and their advantageous features. Thereafter, representative work on porous/holey 2D nanomaterials for electrochemical capacitors, lithium‐ion and sodium‐ion batteries, and other emerging battery technologies (lithium‐sulfur and metal‐air batteries) are presented. The article concludes with perspectives on the future directions for porous/holey 2D nanomaterial in energy storage and conversion applications.
Holey 2D nanomaterials have shown great promise to address several key challenges of decreased active surfaces, prolonged ion transport pathway, and sluggish ion transport kinetics caused by self‐restacking of 2D materials. Recent progress of porous 2D nanomaterials, in terms of the synthetic strategies and their applications in electrochemical energy storage, as well as the future development are summarized.
Research on 2D nanomaterials is rising to an unprecedented height and will continue to remain a very important topic in materials science. In parallel with the discovery of new candidate materials ...and exploration of their unique characteristics, there are intensive interests to rationally control and tune the properties of 2D nanomaterials in a predictable manner. Considerable attention is focused on modifying these materials structurally or engineering them into designed architectures to meet requirements for specific applications. Recent advances in such structural engineering strategies have demonstrated their ability to overcome current material limitations, showing great promise for promoting device performance to a new level in many energy‐related applications. Existing in many forms, these strategies can be categorized based on how they intrinsically or extrinsically alter the pristine structure. Achieved through various synthetic routes and practiced in a range of different material systems, they usually share common descriptors that predestine them to be effective in certain circumstances. Therefore, understanding the underlying mechanism of these strategies to provide fundamental insights into structural design and property tailoring is of critical importance. Here, the most recent development of structural engineering of 2D nanomaterials and their significant effects in energy storage and catalysis technologies are addressed.
Structural engineering serves as an important material design concept and offers new inroads into the field of 2D nanomaterials, including both conventional material engineering methods and novel nanotechnology approaches. Recent progress of structural engineering strategies for 2D nanomaterials and their implications for advanced energy storage and catalysis technologies are presented.
Purpose
Segmentation of pulmonary nodules is critical for the analysis of nodules and lung cancer diagnosis. We present a novel framework of segmentation for various types of nodules using ...convolutional neural networks (CNNs).
Methods
The proposed framework is composed of two major parts. The first part is to increase the variety of samples and build a more balanced dataset. A conditional generative adversarial network (cGAN) is employed to produce synthetic CT images. Semantic labels are generated to impart spatial contextual knowledge to the network. Nine attribute scoring labels are combined as well to preserve nodule features. To refine the realism of synthesized samples, reconstruction error loss is introduced into cGAN. The second part is to train a nodule segmentation network on the extended dataset. We build a three‐dimensional (3D) CNN model that exploits heterogeneous maps including edge maps and local binary pattern maps. The incorporation of these maps informs the model of texture patterns and boundary information of nodules, which assists high‐level feature learning for segmentation. Residual unit, which learns to reduce residual error, is adopted to accelerate training and improve accuracy.
Results
Validation on LIDC‐IDRI dataset demonstrates that the generated samples are realistic. The mean squared error and average cosine similarity between real and synthesized samples are 1.55×10−2 and 0.9534, respectively. The Dice coefficient, positive predicted value, sensitivity, and accuracy are, respectively, 0.8483, 0.8895, 0.8511, and 0.9904 for the segmentation results.
Conclusions
The proposed 3D CNN segmentation framework, based on the use of synthesized samples and multiple maps with residual learning, achieves more accurate nodule segmentation compared to existing state‐of‐the‐art methods. The proposed CT image synthesis method can not only output samples close to real images but also allow for stochastic variation in image diversity.
State‐of‐the‐art energy storage devices are capable of delivering reasonably high energy density (lithium ion batteries) or high power density (supercapacitors). There is an increasing need for these ...power sources with not only superior electrochemical performance, but also exceptional flexibility. Graphene has come on to the scene and advancements are being made in integration of various electrochemically active compounds onto graphene or its derivatives so as to utilize their flexibility. Many innovative synthesis techniques have led to novel graphene‐based hybrid two‐dimensional nanostructures. Here, the chemically integrated inorganic‐graphene hybrid two‐dimensional materials and their applications for energy storage devices are examined. First, the synthesis and characterization of different kinds of inorganic‐graphene hybrid nanostructures are summarized, and then the most relevant applications of inorganic‐graphene hybrid materials in flexible energy storage devices are reviewed. The general design rules of using graphene‐based hybrid 2D materials for energy storage devices and their current limitations and future potential to advance energy storage technologies are also discussed.
Chemically integrated inorganic‐graphene two‐dimensional hybrid materials have gained growing interest as promising electrodes for energy storage devices with not only superior electrochemical performance, but also exceptional flexibility. Different kinds of inorganic‐graphene hybrid nanostructures for flexible energy storage devices are comprehensively discussed, in terms of the general design rule, current limitations and future potential to advance energy storage technologies.
Lithium‐ion batteries (LIBs) have dominated the portable electronics industry and solid‐state electrochemical research and development for the past two decades. In light of possible concerns over the ...cost and future availability of lithium, sodium‐ion batteries (SIBs) and other new technologies have emerged as candidates for large‐scale stationary energy storage. Research in these technologies has increased dramatically with a focus on the development of new materials for both the positive and negative electrodes that can enhance the cycling stability, rate capability, and energy density. Two‐dimensional (2D) materials are showing promise for many energy‐related applications and particularly for energy storage, because of the efficient ion transport between the layers and the large surface areas available for improved ion adsorption and faster surface redox reactions. Recent research highlights on the use of 2D materials in these future ‘beyond‐lithium‐ion’ battery systems are reviewed, and strategies to address challenges are discussed as well as their prospects.
Two‐dimensional nanomaterials have gained growing interest as promising candidates for electrode materials for lithium ion batteries and beyond. Various kinds of two‐dimensional nanomaterials for sodium ion batteries and other emerging battery technologies are summarized, along with the current difficulties and potential strategies. Perspectives on the future development of two‐dimensional nanomaterials as beyond‐Li‐ion energy storage electrodes are presented.
The incidence of sleep deprivation is increasing year by year and people are also paying more attention to the effects of sleep deprivation on the human body and on cognition. In addition, working ...memory is the foundation of many advanced cognitive functions. Therefore, we reviewed, herein, the relevant research literature on the influence of sleep deprivation on working memory, the relevant influencing factors, and possible mechanisms of action, intending to acquire a more thorough understanding of the effects of sleep deprivation on working memory and to provide evidence for scientific and sound strategies of sleep.
We report to use the main protease (M
) of SARS-Cov-2 to screen plant flavan-3-ols and proanthocyanidins. Twelve compounds, (-)-afzelechin (AF), (-)-epiafzelechin (EAF), (+)-catechin (CA), ...(-)-epicatechin (EC), (+)-gallocatechin (GC), (-)-epigallocatechin (EGC), (+)-catechin-3-O-gallate (CAG), (-)-epicatechin-3-O-gallate (ECG), (-)-gallocatechin-3-O-gallate (GCG), (-)-epigallocatechin-3-O-gallate (EGCG), procyanidin A2 (PA2), and procyanidin B2 (PB2), were selected for docking simulation. The resulting data predicted that all 12 metabolites could bind to M
. The affinity scores of PA2 and PB2 were predicted to be -9.2, followed by ECG, GCG, EGCG, and CAG, -8.3 to -8.7, and then six flavan-3-ol aglycones, -7.0 to -7.7. Docking characterization predicted that these compounds bound to three or four subsites (S1, S1', S2, and S4) in the binding pocket of M
via different spatial ways and various formation of one to four hydrogen bonds.
analysis with 10 available compounds showed that CAG, ECG, GCG, EGCG, and PB2 inhibited the M
activity with an IC
value, 2.98 ± 0.21, 5.21 ± 0.5, 6.38 ± 0.5, 7.51 ± 0.21, and 75.3 ± 1.29 μM, respectively, while CA, EC, EGC, GC, and PA2 did not have inhibitory activities. To further substantiate the inhibitory activities, extracts prepared from green tea (GT), two muscadine grapes (MG), cacao, and dark chocolate (DC), which are rich in CAG, ECG, GAG, EGCG, or/and PB2, were used for inhibitory assay. The resulting data showed that GT, two MG, cacao, and DC extracts inhibited the M
activity with an IC
value, 2.84 ± 0.25, 29.54 ± 0.41, 29.93 ± 0.83, 153.3 ± 47.3, and 256.39 ± 66.3 μg/ml, respectively. These findings indicate that on the one hand, the structural features of flavan-3-ols are closely associated with the affinity scores; on the other hand, the galloylation and oligomeric types of flavan-3-ols are critical in creating the inhibitory activity against the M
activity.
Breast cancer, characterized by its molecular intricacy, has witnessed a surge in targeted therapeutics owing to the rise of small-molecule drugs. These entities, derived from cutting-edge synthetic ...routes, often encompassing multistage reactions and chiral synthesis, target a spectrum of oncogenic pathways. Their mechanisms of action range from modulating hormone receptor signaling and inhibiting kinase activity, to impeding DNA damage repair mechanisms. Clinical applications of these drugs have resulted in enhanced patient survival rates, reduction in disease recurrence, and improved overall therapeutic indices. Notably, certain molecules have showcased efficacy in drug-resistant breast cancer phenotypes, highlighting their potential in addressing treatment challenges. The evolution and approval of small-molecule drugs have ushered in a new era for breast cancer therapeutics. Their tailored synthetic pathways and defined mechanisms of action have augmented the precision and efficacy of treatment regimens, paving the way for improved patient outcomes in the face of this pervasive malignancy. The present review embarks on a detailed exploration of small-molecule drugs that have secured regulatory approval for breast cancer treatment, emphasizing their clinical applications, synthetic pathways, and distinct mechanisms of action.
Background
This study aimed to summarize the association between diabetes mellitus (DM) and the incidence of lung cancer using a meta‐analysis of cohort studies.
Materials and methods
We ...systematically searched PubMed, Embase and the Cochrane Library to identify potential cohort studies. Relative risk (RR) was used to calculate the association between DM and the risk of lung cancer. Subgroup analysis, sensitivity analysis and test for publication bias were performed. Twenty cohort studies were selected.
Results
The participants with DM showed little or no significant effect on the risk of lung cancer (RR: 1.10; 95% CI: 0.99‐1.23; P = .087). DM was not associated with the risk of lung cancer in men (RR: 1.11; 95%CI: 0.92‐1.35; P = .270), but a significant association was observed in women (RR: 1.18; 95%CI: 1.10‐1.28; P < .001). Subgroup analysis suggested that smoker status was confounding variables that could bias the relationship between DM and the incidence of lung cancer.
Conclusions
This meta‐analysis suggests that DM has no significant impact on the incidence of lung cancer in men but has a harmful effect on women.
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