Abstract
The colour gamut, a two-dimensional (2D) colour space primarily comprising hue and saturation (HS), lays the most important foundation for the colour display and printing industries. ...Recently, the metasurface has been considered a promising paradigm for nanoprinting and holographic imaging, demonstrating a subwavelength image resolution, a flat profile, high durability, and multi-functionalities. Much effort has been devoted to broaden the 2D HS plane, also known as the CIE map. However, the brightness (B), as the carrier of chiaroscuro information, has long been neglected in metasurface-based nanoprinting or holograms due to the challenge in realising arbitrary and simultaneous control of full-colour HSB tuning in a passive device. Here, we report a dielectric metasurface made of crystal silicon nanoblocks, which achieves not only tailorable coverage of the primary colours red, green and blue (RGB) but also intensity control of the individual colours. The colour gamut is hence extruded from the 2D CIE to a complete 3D HSB space. Moreover, thanks to the independent control of the RGB intensity and phase, we further show that a single-layer silicon metasurface could simultaneously exhibit arbitrary HSB colour nanoprinting and a full-colour hologram image. Our findings open up possibilities for high-resolution and high-fidelity optical security devices as well as advanced cryptographic approaches.
Potassium and nitrogen are essential macronutrients for plant growth and have a positive impact on crop yield. Previous studies have indicated that the absorption and translocation of K+ and NO3
− ...are correlated with each other in plants; however, the molecular mechanism that coordinates K+ and NO3
− transport remains unknown. In this study, using a forward genetic approach, we isolated a low-K+-sensitive Arabidopsis thaliana mutant, lks2, that showed a leaf chlorosis phenotype under low-K+ conditions. LKS2 encodes the transporter NRT1.5/NPF7.3, a member of the NRT1/PTR (Nitrate Transporter 1/Peptide Transporter) family. The lks2/nrt1.5 mutants exhibit a remarkable defect in both K+ and NO3
− translocation from root to shoot, especially under low-K+ conditions. This study demonstrates that LKS2 (NRT1.5) functions as a proton-coupled H+/K+ antiporter. Proton gradient can promote NRT1.5-mediated K+ release out of root parenchyma cells and facilitate K+ loading into the xylem. This study reveals that NRT1.5 plays a crucial role in K+ translocation from root to shoot and is also involved in the coordination of K+/NO3
− distribution in plants.
Purpose
To investigate the role of computed tomography (CT) radiomics for the preoperative prediction of lymph node (LN) metastasis in gastric cancer.
Materials and methods
This retrospective study ...included 247 consecutive patients (training cohort, 197 patients; test cohort, 50 patients) with surgically proven gastric cancer. Dedicated radiomics prototype software was used to segment lesions on preoperative arterial phase (AP) CT images and extract features. A radiomics model was constructed to predict the LN metastasis by using a random forest (RF) algorithm. Finally, a nomogram was built incorporating the radiomics scores and selected clinical predictors. Receiver operating characteristic (ROC) curves were used to validate the capability of the radiomics model and nomogram on both the training and test cohorts.
Results
The radiomics model showed a favorable discriminatory ability in the training cohort with an area under the curve (AUC) of 0.844 (95% CI, 0.759 to 0.909), which was confirmed in the test cohort with an AUC of 0.837 (95% CI, 0.705 to 0.926). The nomogram consisted of radiomics scores and the CT-reported LN status showed excellent discrimination in the training and test cohorts with AUCs of 0.886 (95% CI, 0.808 to 0.941) and 0.881 (95% CI, 0.759 to 0.956), respectively.
Conclusions
The CT-based radiomics nomogram holds promise for use as a noninvasive tool in the individual prediction of LN metastasis in gastric cancer.
Key Points
• CT radiomics showed a favorable performance for the prediction of LN metastasis in gastric cancer.
• Radiomics model outperformed the routine CT in predicting LN metastasis in gastric cancer.
• The radiomics nomogram holds potential in the individualized prediction of LN metastasis in gastric cancer.
The 4+3 annulation of aza‐o‐quinone methides and pyridinium 1,4‐zwitterionic thiolates has been developed for the one‐step synthesis of functionalized 2,3‐unsaturated 4,1‐benzothiazepines under mild ...and metal‐free conditions. The produced 4,1‐benzothiazepines can easily be converted into biologically interesting sulfoxides and sulfones via selective oxidization with m‐CPBA.
Functional textiles are ideal substrates for wearable electronics. Herein, superhydrophobic, flame-retardant and conductive cotton fabrics were fabricated by sequential assembly of ...poly(ethylenimine), ammonium polyphosphate and carbon nanotubes, followed by post-treatment with poly(dimethylsiloxane). The resulting fabrics possessed excellent superhydrophobic stability toward acid, alkali, organic solvent, UV irradiation, abrasion and long-time laundering. Meanwhile, when suffering to fire, the coated fabric could generate an efficient char layer and extinguish the fire to protect the cotton fiber from forming flame. Furthermore, this conductive cotton fabric exhibited stable sensing ability in contact with water droplets, showing wide potential application in wearable electronics as multifunctional smart textiles.
Light‐harvesting complexes (LHC) in photosynthetic organisms perform the major function of light absorption and energy transportation. Optical spectrum of LHC provides a detailed understanding of the ...molecular mechanisms involved in the excitation energy transfer (EET) processes, which has been widely studied. Here, we study how the geometric property of LHC in Rhodospirillum (Rs.) molischianum would affect its spectral characteristics and energy transfer process. By adopting the effective Hamiltonian and the dipole–dipole approximation, we calculate the exciton level structures for the LH2 ring and LH1 ring and the energy transfer time between different LHCs under various structural parameters and different rotational symmetries. Our numerical results show that the LHC's absorption peaks and the energy transfer time between different LHCs can be modified by changing the geometric configurations. Our study may be beneficial to the applications in designing highly efficient photovoltaic cell and other artificial photosynthetic systems.
Light‐harvesting complexes (LHC) in photosynthetic organisms perform the major function of light absorption and energy transportation. We construct a geometric model of Rs. Molischianumin in which the geometric parameters such as ring diameter, fold symmetry order and dipole directions can be modified. We study how the absorption spectrum and energy transfer rate of the LHC depend on different geometric parameters. Our results here may find applications in designing highly efficient photovoltaic cell and other artificial photosynthetic systems.
The COVID-19 outbreak has affected people's health worldwide. For college students, web-based physical education is a challenge, as these course are normally offered outdoors.
The aim of this study ...was to use data from a web-based survey to evaluate the relationship between the mental health status of college students and their sports-related lifestyles. Problems related to web-based physical education were also examined.
A web-based survey was conducted by snowball sampling from May 8 to 11, 2020. Demographic data, mental health status, and sports-related lifestyles of college students in Wuhan as well as issues related to web-based physical education were collected. Mental health status was assessed by the Depression, Anxiety, and Stress Scale (DASS-21).
The study included 1607 respondents from 267 cities. The average scores of the DASS-21 subscales (2.46 for depression, 1.48 for anxiety, and 2.59 for stress) were significantly lower in our study than in a previous study (P<.05). Lower DASS-21 scores were significantly correlated with regular exercise, maintaining exercise habits during the outbreak of COVID-19, exercising more than 1 to 2 times a week, exercise duration >1 hour, and >2000 pedometer steps (all P<.05). None of the three forms of web-based physical education was preferred by more than 50% of respondents. Frequent technical problems were confronted by 1087/1607 students (67.6%). Shape-up exercises (846/1607, 52.6%), a designed combination of exercises (710/1607, 44.2%), and Chinese kung fu (559/1607, 34.8%) were suggested sports for web-based physical education.
Mental status was significantly correlated with regular exercise and sufficient exercise duration. Professional physical guidance is needed for college students in selected sports. Exercises not meeting students' preferences, frequent technical problems, and the distant interaction involved in web-based physical education were the main problems that should be solved in future.
The use of dicyanometalate precursor
trans-M
A(L)(CN)
2
n
,
cis-M
A(L)(CN)
2
n
or Co(triphos)(CN)
2 in reactions with M
BL
x
L′
y
m+
has yielded a number of clusters containing di-, tri-, tetra-, ...dodecanuclear clusters and various
nD assemblies (
n
=
1–3).
Display omitted
►
trans-M
A(L)(CN)
2
n
,
cis-M
A(L)(CN)
2
n
and Co(triphos)(CN)
2 as dicyanometalate precursors. ► Dicyanometalate precursors result in clusters and
nD assemblies (
n
=
1–3). ► Cyano-bridged compounds with various structures and magnetic/spectroscopic properties ► The magnetic/spectroscopic properties are related with the structural topologies.
Cyanide-bridged molecule-based magnetic materials with reduced dimensionality, such as single-molecule magnets (SMMs) and single-chain magnets (SCMs), have attracted great research interest during the last decade. Among the cyanide-based molecular precursors with ample coordinating capability, we note the ability of the dicyanometalate M
A(L)(CN)
2
n
(M
A
=
Fe
III/II, Ru
III/II, Os
III/II, Co
II, Cr
III;
n
=
−1, 0, +1; L
=
polydentate blocking ligand) to link various metal ions leads to a wide diversity of structural architectures ranging from discrete polynuclear complexes to various one-dimensional (1D), two-dimensional (2D) and three-dimensional (3D) assemblies. Some of these are promising cyanide-bridged SMMs, SCMs, switchable molecular materials or chemosensors with good light absorbing properties. The use of blocking tetradentate organic ligands results in a number of polynuclear compounds containing di-, tri-, tetra-, dodecanuclear and multidimensional metal-cyanide architectures. Here we review the structural topologies of these complexes and their related magnetic, spectroscopic properties, highlight typical examples, and point out the main possible directions that remain to be developed in this field. From the crystal engineering point of view, the compounds reviewed here should provide useful information for further design and investigation on this elusive class of dicyanometalte-bearing compounds.
•Effect of H2S on the corrosion behaviour of HEA was investigated.•Pseudo-passivation of HEA in the H2S-containing environment was first found.•Formation of Cr substances resulted in the transition ...from active to pseudo-passive corrosion.•Pseudo-passivation mechanism of HEA in H2S environments was discussed.
The pseudo-passivation mechanism of CoCrFeNiMo0.01 high-entropy alloy (HEA) in H2S-containing acid solutions was investigated. The results showed that HEA displayed pseudo-passive behaviour in the H2S environment. The reduction reactions of H2S and HS− occurred, leading to a diffusion-controlled region in the cathodic polarization curve. The massive formation of Cr substances on HEA resulted in the transition from active to pseudo-passive corrosion. The film broke down at high potential due to the instability of sulphides. The pseudo-passivation mechanism of HEA in H2S environments was discussed.
While protein coronas (PCs) are an important barrier in the clinical application of nanomedicines, the specific effects of PCs on nanoparticles (NPs) in vivo are unclear. Herein, we demonstrated that ...PCs from clinical sources greatly influenced the active targeting capacities of transferrin-modified NPs (Tf-NPs). Compared to PCs from healthy volunteers, PCs from the plasma of patients with nonsmall cell lung cancer (NSCLC) decreased the A549 uptake of Tf-NPs to a greater degree. The PC proteome revealed that this difference may be mediated by certain proteins in plasma. To attenuate the negative influence of PCs from patients, precoating Tf-NPs with PCs derived from healthy mice significantly enhanced active targeting capacities. Paclitaxel-loaded Tf-NPs with PCs derived from healthy mice showed the strongest antitumor effects in mice with NSCLC. This work illustrates the influence of PCs of ligand-modified NPs in clinical practice and proposes the use of corona-enabled active targeting for precision nanomedicine.
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