Abstract
Photocatalytic formation of hydrocarbons using solar energy via artificial photosynthesis is a highly desirable renewable-energy source for replacing conventional fossil fuels. Using an
l
...-cysteine-based hydrothermal process, here we synthesize a carbon-doped SnS
2
(SnS
2
-C) metal dichalcogenide nanostructure, which exhibits a highly active and selective photocatalytic conversion of CO
2
to hydrocarbons under visible-light. The interstitial carbon doping induced microstrain in the SnS
2
lattice, resulting in different photophysical properties as compared with undoped SnS
2
. This SnS
2
-C photocatalyst significantly enhances the CO
2
reduction activity under visible light, attaining a photochemical quantum efficiency of above 0.7%. The SnS
2
-C photocatalyst represents an important contribution towards high quantum efficiency artificial photosynthesis based on gas phase photocatalytic CO
2
reduction under visible light, where the in situ carbon-doped SnS
2
nanostructure improves the stability and the light harvesting and charge separation efficiency, and significantly enhances the photocatalytic activity.
Floral homeotic transcription factors (TFs) act in a combinatorial manner to specify the organ identities in the flower. However, the architecture and the function of the gene regulatory network ...(GRN) controlling floral organ specification is still poorly understood. In particular, the interconnections of homeotic TFs, microRNAs (miRNAs) and other factors controlling organ initiation and growth have not been studied systematically so far. Here, using a combination of genome-wide TF binding, mRNA and miRNA expression data, we reconstruct the dynamic GRN controlling floral meristem development and organ differentiation. We identify prevalent feed-forward loops (FFLs) mediated by floral homeotic TFs and miRNAs that regulate common targets. Experimental validation of a coherent FFL shows that petal size is controlled by the SEPALLATA3-regulated miR319/TCP4 module. We further show that combinatorial DNA-binding of homeotic factors and selected other TFs is predictive of organ-specific patterns of gene expression. Our results provide a valuable resource for studying molecular regulatory processes underlying floral organ specification in plants.
Very recently, the LHCb collaboration has observed in the final state
Λ
c
+
K
-
π
+
π
+
a resonant structure that is identified as the doubly charmed baryon
Ξ
cc
+
+
. Inspired by this observation, ...we investigate the weak decays of doubly heavy baryons
Ξ
cc
+
+
,
Ξ
cc
+
,
Ω
cc
+
,
Ξ
bc
(
′
)
+
,
Ξ
bc
(
′
)
0
,
Ω
bc
(
′
)
0
,
Ξ
bb
0
,
Ξ
bb
-
and
Ω
bb
-
and focus on the decays into spin 1 / 2 baryons in this paper. At the quark level these decay processes are induced by the
c
→
d
/
s
or
b
→
u
/
c
transitions, and the two spectator quarks can be viewed as a scalar or axial vector diquark. We first derive the hadronic form factors for these transitions in the light-front approach and then apply them to predict the partial widths for the semileptonic and nonleptonic decays of doubly heavy baryons. We find that the number of decay channels is sizable and can be examined in future measurements at experimental facilities like LHC, Belle II and CEPC.
Cathodes in lithium‐ion batteries with anionic redox can deliver extraordinarily high specific capacities but also present many issues such as oxygen release, voltage hysteresis, and sluggish ...kinetics. Identifying problems and developing solutions for these materials are vital for creating high‐energy lithium‐ion batteries. Herein, the electrochemical and structural monitoring is conducted on lithium‐rich cathodes to directly probe the formation processes of larger voltage hysteresis. These results indicate that the charge‐compensation properties, structural evolution, and transition metal (TM) ions migration vary from oxidation to reduction process. This leads to huge differences in charge and discharge voltage profile. Meanwhile, the anionic redox processes display a slow kinetics process with large hysteresis (≈0.5 V), compared to fast cationic redox processes without any hysteresis. More importantly, a simple yet effective strategy has been proposed where fine‐modulating local oxygen environment by the lithium/oxygen (Li/O) ratio tunes the anionic redox chemistry. This effectively improves its electrochemical properties, including the operating voltage and kinetics. This is also verified by theoretical calculations that adjusting anionic redox chemistry by the Li/O ratio shifts the TM 3d—O 2p bands and the non‐bonding O 2p band to a lower energy level, resulting in a higher redox reaction potential.
The relationship between voltage hysteresis and anion/cation redox, structure evolution, and transition metal ions migration have been detailed and identified using electrochemical and structural monitoring. Based on the guidance of the analysis, the large voltage hysteresis can be mitigated by modulating the anion/cation redox (by only adjusting the lithium/oxygen ratio).
An injectable, self‐healing hydrogel (≈1.5 kPa) is developed for healing nerve‐system deficits. Neurosphere‐like progenitors proliferate in the hydrogel and differentiate into neuron‐like cells. In ...the zebrafish injury model, the central nervous system function is partially rescued by injection of the hydrogel and significantly rescued by injection of the neurosphere‐laden hydrogel. The self‐healing hydrogel may thus potentially repair the central nervous system.
The solar magnetic activity cycle has a profound impact on our lives, yet its underlying causes remain elusive. While similar cycles have been observed in other stars, these results are scarce due to ...the significant challenge posed by the length of time required for observation. Continuous observation over an extended period is a luxury, making it difficult to gather large samples. However, multiple random observations can be made at a lower cost, and flexible time management enables non-professionals to become competent. In this study, we analyzed multiple random observations of the S-indices of several stars captured incidentally by the Large Sky Area Multi-Object Fiber Spectroscopic Telescope. Our findings reveal potential periodicity that could be associated with magnetic activity cycles. Notably, obtaining S-index is relatively less challenging, indicating the feasibility of developing dedicated commercial or charitable equipment for non-astronomers. A more extensive data is essential to establish a definitive correlation between S-index periodicity and magnetic activity cycles in stars, as well as to uncover additional magnetic activity cycles.
Substrate‐supported metal–organic frameworks (MOFs) films are desired to realize their potential in practical applications. Herein, a novel substrate‐seeding secondary‐growth strategy is developed to ...prepare composites of uniform MOFs films on aerogel walls. Briefly, the organic ligand is “pre‐seeded” onto the aerogel walls, and then a small amount of metal‐ion solution is sprayed onto the prepared aerogel. The sprayed solution diffuses along the aerogel walls to form a continuous thin layer, which confines the nucleation reaction, promoting the formation of uniform MOFs films on the aerogel walls. The whole process is simple in operation, highly efficient, and eco‐friendly. The resulting hierarchical MOFs/aerogel composites have abundant accessible active sites and enable excellent mass transfer, which endows the composite with outstanding catalytic activity and stability in both liquid‐phase CO2 cycloaddition and electrochemical oxygen evolution reaction (OER) process.
Metal–organic framework (MOF) thin films are coated onto the walls of aerogel giving MOFs/aerogel composites. These have abundant accessible active sites and excellent mass transfer ability, and thus a relatively high catalytic activity and stability in the CO2 cycloaddition and oxygen evolution reaction (OER).
Titania nanotubes grown by anodic oxidation have intrigued the material science community by its many unique and potential properties, and the synthesis of technology is merging to its mature stage. ...The present review will focus on TiO
2
nanotubes grown by self-organized electrochemical anodization from Ti metal substrate, which critically highlights the synthesis of this type of self-organized titania nanotube layers and the means to influence the size, shape, the degree of order, and crystallized phases via adjusting the anodization parameters and the subsequent thermal annealing. The relationship between dimensions and properties of the anodic TiO
2
nanotube arrays will be presented. The latest progress and significance of the research on formation mechanism of anodic TiO
2
nanotubes are briefly discussed. Besides, we will show the most promising applications reported recently in biomedical directions and modifications carried out by doping, surface modification, and thermal annealing toward improving the properties of anodically formed TiO
2
nanotubes. At last, some unsolved issues and possible future directions of this field are indicated.
Pyroptosis is a form of cell death mediated by gasdermin D (GSDMD); it is characterised by NLRP3 inflammasome activation, caspase activation, cell membrane pore formation, and the release of ...interleukin-1β and interleukin-18. NLRP3 inflammasome activation plays a central role in pyroptosis. Recent research has suggested that NLRP3 inflammasome activation may be involved in the occurrence and development of diabetes mellitus and its associated complications. This finding provided the impetus for us to clarify the significance of pyroptosis in diabetes. In this review, we summarise the current understanding of the molecular mechanisms involved in pyroptosis, as well as recent advances in the role of NLRP3 inflammasome activation and pyroptosis in the development of diabetes and diabetic complications.
The activation mechanisms of NLRP3 inflammasome. Display omitted
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