Multispectral imaging through metasurface with quasi-bound states in the continuum.

By controlling light fields in subwavelength scales, metasurfaces enable novel ways for miniaturization and integration of spectral imaging system. Metasurfaces supporting quasi bound states in the continuum (quasi-BICs) can control the quality factor and spectral response by changing structural parameters. In this work, we present an ultra-compact multispectral imaging device, whereby spectral modulation is achieved by meta-atoms arrays supporting quasi-BICs.

Meta-Attention Network Based Spectral Reconstruction with Snapshot Near-Infrared Metasurface.

Near-infrared (NIR) spectral information is important for detecting and analyzing material compositions. However, snapshot NIR spectral imaging systems still pose significant challenges owing to the lack of high-performance NIR filters and bulky setups, preventing effective encoding and integration with mobile devices. This study introduces a snapshot spectral imaging system that employs a compact NIR metasurface featuring 25 distinct C symmetry structures.

Effects of Eggshell Thickness, Calcium Content, and Number of Pores in Erosion Craters on Hatching Rate of Chinese Alligator Eggs.

The Chinese alligator (), found only in a small region in southeastern Anhui Province, is listed as critically endangered (CR) by the International Union for Conservation of Nature (IUCN) due to its current declining population trend. Any abnormalities in the physical properties of an egg can decrease the hatching rate. In particular, eggshells play an essential role in embryo development, motivating us to analyze the microstructures of the eggshells of Chinese alligators.

Enhancing Mechanical Properties of 3D Printing Metallic Lattice Structure Inspired by Bambusa Emeiensis.

Metallic additive manufacturing process parameters, such as inclination angle and minimum radius, impose constraints on the printable lattice cell configurations in complex components. As a result, their mechanical properties are usually lower than their design values. Meanwhile, due to unavoidable process constraints (e.

Targeted Singlet Oxygen Delivery: A Bioorthogonal Metabolic Shunt Linking Hypoxia to Fast Singlet Oxygen Release.

Singlet oxygen can be generated by thermal cycloreversion of aromatic endoperoxides. However, for any practical potential of chemically generated singlet oxygen within a therapeutic context, the time and place of the release of this cytotoxic species must be tightly regulated. We now show that using a bimodular design with a hypoxia responsive unit and fluoride-triggered endoperoxide unit, a bioorthogonal metabolic shunt can be established, where an enzymatically generated submicromolar fluoride signal plays a crucial role.

Taming of Singlet Oxygen: Towards Artificial Oxygen Carriers Based on 1,4-Dialkylnaphthalenes.

Naphthalene endoperoxides are known as convenient sources of singlet oxygen (O , Δ ), which is the major product of endoperoxide cycloreversion reaction. However, their potential as carriers of ground-state molecular oxygen (O , Σ ) similar to artificial oxygen carriers remains largely unexplored. This is due to the extreme reactivity and cytotoxic effects of the released singlet oxygen.

Degradation of amyloid peptide aggregates by targeted singlet oxygen delivery from a benzothiazole functionalized naphthalene endoperoxide.

Aggregate structures formed by amyloid-β (Aβ) are correlated with the progression of pathogenesis in Alzheimer's disease. Previous works have shown that photodynamic photosensitizers were effective in oxidatively degrading amyloid-β aggregates and thus decreasing their cytotoxicity under various conditions. In this work, we designed and synthesized a benzothiazole-naphthalene conjugate, with high level of structural analogy to Thioflavin T which is known to have high affinities for the amyloid peptide aggregates.

Distractor-distractor interactions in visual search for oriented targets explain the increased difficulty observed in nonlinearly separable conditions.

The linear separability effect refers to a benefit in search performance observed in a feature-search task, where target and distractor features vary along a continuous feature dimension: Search performance is best when there is a boundary in feature space that separates the distractor features from the target feature. However, the role that distractor heterogeneity plays in this effect is not well understood. Here, we reexamined this effect in the context of a new predictive procedure from Lleras et al.

Total synthesis and biological evaluation of 7-hydroxyneolamellarin A as hypoxia-inducible factor-1α inhibitor for cancer therapy.

7-Hydroxyneolamellarin A (7-OH-Neo A, 1), a natural marine product derived from sponge Dendrilla nigra, was first synthesized with 10% overall yield under the instruction of convergent synthetic strategy. We found that 7-OH-Neo A could attenuate the accumulation of hypoxia-inducible factor-1α (HIF-1α) protein and inhibit vascular epidermal growth factor (VEGF) transcriptional activity, showing well inhibitory effect on HIF-1 signaling pathway. Meantime, 7-OH-Neo A had the well anti-tumor activities, such as inhibiting tumor angiogenesis, proliferation, migration and invasion.

Synthesis and evaluation of 3-(phenylethynyl)-1,1'-biphenyl-2-carboxylate derivatives as new HIF-1 inhibitors.

Selaginellins are a type of rare natural products from the genus Selaginella with unusual alkynyl phenol skeletons and extensive biological activities. Previous structural simplification of these natural compounds afforded a series of diaryl acetylene derivatives with hypoxia-inducible factor 1 (HIF-1) inhibitory activity. In this study, we synthesized thirty compounds by stepwise optimization using methyl 3-(4-methoxylphenyl ethynyl)-[4'-methoxyl-1,1'-biphenyl]-2-carboxylate (1a) as a lead compound and evaluated their HIF-1 inhibitory activity by dual luciferase reporter assay.

Computational study on new natural compound inhibitors of indoleamine 2,3-dioxygenase 1.

Indoleamine 2,3-Dioxygenase (IDO), is a speed limiting enzyme that catalyzes the decomposition and metabolism of Tryptophan along Tryptophan-IDO-Kynurenine pathway [1]. Tryptophan is a necessary amino acid for activating cell growth and metabolism. Additionally, the insufficiency of Tryptophan can lead to immune system dysfunction.

Unimolecular Photodynamic O-Economizer To Overcome Hypoxia Resistance in Phototherapeutics.

Tumor hypoxia has proven to be the major bottleneck of photodynamic therapy (PDT) to clinical transformation. Different from traditional O delivery approaches, here we describe an innovative binary photodynamic O-economizer (PDOE) tactic to reverse hypoxia-driven resistance by designing a superoxide radical (O) generator targeting mitochondria respiration, termed SORgenTAM. This PDOE system is able to block intracellular O consumption and down-regulate HIF-1α expression, which successfully rescues cancer cells from becoming hypoxic and relieves the intrinsic hypoxia burden of tumors in vivo, thereby sparing sufficient endogenous O for the PDT process.

Structure-activity relationships study of neolamellarin A and its analogues as hypoxia inducible factor-1 (HIF-1) inhibitors.

The novel marine pyrrole alkaloid neolamellarin A derived from sponge has been shown to inhibit hypoxia-induced HIF-1 activity. In this work, we designed and synthesized neolamellarin A and its series of derivatives by a convergent synthetic strategy. The HIF-1 inhibitory activity and cytotoxicity of these compounds were evaluated in Hela cells by dual-luciferase reporter gene assay and MTT assay, respectively.

OsASR5 enhances drought tolerance through a stomatal closure pathway associated with ABA and H O signalling in rice.

Drought is one of the major abiotic stresses that directly implicate plant growth and crop productivity. Although many genes in response to drought stress have been identified, genetic improvement to drought resistance especially in food crops is showing relatively slow progress worldwide. Here, we reported the isolation of abscisic acid, stress and ripening (ASR) genes from upland rice variety, IRAT109 (Oryza sativa L.

Hydrazine-promoted sequential cation exchange: a novel synthesis method for doped ternary semiconductor nanocrystals with tunable emission.

Using ZnSe nanocrystals (NCs) as starting material, Ag-doped or Cu-doped ZnCdSe ternary NCs were prepared by hydrazine-promoted sequential cation exchange in aqueous media. The composition of the NCs can be flexibly controlled by varying the amount of intermediate Ag or Cu cation addition, thus changing the emission of the ternary NCs while preserving the NC size. According to Vegard's law, the as-prepared ternary NCs possess an alloyed structure.