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Due to their unique semiconducting properties, conjugated porous organic polymers (CPOPs) have garnered significant interest in various photocatalysis applications. In this study, we synthesize three thiazolo[5,4‐d]thiazole (TzTz)‐linked CPOPs with three polyaryl rigid cores of benzene (CPOP1), pyrene (CPOP2), and triazine (CPOP3). We investigated their efficacy in catalyzing visible light‐driven C−N bond formation reactions, including C−N cross‐couplings between aryl bromides and amines and amination reactions from aryl bromides and sodium azides. Among the three, only CPOP2, combined with NiCl2 or Ni(dtbbpy)Cl2, effectively facilitated these transformations. Notably, CPOP2 exhibited photocatalytic activities approximately six times higher than its small molecular counterpart C1 in both reactions. The CPOP catalyst was easily recovered through centrifugal separation and reused for five catalytic cycles with minimal loss of activity. Theoretical calculations revealed that the deliberate structural design of polyaryl moieties could effectively tune the energy gap, which is crucial for the photocatalytic activity in organic reactions. This study, therefore, demonstrates a novel application of TzTz‐linked CPOPs for heterogeneous photocatalytic organic transformations. [ABSTRACT FROM AUTHOR]

Conductive hydrogels, characterized by their unique features of flexibility, biocompatibility, electrical conductivity, and responsiveness to environmental stimuli, have emerged as promising materials for sensitive strain sensors. In this study, a facile strategy to prepare highly conductive hydrogels is reported. Through rational structural and synthetic design, silver nanowires (AgNWs) are incorporated into poly(N‐acryloyl glycinamide) (PNAGA) hydrogels, achieving high electrical conductivity (up to 0.88 S m−1), significantly enhanced mechanical properties, and elevated deformative sensitivity. Furthermore, surface modification with polyhexafluoropropylene oxide (PHFPO) has substantially improved the water retention capacity and dressing comfort of this hydrogel material. Based on the above merits, these hydrogels are employed to fabricate highly sensitive wearable strain sensors which can detect and interpret subtle hand and finger movements and enable precise control of machine interfaces. The AgNWs/PNAGA based strain sensors can effectively sense finger motion, enabling the control of robotic fingers to replicate the human hand's gestures. In addition, the high deformative sensitivity and elevated water retention performance of the hydrogels makes them suitable for flow sensing. These conceptual applications demonstrate the potential of this conductive hydrogel in high‐performance strain sensors in the future. [ABSTRACT FROM AUTHOR]

Recent interest has surged in using heterogeneous carriers to boost synergistic photocatalysis for organic transformations. Heterogeneous catalysts not only facilitate synergistic enhancement of distinct catalytic centers compared to their homogeneous counterparts, but also allow for the easy recovery and reuse of catalysts. This mini‐review summarizes recent advancements in developing heterogeneous carriers, including metal–organic frameworks, covalent–organic frameworks, porous organic polymers, and others, for synergistic catalytic reactions. The advantages of porous materials in heterogeneous catalysis originate from their ability to provide a high surface area, facilitate enhanced mass transport, offer a tunable chemical structure, ensure the stability of active species, and enable easy recovery and reuse of catalysts. Both photosensitizers and catalysts can be intricately incorporated into suitable porous carriers to create heterogeneous dual photocatalysts for organic transformations. Notably, experimental evidence from reported cases has shown that the catalytic efficacy of heterogeneous catalysts often surpasses that of their homogeneous analogues. This enhanced performance is attributed to the proximity and confinement effects provided by the porous nature of the carriers. It is expected that porous carriers will provide a versatile platform for integrating diverse catalysts, thus exhibiting superior performance across a range of organic transformations and appealing prospect for industrial applications. [ABSTRACT FROM AUTHOR]

An unprecedented DMAP-catalysed amidation of aryl and alkyl carboxylic acids with organo-cyanamides has been developed. Unlike the use of N-cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS) as an electrophilic cyanating reagent, an unusual desulfonylation/decyanation reaction model has been disclosed for the first time. Remarkable features of this reaction include readily available substrates, simple operation and broad scope, enabling the efficient synthesis of structurally diverse amides. The synthetic utility of this protocol was demonstrated by the late-stage amidation of bioactive carboxylic acids and a scale-up reaction. [ABSTRACT FROM AUTHOR]

The chemical corrosion aging of plutonium is a very important topic. It is easy to be corroded and produces oxidation products of various valence states because of its 5f electron orbit between local and non-local. On the one hand, the phase diagram of plutonium and oxygen is complex, so there is still not enough research on typical structural phases. On the other hand, most of the studies on plutonium oxide focus on PuO2 and Pu2O3 with stoichiometric ratio, while the understanding of non-stoichiometric ratio, especially for Pu2O3-x, is not deep enough. Based on this, using the DFT + U theoretical scheme of density functional theory, we have systematically studied the structural stability, lattice parameters, electronic structure, mechanical and optical properties of six typical high temperature phases of β -Pu2O3, α -Pu2O3, γ -Pu2O3, PuO, α -PuO2, γ -PuO2. Further, the mechanical properties and optical behavior of Pu2O3-x under different oxygen vacancy concentrations are analyzed and discussed in detail. The result shows that the elasticity modulus of single crystal in mechanical properties is directly related to the oxygen/plutonium ratio and crystal system. As the number of oxygen vacancies increases, the mechanical constants continue to increase. In terms of optical properties, PuO has the best optical properties, and the light absorption rate decreases with the increase of oxygen vacancy concentration. [ABSTRACT FROM AUTHOR]

Herein, we report a DMAP-catalysed Curtius rearrangement and intramolecular cyclisation cascade reaction of 2-substituted aryl carboxylic acids with organic azides for the first time. This protocol features simple operation, broad scope and metal-free conditions, furnishing a broad spectrum of biologically attractive heterocycles. The synthetic virtue of this reaction was demonstrated by gram-scale synthesis and applicability toward drug-like molecules. [ABSTRACT FROM AUTHOR]

An unprecedented deoxygenative gem-difluorovinylation of aliphatic alcohols using α-trifluoromethyl alkenes is achieved under photocatalytic conditions. Inexpensive Ph3P acts as an efficient O-atom transfer reagent to facilitate the deoxygenation of alcohols for the generation of reactive alkyl radical species. Remarkable features of this reaction include mild conditions, simple operation and broad scope. The synthetic utility of this reaction was validated by the success of two-step one-pot reactions, scale-up synthesis and chemoselective monodeoxygenation of diols. [ABSTRACT FROM AUTHOR]

Introduction: Cerebral ischemia induces reactive proliferation of astrocytes (astrogliosis) and glial scar formation. As a physical and biochemical barrier, the glial scar not only hinders spontaneous axonal regeneration and neuronal repair but also deteriorates the neuroinflammation in the recovery phase of ischemic stroke. Objectives: Previous studies have shown the neuroprotective effects of the valproic acid (2-n-propylpentanoic acid, VPA) against ischemic stroke, but its effects on the ischemia-induced formation of astrogliosis and glial scar are still unknown. As targeting astrogliosis has become a therapeutic strategy for ischemic stroke, this study was designed to determine whether VPA can inhibit the ischemic stroke-induced glial scar formation and to explore its molecular mechanisms. Methods: Glial scar formation was induced by an ischemia-reperfusion (I/R) model in vivo and an oxygen and glucose deprivation (OGD)-reoxygenation (OGD/Re) model in vitro. Animals were treated with an intraperitoneal injection of VPA (250 mg/kg/day) for 28 days, and the ischemic stroke-related behaviors were assessed. Results: Four weeks of VPA treatment could markedly reduce the brain atrophy volume and improve the behavioral deficits in rats' I/R injury model. The results showed that VPA administrated upon reperfusion or 1 day post-reperfusion could also decrease the expression of the glial scar makers such as glial fibrillary acidic protein, neurocan, and phosphacan in the peri-infarct region after I/R. Consistent with the in vivo data, VPA treatment showed a protective effect against OGD/Re-induced astrocytic cell death in the in vitro model and also decreased the expression of GFAP, neurocan, and phosphacan. Further studies revealed that VPA significantly upregulated the expression of acetylated histone 3, acetylated histone 4, and heat-shock protein 70.1B in the OGD/Re-induced glial scar formation model. Conclusion: VPA produces neuroprotective effects and inhibits the glial scar formation during the recovery period of ischemic stroke via inhibition of histone deacetylase and induction of Hsp70.1B. [ABSTRACT FROM AUTHOR]

Inducing new nonlinear optical (NLO) properties while maintaining the thermal stability of carbon based nanomaterials broadens the application of carbon nanomaterials in opto-electronics. In the present work, polar azulene defects are introduced in Y-type carbon based molecules to induce polarity thus enhancing the second order NLO properties (for example, the static first hyperpolarizability of Y-type carbon based molecules with azulene defects reaches 4.18 × 10−30 esu per heavy atom while that of p-nitroaniline is 2.97 × 10−30 esu per heavy atom). The addition of an electron acceptor at the heptagon end modifies the π electron distribution of Y-type carbon based molecules and significantly enhances the static first hyperpolarizability from 1.73 × 10−30 esu per heavy atom to 8.87 × 10−30 esu per heavy atom, much larger than that of similarly synthesized NLO compounds. The cause of such enhancement by introduction of electron acceptors has been scrutinized. [ABSTRACT FROM AUTHOR]

Byline: Hong-bin Deng, Yuan-yuan He, Zhen-yong Guo In this paper, a fast detection method of moving target from real-time airborne videos is presented. We first explore the motion relationship in an airborne video and utilise the global motion estimation to estimate the background movement, and then use binocular interpolation for motion compensation; thus, the moving target detection in dynamic airborne videos is converted into detection in static backgrounds. A method involving the multiplication of the differences of the symmetrical images among three adjacent frames is adopted to enhance moving target and increase the difference between the target and background noises. The regional growth and morphological image processing techniques are employed finally to realise target segmentation. Experimental results demonstrate the effectiveness and robustness of our algorithm.

This study evaluated transepithelial transport mechanisms of Ile‐Gln‐Pro (IQP) and Val‐Glu‐Pro (VEP), two ACE‐inhibitory peptides derived from Spirulina platensis, using human intestinal Caco‐2 cell monolayers. IQP and VEP were absorbed intact through Caco‐2 cell monolayers with Papp values of 7.48 ± 0.58 × 10−6 and 5.05 ± 0.74 × 10−6 cm/s, respectively. The transport of IQP and VEP were affected neither by Gly‐Pro nor by wortmannin, indicating that they were not PepT1‐mediated and did not involve endocytosis. However, transport of IQP and VEP were increased significantly by sodium deoxycholate, suggesting that the major transport mechanism was paracellular. In addition, the increased transport of VEP and IQP were followed with the addition of sodium azide, suggesting influence of energy to the process. The transport of VEP was also increased by verapamil, indicating an apical‐to‐basolateral flux mediated by P‐gp. Practical Application: Bioactive peptides derived from food proteins have been considered as potentially ideal products to reduce hypertension because of their safety and positive impacts on health. IQP and VEP are the 2 ACE inhibitory peptides derived from Spirulina platensis, a kind of edible cyanobacteria with rich nutrition and multiple physiological functions, and were demonstrated to inhibit ACE and lower blood pressure in spontaneously hypertensive rats. However, it is prerequisite that such bioactive peptides must be absorbed intact across the intestinal epithelium, so as to exert antihypertensive effects in vivo. This study evaluated transepithelial transport mechanisms of IQP and VEP. It contributes to the study of Spirulina in lowering blood pressure and supports the development of bioactive peptide products. [ABSTRACT FROM AUTHOR]

Producing nanoporous carbons that possess high porosity and superior electrochemical performance is a challenge for scientists. In this work, a simple and efficient template carbonization method, without any physical/chemical activation treatment, has been implemented to produce nanoporous carbons doped with nitrogen species. 4-(4-Nitrophenylazo)resorcinol serves as a carbon/nitrogen source and Mg(OH)2as a hard template. All resultant carbon samples are amorphous, highly porous in nature and display sheet-like nanostructures. The carbon-1:3-L sample whose precursor is obtained by solution method exhibits better porosity, and larger nitrogen content, than those obtained by solid state method (the carbon-1:3-S sample). The carbon-1:3-L sample exhibits large specific surface area (SBET) of 1427.7 m2 g-1and high total pore volume (VT) of 5.91 cm3 g-1whereas those of the carbon-1:3-S sample are of 1036.6 m2 g-1 and 4.76 cm3 g-1 respectively. Notably, the present pore volumes are much higher than most of the previously reported for nanoporous carbons. As a consequence, the carbon-1:3-L sample delivers superior electrochemical behaviors, whose specific capacitance reaches up to 378.5 F g-1 when measured at 1 A g-1 in a three-electrode system, compared with that of 263.4 F g-1 of the carbon-1:3-S sample. The present Mg(OH)2-assisted template carbonization method is simple and easy to operate, indicating its potential application for producing nanoporous carbons. [ABSTRACT FROM AUTHOR]

This paper considers the ergodic weighted sum rate maximization (WSRMax) problem for an underlay cognitive radio multiple input single output (MISO) broadcast channel. In this setting, a secondary network, consisting of a base-station with M transmit antennas and K single-antenna secondary users (SUs), is allowed to share the same spectrum with a primary user (PU), under an average total transmit power (ATTP) constraint and an average interference power (AIP) constraint at the PU receiver. We show that the ATTP constraint always remains active, and as the maximum ATTP Pav→ ∞, the ergodic WSR approaches infinity similar to conventional non-CR networks. We propose a novel low-complexity suboptimal beamforming scheme termed "Partially-Projected & Regularized Zero-Forcing Beamforming" (PP-RZFBF) with a close-form beamformer, by combining the regularized zero-forcing (RZF) with the channel projection idea, to achieve a tradeoff between maximizing secondary throughput and suppressing secondary multiuser interference as well as the interference on PU. In order to analyze and optimize the performance of this scheme, we employ the large system analysis technique, in the limit as M and K approach infinity with a fixed ratio r=\frac{K}{M}. This allows us to derive deterministic limiting approximations for the PP-RZFBF problem which enables us to determine asymptotically optimal beamformers for PP-RZFBF. In the large system limit, for the PP-RZFBF scheme, we also find that as Pav→ ∞, the interference on PU caused by the secondary transmission is asymptotically removed. A special suboptimal beamforming scheme called "CZFBF" is also considered, which involves zero forcing all the interference, including the secondary multiuser interference as well as the interference imposed on PU. Various interesting comparisons between PP-RZFBF and CZFBF are provided. Numerical simulations illustrate that the asymptotically optimal beamformers for the PP-RZFBF scheme provide an excellent performance even for finite-sized systems. [ABSTRACT FROM PUBLISHER]

The anti-inflammatory effect of Dan-Lou tablets (DLT) have been reported; however, the signaling pathways involved and their role in foam cell formation remains unclear. The purpose of this study was to determine the molecular target and mechanism of DLT in the treatment of coronary heart disease (CHD), and investigate the role of DLT in inhibiting foam cell formation and the anti-inflammatory effects of RAW 264.7 macrophages. This study explored and elucidated the main active components, therapeutic targets, and pharmacological mechanisms of DLT treatment for CHD using network pharmacology. Secondly, the accuracy of the interaction of key active compounds with key proteins was verified by molecular docking analysis. Eight chemical compositions were determined from the ethanol extract of DLT (EEDL) by high-performance liquid chromatography. Finally, this study used EEDL intervention with oxidized low-density lipoprotein (ox-LDL) to induce RAW264.7 macrophages to verify the results of network pharmacology. According to network pharmacological analysis, 269 common targets of DLT and CHD were obtained from an online database, and 24 key targets were obtained from further analysis. GO enrichment and KEGG analyses were performed, mainly involving the cAMP, cGMP-PKG, MAPK, and NF-κB signaling pathways, and vascular smooth muscle contraction. Molecular docking showed that the active components in DLT docked well with MyD88, NF-κB, and p38 MAPK. The eight compounds from the EEDL have been identified as gallic acid, salvianolic acid, puerarin, daidzein, paeoniflorin, salvianolic acid B, cryptotanshinone, and tanshinone IIA with concentrations of 4.62, 4.76, 23.73, 34.24, 14.59, 21.69, 0.34, and 0.47 μg/mg, respectively. Further in vitro experiments showed that the levels of MyD88 and p-p38 MAPK in RAW 264.7 macrophages induced by ox-LDL increased noticeably. Stimulating the NF-κB signaling pathway increased the release of pro-flammatory factors (TNF-α and IL-1β) and strengthened the inflammatory response (P < 0.05 or P < 0.01), while the levels of MyD88, p38 MAPK, NF-κB, TNF-α, and IL-1β decreased after EEDL treatment (P < 0.05 or P < 0.01). The study demonstrated that the anti-inflammatory activity of the DLT intervention of ox-LDL-induced RAW 264.7 macrophages may involve the MyD88/p38 MAPK/NF-κB signaling pathway. [Display omitted] • In this study, through network pharmacological analysis, molecular docking and in vitro experimental study, the therapeutic effect and mechanism of Dan-Lou tablets on coronary heart disease were discussed. • The study shows that the mechanism of Dan-Lou tablets intervention on coronary heart disease may be related to MyD88/p38 MAPK/NF-κB signal pathway. • This study not only provides a scientific basis for the clinical application of Dan-Lou tablets in the treatment of coronary heart disease, but also provides new enlightenment for the traditional Chinese medicine pharmacological mechanism of Dan-Lou tablets in the treatment of complex diseases. [ABSTRACT FROM AUTHOR]