4-(2,5-Dihexyl­oxyphen­yl)benzoic acid

In the title compound, C25H34O4, one n-hexyl chain of the hex­yloxy group adopts a fully extended all-trans conformation, and the other n-hexyl chain displays disorder with site occupancies of 0.470 (3) and 0.530 (3). The dihedral angle between the benzene rings is 44.5 (3)°. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds form dimers via crystallographic inversion centres

4,4′-(Anthracene-9,10-di­yl)dibenzoic acid dimethyl­formamide disolvate

In the title compound, C28H18O4·2C3H7NO, the dihedral angle between the benzene rings and the anthracene system is 74.05 (12)°. A crystallographic inversion centre is located in the middle of the anthracene unit. The dimethyl­formamide solvent mol­ecules are partially disordered over two positions of approximately equal occupancy [0.529 (6):0.471 (6)]. Inter­molecular O—H⋯O hydrogen bonds with the major occupancy formamide O atom as acceptor result in the formation of 2:1 solvate–complex aggregates, which are alternately linked to shorter solvate units via weak inter­molecular C—H⋯O contacts generated from the rotational disorder of the formamide O atom (minor occupancy component). Weak C—H⋯π inter­actions between the solvent mol­ecules as the donor and the outer anthracene rings support these contacts in the crystal structure for both disorder components

Lattice and QR decomposition-based algorithms for recursive least squares adaptive nonlinear filters

Journal ArticleThis paper presents a lattice structure for adaptive Volterra systems. The stucture is applicable to arbitrary planes of support of the Volterra kernels. A fast least squares lattice and a fast QR-lattice adaptive nonlinear filtering algorithms based on the lattice structure are also presented. These algorithms share the fast convergence property of fast least squares transversal Volterra filters; however, unlike the transversal filters they do not suffer from numerical instability

Aqueous Synthesis of ZnSe/ZnS-2-R-Benzothiazole Nanocrystals with White Emission

We prepared water-soluble white light-emitting ZnSe/ZnS-2-R-benzothiazole nanocrystals (NCs), R = 2-hydroxy-5-(2,5-dimethyl-thienyl)-phenyl. The penicillamine (Pen) capped ZnSe/ZnS NCs were firstly prepared with high photoluminescence quantum yields (PL QY) of 40%. Then they bond to 2-R-benzothiazole molecules, resulting in white light-emitting ZnSe/ZnS-2-R-benzothiazole NCs with QY of 75% over a 375 to 650 nm range of emission, which can be applied to white light-emitting diodes. The ZnSe/ZnS-2-R-benzothiazole NCs with two emission bands at around 451 and 557 nm were discussed and the possible mechanism of the interaction of ZnSe/ZnS NCs with 2-R-benzothiazole was also proposed

Alterations in amino acid levels and metabolite ratio of spinal cord in rat with myocardial ischemia-reperfusion injury by proton magnetic resonance spectroscopy

Abstract Objectives The mechanism behind spinal metabolites and myocardial ischemia-reperfusion (IR) injury is not well understood. Proton magnetic resonance spectroscopic analysis of spinal cord extracts provides a quick evaluation of the specific metabolic activity in rats with myocardial IR injury. We investigated the relationship between the IR-related variables and the changes in spinal metabolites. Methods Proton magnetic resonance spectroscopy (1H-MRS) was used to assess the spinal metabolites of adult rats with and without myocardial IR injury (n=6 per group). Myocardial IR injury was reproduced using intermittent occlusion of the left anterior descending coronary artery. We studied the relationship between the metabolite ratio measurement and IR-related variables. All rats underwent 1H-MRS, with the ratio of interest placed in different spinal cord segments to measure levels of twelve metabolites including N-acetylaspartate (NAA), taurine (Tau),glutamate (Glu),gamma amino acid butyric acid (GABA),creatine (Cr), and myoinositol (MI), etc. Results Rats with myocardial IR injury had higher concentration of Tau in the upper thoracic spinal cord (p< 0.05), and lower concentration of Gly and Glu in the cervical segment of the spinal cord (p< 0.05), when compared to the Control group. The ratios of glutamate/taurine (Glu/Tau), Glu/(GABA+Tau) and Glu/Total were significantly different between the IR group and the Control group in the upper thoracic spinal cord (p< 0.05). So were the ratios of Glu/(GABA+Tau) in the cervical segment (p< 0.05),and Glu/Tau and Glu/(GABA+Tau) in the lower thoracic spinal cord (p< 0.05). Conclusions These findings suggest that myocardial IR injury may be related to spinal biochemical alterations. It is speculated that these observed changes in the levels of spinal metabolites may be involved in the pathogenesis and regulation of myocardial IR injury. Keywords: myocardial ischemia-reperfusion injury; spinal cord; metabolomics; proton nuclear magnetic resonanc

Self-aggregated nanoparticles of N-dodecyl,N′-glycidyl(chitosan) as pH-responsive drug delivery systems for quercetin

In this study, pH-responsive amphiphilic chitosan (CS) nanoparticles were used to encapsulate quercetin (QCT) for sustained release in cancer therapy. The novel CS derivatives were obtained by synthesis with 2,3-epoxy-1-propanol, also known as glycidol, followed by acylation with dodecyl aldehyde. Characterization was performed by spectroscopic, viscosimetric, and size-determination methods. Critical aggregation concentration, morphology, entrapment efficiency, drug release profile, cytotoxicity, and hemocompatibility studies were also carried out. The average size distribution of the self-assembling nanoparticles measured by dynamic light scattering ranged from 140 to 300 nm. In vitro QCT release and Korsmeyer–Peppas model indicated that pH had a major role in drug release. Cytotoxicity assessments indicated that the nanoparticles were non-cytotoxic. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay further revealed that QCT-loaded nanoparticles could inhibit MCF-7 cell growth. In vitro erythrocyte-induced hemolysis indicated the good hemocompatibility of the nanoparticles. These results suggest that the synthesized copolymers might be potential carriers for hydrophobic drugs in cancer therapy

Aggregation-Induced Emission (AIE), Life and Health

Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health