N,N′-Bis(2,6-diisopropyl­phen­yl)-3,6-di­methyl-1,2,4,5-tetra­zine-1,4-dicarboxamide

In the title mol­ecule, C30H42N6O2, the amide-substituted N atoms of the tetra­zine ring deviate from the approximate plane of the four other atoms in the ring by 0.457 (3) and 0.463 (3) Å, forming a boat conformation. The two benzene rings form a dihedral angle of 47.69 (9)°. Intra­molecular N—H⋯N and weak C—H⋯O hydrogen bonds are observed

A reading model of young EFL learners regarding attention, cognitive-load and auditory-assistance

Audio-assisted reading (reading-while-listening) was commonly used as a pedagogical method in English (L2) learning. Numerous studies had reported its efficacy in English (L2) reading. Its efficacy in reading comprehension has been inconclusive due to the lack of studies on the relationship among attention, cognitive load and L2 reading comprehension, with the possibility that the synchronous auditory input lessens attention to the visual input. We present a study of 41 Mandarin-speaking 8-year-old children reading English texts in three modes in a between-participants design. Data of cognitive load, comprehension scores and attention were fitted to a formal mathematical model, which confirmed that influences on L2 reading comprehension could be captured by interactions between attention and cognitive load. Based on the findings, three implications regarding how to appropriately apply auditory-assistant tools to L2 reading were generated

Diaqua­bis[5-(2-pyrid­yl)-1H-tetra­zolato-κ2 N 1,N 5]cobalt(II)

In the title compound, [Co(C6H4N5)2(H2O)2], the Co atom is bonded to two water mol­ecules and two bidentate 5-(2-pyrid­yl)tetra­zolate ligands resulting in a slightly distorted octa­hedral CoN4O2 coordination geometry. The CoII cation is situated on a crystallographic center of inversion. The asymmetric unit therefore comprises one-half of the mol­ecule. The four N atoms belonging to two bidentate 5-(2-pyrid­yl)tetra­zolate ligands lie in the equatorial plane and the two associated water mol­ecules are observed in the axial coordination sites. The crystal structure exhibits a three-dimensional supra­molecular network assembled by inter­molecular O—H⋯N hydrogen bonds

Preparation and evaluation of tamsulosin hydrochloride sustained-release pellets modified by two-layered membrane techniques

AbstractThe aim of the present study was to develop tamsulosin hydrochloride sustained-release pellets using two-layered membrane techniques. Centrifugal granulator and fluidized-bed coater were employed to prepare drug-loaded pellets and to employ two-layered membrane coating respectively. The prepared pellets were evaluated for physicochemical characterization, subjected to differential scanning calorimetry (DSC) and in vitro release of different pH. Different release models and scanning electron microscopy (SEM) were utilized to analyze the release mechanism of Harnual® and home-made pellets. By comparing the dissolution profiles, the ratio and coating weight gain of Eudragit® NE30D and Eudragit® L30D55 which constitute the inside membrane were identified as 18:1 and 10%–11%. The coating amount of outside membrane containing Eudragit® L30D55 was determined to be 0.8%. The similarity factors (f2) of home-made capsule and commercially available product (Harnual®) were above 50 in different dissolution media. DSC studies confirmed that drug and excipients had good compatibility and SEM photographs showed the similarities and differences of coating surface between Harnual® and self-made pellets before and after dissolution. According to Ritger-Peppas model, the two dosage form had different release mechanism

Topically applied tissue factor pathway inhibitor reduced intimal thickness of small arterial autografts in rabbits

AbstractPurpose: The purpose of this study was to investigate whether topically applied tissue factor pathway inhibitor (TFPI) reduces intimal thickness and increases long-term patency of small arterial autografts in rabbits. Methods: An entire 10-mm long section of the left femoral artery was harvested and immersed in saline solution (control group, n = 10), 100 IU/mL of heparin (heparin group, n = 15), or 40 μg/mL of TFPI (TFPI group, n = 15) for 15 minutes. Then the graft was interposed to the right femoral artery. Patency rates were determined by flow measurements throughout the time course of the study, and the grafts were analyzed for measurement of intimal thickness at 3 months after operation. Immunohistochemical analysis was performed to examine whether topically applied TFPI binds to endothelial cells of the grafts. Results: Three-month postoperative patency rates were 10% in the control group, 47% in the heparin group, and 73% in the TFPI group. The TFPI group had a significantly higher patency rate than that of the control group (P <.005). Compared with the heparin group, the TFPI group had a significant reduction in intimal area (0.19 ± 0.05 mm2 vs 0.30 ± 0.09 mm2, P =.0051), in percentage of stenosis (35.7% ± 7.7% vs 61.4% ± 15.8%, P <.0001), and in intimal/media areas ratio (0.64 ± 0.24 vs 1.04 ± 0.33, P =.0051). Immunohistologic analyses confirmed that topically applied TFPI bound to endothelial cells. Conclusion: These results indicate that topically applied TFPI reduces intimal thickness and increases long-term patency of small arterial autografts in rabbits. (J Vasc Surg 2001;34:151-5.

4-(4-Nitro­benz­yl)morpholine

In the title compound, C11H14N2O3, an inter­molecular inter­action between a nitro group O atom and a neighboring benzene ring helps to stabilize the crystal structure [N⋯centroid = 3.933 (2) Å]. No classical hydrogen bonds are observed in the crystal packing