Pulcherrins D-R, potential anti-inflammatory diterpenoids from the roots of Caesalpinia pulcherrima

Bioactivity-guided isolation and purification of the dichloromethane extract from the roots of Caesalpinia pulcherrima yielded 15 new cassane-type diterpenes, named pulcherrins D-R (1-15) together with eight known compounds. The structures of the new metabolites were determined on the basis of spectroscopic analyses including 1D- and 2D-NMR and mass spectroscopy. The anti-inflammatory activity of isolated compounds was investigated with the lipopolysaccharide (LPS)-induced murine macrophage RAW 264.7 cell lines. Compounds 8, 9, 11-15, and 17-23 showed potent NO inhibitory activity.     

Highly sensitive determination of cadmium and lead using a low-cost electrochemical flow-through cell based on a carbon paste electrode

A low-cost thin-layer electrochemical flow-through cell based on a carbon paste electrode (CPE), was constructed for the highly sensitive determination of cadmium(II) (Cd(2+)) and lead(II) (Pb(2+)) ions. The sensitivity of the proposed cell for Cd(2+) and Pb(2+) ion detection was improved by using the smallest channel height without the need for any complicated electrode modification. Under the optimum conditions, the detection limits of Cd(2+) and Pb(2+) ions (0.08 and 0.07 μg dm(-3), respectively) were 13.8- and 11.4-fold lower than that of a commercial flow cell (1.1 and 0.8 μg dm(-3), respectively). Moreover, the percentage recoveries of Cd(2+) and Pb(2+) for the in-house designed thin-layer flow cell were higher than those for the commercially available cell in all tested water samples, and within the acceptable range. The proposed flow cell is promising as an inexpensive and alternative one for the highly sensitive monitoring of heavy metal ions.     

Substituted pyridine coordinated N,N-trans and N,N-cis cyclopalladated complexes of (S)-4-tert-butyl-2-phenyl-2-oxazoline: Crystal structures, spectral study and catalysis of the decomposition of PS pesticides

Three pyridine coordinated cyclopalladated complexes: (S)-chloro{2-[2-(4-tert-butyl)oxazolinyl]phenyl-C,N}(4-R-pyridine)palladium(II) (R = H, 2; R = CF₃, 3; R = NMe₂, 4), have been synthesized and structurally characterized. While the crystal structure shows that 2 has a normal N,N-trans-conformation in the coordination sphere of palladium(II), 3 and 4 exhibit uncommon N,N-cis-conformations. From ¹H NMR measurements, the major coordination isomer in deuterated chloroform solution is N,N-trans configuration for three palladacycles. It was found that the three complexes catalyze effectively the methanolysis of the PS pesticides including chiral thiophosphates but show different activity depending on the substituents of co-coordinated pyridine ring in 2–4.     

Fluorescence sensing of theobromine by simple 2,6-diamino-pyridine and the novel cyclic chair-like hydrogen-bonded tetramer of its diacetyl derivative

2,6-Diaminopyridine is found to be a simple fluorescent sensor for theobromine and its diacetyl derivative 2 also effectively binds theobromine. The receptor-binding sites are based on the co-operative hydrogen-bonding abilities of secondary amides. An unprecedented hydrogen-bonded self-organised cyclic tetrameric supramolecular network is shown for one such small molecule 2 containing one heterocyclic ring in contrast to the binuclear substrates like guanine or pterin which usually form cyclic tetrameric structures.     

Comparison of Fracture Load of the Four Translucent Zirconia Crowns

Recently, translucent zirconia has become the most prevalent material used as a restorative material. This study aimed to compare the crown fracture load of the four most common different translucent zirconia brands available in the market at 1.5 mm thickness. Standardized tooth preparations for a full ceramic crown were designed digitally with software (AutoCAD) by placing a 1.0 mm chamfer margin and 1.5 mm occluso-cervical curvature for the crown sample manufacturing. Stylized crowns were chosen to control the thickness of the crown. The axial and occlusal thickness were standardized to 1.5 mm thickness except at the central pit, which was 1.3 mm thick. The STL file for the tooth dies was prepared using software (3Shape TRIOS^® Patient Monitoring, Copenhagen, Denmark). The tooth dies were printed with a resin material (NextDent Model 2.0, Vertex-Dental B.V., Soesterberg, The Netherlands) using a 3D printing software (3D Sprint^® Client Version 3.0.0.2494) from a 3D printer (NextDent™ 5100, Vertex-Dental B.V., Soesterberg, The Netherlands). The printing layer thickness was 50 µm. Then, a total of twenty-eight (N = 28) stylized crowns were milled out of AmannGirrbach (Amann Girrbach GmbH, Pforzheim, Germany) (n = 7), Cercon HT (Dentsply Sirona, Bensheim, Germany) (n = 7), Cercon XT (Dentsply Sirona, Bensheim, Germany) (n = 7), and Vita YZ XT (Zahnfabrik, Bäd Sackingen, Germany) (n = 7). Following sintering the crowns, sandblasting was performed and they were bonded to the tooth dies with the resin cement (RelyX U-200, 3M ESPE, Seefeld, Germany) and permitted to self-cure under finger pressure for 6 min. The crowns were loaded on the occlusal surface in a universal testing machine (MTS Centurion) with a stainless-steel ball indenter (7 mm radius) with a loading rate of 1 mm/min to contact the stylized crowns on each of the four cusps until failure. A rubber sheet (1.5 mm thickness) was positioned between the crown and indenter, which helped with the load distribution. Statistical analysis was done using SPSS version 20 (IBM Company, Chicago, USA). The fracture loads were analyzed using Dunnett’s T3 test, and the number of cracks was analyzed using the Mann–Whitney U test among the groups. The significant level was set at p value = 0.05. The mean fracture loads were 3086.54 ± 441.74 N, 4804.94 ± 70.12 N, 3317.76 ± 199.80 N, and 2921.87 ± 349.67 N for AmannGirrbac, Cercon HT, Cercon XT, and Vita YZ XT, respectively. The mean fracture loads for the surfaces with the greatest number of cracks (excluding the occlusal surfaces) were on the lingual surface for AmannGirrbach and Cercon HT, on the distal and mesial for Cercon XT, and on the buccal for Vita YZ XT. We found that the AmannGirrbach had the most overall cracks. Cercon XT had the greatest number of occlusal cracks and appeared to be the most shattered. Cercon HT had the least number of cracks. In conclusion, Cercon HT presented the best strength properties, the highest fracture load, and no visible cracks. AmannGirrbach presented the lowest strength properties.     

Effect of Blending Factors on Eri Silk and Cotton Blended Yarn and Fabric Characteristics

Eri cocoons were prepared into short fibers and subsequently blended with cotton fiber in order to develop the new fiber blended yarn in the short spinning system. The Eri and cotton fibers were blended using the drawframe blending with varying blending factors, viz. blending composition (0–100%) and yarn counts (30 and 50 tex). The results showed that Eri fiber which was longer and stronger than cotton fiber, affected the fiber distribution in the yarn cross-section. The mechanical properties of the blended fibers and yarns increased with increasing silk content. Longer fibers of Eri silk tended to move towards the yarn core, especially at silk content higher than 50%. Moreover, stronger and more extensible Eri silk fiber gave an advantage to the improvement of mechanical properties of those blended yarns with silk content higher than 50%. However, with increasing silk content, the blended yarns were more irregular as shown in %CV. Concerning the yarn count effect, the higher yarn count of 50 tex resulted in a more regular yarn with higher yarn strength than that of 30 tex. The plain-woven fabrics were prepared using the blended yarns as a weft yarn and the cotton yarn or silk yarn as a warp yarn. The mechanical properties of those woven fabrics were characterized in order to study the influence of silk contents. The results showed that tensile strength, %elongation and tear strength of woven fabrics using the blended yarn were increased with an increase in silk content. This is an advantage of Eri silk in the aspect of rendering the strength to the blended yarns and fabrics.     

Bis(O,O′-diiso­propyl di­thio­phosphato-S,S′)(1,10-phenanthroline-N,N′)metal(II) complexes with cadmium(II) and iron(II)

The two title compounds, [M(C₆H₁₄O₂PS₂)₂(C₁₂H₈N₂)], where M = Cd^II and Fe^II, are isomorphous. Each compound has a crystallographic twofold axis of symmetry through the metal atom and the 1,10-phenanthroline mol­ecule. The central metal atom is coordinated to four S atoms from the two dithiophos­phate groups and two N atoms from the 1,10-phenanthroline ligand. The environment of the metal atom is a distorted octahedron.     

Dynamically adaptive tree grid modeling for simulation and visualization of rainwater overland flow

Modeling and visualization of a rainwater overland flow is an important tool for a risk assessment, preparation, evacuation planning, and real‐time forecasting of flood warning. The objective of this research is to develop a numerical software to visualize the rainwater overland flow based on a finite volume method for shallow water equations and in combination with the dynamically adaptive tree grid technique and the dynamic domain‐defining method. The obtained simulations for several experiments were tested and compared with results in literature, both theoretical and experimental results. The comparisons with non‐adaptive grids show that the developed algorithm for simulation is very efficient and has a potential for practical usages, in terms of computational times and accuracy. Copyright © 2015 John Wiley & Sons, Ltd.     

Bis[1‐(pyridin‐2‐yl)­ethano­ne‐κN 4‐phenyl­thio­semicarbazonato‐κ2N4,S]­manganese(II)

One half of the mol­ecule of the title complex, [Mn(C₁₄H₁₃N₄S)₂], is related to the other half by a twofold axis passing through the Mn atom. This high‐spin Mn atom is six‐coordinated, in an octahedral geometry, by the azomethine N, the pyridyl N and the thiol­ate S atom of two planar 1‐­(pyridin‐2‐yl)­ethanone N(4)‐phenyl­thio­semicarbazone lig­ands. In the crystal, the mol­ecules are interconnected by N—­H?S and C—H?N interactions, forming a three‐dimensional network.     

11‐Methyl‐12a‐phenyl‐9a,12a‐dihydrophenanthro[9′,10′:5,6][1,4]dioxino[2,3‐d]oxazole and 9a‐(10‐hydroxyphenanthren‐9‐yl)‐11,12a‐diphenyl‐9a,12a‐dihydrophenanthro[9′,10′:5,6][1,4]dioxino[2,3‐d]oxazole

In the title compounds, C₂₄H₁₇NO₃, (I), and C₄₃H₂₇NO₅, (II), the dioxine ring is not planar and tends toward a boat conformation. The oxazoline ring adopts a twisted conformation in mol­ecule (I) but is essentially planar in mol­ecule (II). The configuration of the dioxine–oxazoline system is determined by the sp³ state of the two shared atoms. The phenanthrene moiety is nearly coplanar with the dioxine ring, while the phenyl ring is perpendicular to the attached oxazole ring. The triclinic unit cell of (II) contains two crystallographically independent mol­ecules related by a pseudo‐inversion centre.