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A novel [1+1] Schiff-base macrocyclic compound 3 has been synthesized from precursor 1, 1,3-bis(2′-formylphenoxy)-2-propanol, and precursor 2, resorcinol-bis(4-aminophenyl)ether, via condensation and cyclizaction using Ba2+ as template. The macrocycle 3 was further reduced giving saturated macrocycle 4. The structures of 3 and 4 were characterized by elemental analysis, 1H NMR, IR, and MS spectra, and their structures were determined via single crystal X-ray diffraction studies. X-ray diffraction analysis revealed that the macrocyclic compound 3 has a folded conformation, and the corresponding reduced product 4 adopts a twisted and folded conformation due to its flexible nature.

Amorphous Cr–C alloy coating was prepared by electrodepositing. The microhardness of the coating was tested after annealing from 100°C to 800°C and the crystallization evolution was studied by the analysis of X-ray diffraction (XRD) and differential scanning caborimetry (DSC). The results showed that the crystallization evolution of the coating began at 300°C and finished around 450°C, and intermetallic compound Cr7C3and Cr23C6appeared when heat treatment temperature reached around 600°C. The microhardness, corrosion resistance as well as the adhesion of the coating all increased first with the temperature and then dropped until it attained the proper values. The microhardness reached the maximum of 1610HV0.025at 600°C. While the corrosion resistance and the adhesion force attained the peak value at about 400°C.

Five new silver(I) coordination polymers of types [Ag2L1(NO3)2]n (1), [Ag2L2(NO3)2]n (2), [Ag2L3(NO3)2]n (3), [Ag2L4(NO3)2]n (4), and [AgL5(NO3)]n (5) have been synthesized, where L1–L5 are the Schiff base ligands formed from 2:1 condensation of acetylacetone with the symmetrical diamines H2N(CH2)nNH2, with n = 2 and 6 to give L1 and L2, 1,2-bis(2-aminophenoxy)ethane to give L3, 1,4-bis(2-aminophenoxy)butane to give L4, and 1,6-bis(4-aminophenoxy)butane to give L5. The single crystal X-ray structures of the Ag(I) complexes 1–5 have been determined. Both 1 and 2 adopt three-dimensional polymeric network structures, while 3–5 adopt two-dimensional-layered framework structures. In 1 and 2, the terminal O and γ-C atoms of two acacH-imine domains of the same ligand bind to different silver ions, while in each of 3–5 a γ-C from one or both acacH-imine domains binds to a silver ion, with the remaining coordination sites occupied by bridging monodentate or bidentate nitrato groups and/or a Schiff base ligand oxyg...

Sensory gating, a viable function of the brain, is an adaptive mechanism to prevent overstimulation of nervous system. The aim of this study was to examine the effect of homobaric pure (i.e. 100%) oxygen on the human brain at different periods of inhalation. EEG was recorded while an auditory paired-click sensory gating test was conducted during 4 study periods: before inhalation of pure oxygen (Before), inhalation of 100% oxygen (air in control group) for 20 min (Oxy20) and 50 min (Oxy50), 30 min after oxygen (air in control group) inhalation (After). Each of the auditory stimuli elicited 4 clear peaks at 20, 39, 55 and 100 ms in ERPs, demonstrating that sensory gating is a multi-stage process. Comparing the S1-S2 differences of field potentials between two groups, significant experimental effects (P < 0.05-0.01) were shown at Oxy50 and After periods mainly at the 20 and 100 ms peak in ERPs. Pure oxygen was experimentally shown, for the first time, to affect the human brain activation, at the beginning of early P20 sensory cortical activation and late N100 auditory perception. The effect found in this study shall encourage further investigation on the oxygen treatment in human brain.

Sensitization to perennial aeroallergens correlates with the risk of persistent asthma (AS) in children. In tropical Singapore, multiple codominant species of mites abound in the indoor environment, and preferential species-specific sensitization has been associated with different phenotypes of allergic disease. We investigated the pattern of mite component-specific IgE (mcsIgE) in children with different phenotypes of clinical allergic disease in an environment with multiple mite species exposure. A prospective evaluation of newly diagnosed patients with clinical diagnosis of allergic rhinitis (AR), atopic dermatitis (AD), or AS and sensitization to one or more aeroallergens were performed. Sera were tested for specific IgE against an extensive panel of Dermatophagoides pteronyssinus and Blomia tropicalis allergens. A total of 253 children were included, mean age 7.3 yr, 79% fulfilled criteria for AR, 46% AS, 71% AD, and 31% for all three. Sensitization to one or both mites was observed in 91% of children, 89% were sensitized to D. pteronyssinus, and 70% to B. tropicalis. The most common mite allergens recognized by these atopic children were Der p 1 (64%), Der p 2 (71%), Blo t 5 (45%), Blo t 7 (44%), and Blo t 21 (56%). Specific IgE responses to an increased number of distinct mite allergens correlated with the complexity of the allergic phenotype. In multivariate analysis, an increased risk for the multi-systemic phenotype (AR + AS + AD) was associated with sensitization to an increased repertoire of mite components (three or more) (OR 4.3, 95% CI 2.1-8.8, p = 0.001) and a positive parental history of AS (OR 2.4, 95% CI 1.2-2.9, p = 0.013). A highly pleiomorphic IgE response to the prevalent indoor mites is associated with the presence of a multi-systemic allergic phenotype in childhood in a tropical environment.

The 1:1 interaction of the diastereopure Schiff bases (1S,2S)-bis(acetylacetone)-cyclohexanediimine ( L 1 ) and (1R,2R)-bis(acetylacetone)cyclohexanediimine ( L 2 ) with CdI 2 yields the new helical metal coordination polymers [Cd L 1 I 2 ] n ( 1 ) and [Cd L 2 I 2 ] n ( 2 ). The respective X-ray structures, as expected, confirmed 1 and 2 to be enantiomeric, existing as right-handed ( P ) and left-handed ( M ) helical chains in which both L 1 and L 2 are formally present in their (unusual) uncharged ketoamine form, with the (protonated) amine nitrogens not coordinated. The Cd(II) centres in 1 and 2 display distorted tetrahedral coordination geometries being bound to two iodo ligands and two oxygen donor atoms from individual ketoamine domains belonging to different Schiff base ligands.

Square-planar nickel(II) complex with tridentate ONO-donor 4-[(2-hydroxyphenyl)imino]-2-pentanone (H2hpac) and imidazole (Himdz) are reported. The complex was synthesized in moderate yield by reacting Ni(O2CCH3)2 · 4H2O, H2hpac and imidazole in 1 : 1 : 1 mole ratio and characterized by elemental analysis, IR, 1H NMR spectroscopy. An X-ray structure determination of the complex has been completed. In the solid state, a one-dimensional assembly of the [Ni(hpac)(Himdz)] molecules is formed via intermolecular hydrogen bonds between the imidazole N–H groups and the coordinated hydroxyphenyl-O atoms.

Two isomorphic acetylacetone-based complexes, trans-bis(acetylacetone)-1,4cyclohexanediimine (TBAC) and cis-bis(acetylacetone)-1,4-cyclohexanediimine (CBAC), were designed to promote complex formation on reaction with AgX (X = NO3-, ClO4-, BF4-, SbF6- and SO3CF3-) and were employed to generate nine silver coordination polymers (CPs), {[Ag(TBAC)]·2H2O·BF4}n (1), [Ag(TBAC)0.5(NO3)]n (2), [Ag2(TBAC)2(ClO4)2]n (3), [Ag(TBAC)(CF3SO3)(H2O)]n (4), {[Ag(TBAC)2]·SbF6}n (5), {[Ag(CBAC)]·BF4}n (6), {[Ag(CBAC)(H2O)]·ClO4}n (7), {[Ag(CBAC)(H2O)]·CF3SO3}n (8) and {[Ag(CBAC)(H2O)]·SbF6}n (9), that exhibit structural and topological diversity as determined by single-crystal X-ray diffraction analyses. The complexes were further characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD) and thermogravimetric (TG) analyses. Complex 1 exhibited a 3D (4,4)-connected pts topology with the Schläfli symbol of (42·84). The NO3- anions in 2 are μ2-bridging linkers, connecting the 1D [Ag(TBAC)0.5]n chains to 2D (3,4)-connected nets. In 3, TBAC is a tridentate ligand to bind Ag(I) ions to form a 1D ladder-like supramolecular structure. Complex 4 has 2D (3,3)-connected nets where both Ag(I) ions and TBAC ligands are 3-connected nodes. Complex 5 has a 1D fishbone chain structure where some of the TBAC moieties are bidentate. The cis isomer, CBAC, gives similar (3,3)-connected networks where the Ag(I) ions and CBAC ligands are 3-connected nodes in the resultant 6-9. Although the host networks in 6-9 are supramolecular isomers, structural comparisons revealed that use of cis and trans isomers of the ligand and different counterions significantly influence the structures. The luminescent properties of all complexes and ligands were investigated.

[Hg2(L1)2I4] (1), [Cd2(L1)2I4] (2), {[Cd(L1)2(SO4)(H2O)]·4H2O}n (3), {[Zn2(L2)2(Cl)4]·0.5H2O} (4), {[Cu2(L2)2(SO4)2(H2O)4]·2.5H2O} (5) and {[Cd(L2)2(SO4)(H2O)]·3H2O}n (6), based on N–(3–picolyl)–N’–(3–pyridyl)urea (L1) or N–(4–picolyl)–N’–(3–pyridyl)urea (L2), have been synthesized and characterized by elemental analyses (EA), IR spectra, single-crystal and powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Complexes 1 and 2 are isomorphous and feature similar rectangular metal organic loops, which were further extended into 2D supramolecular structures through hydrogen bonds. Complex 3 possesses a 2D sql sheet, and the channels between the neighboring sheets are filled with lattice water molecules, which formed a 1D water tape. Complex 4 also exhibits a rectangular metal organic loop and a 3D supramolecular structure with the help of hydrogen bonding interactions. Complex 5 also possesses a metal organic loop, and the water molecules interacted with sulfates, constructing a 1D water-sulfate tube. Complex 6 features a 1D loop polymeric chain. Moreover, the solid state luminescences of 1-4 and 6 have been investigated.

This paper proposes a new primary lazy update protocol, PTCS (Primary Transaction Commit Schedule). In the PTCS protocol, a serializable primary transaction schedule is generated firstly and then the secondary transactions are committed according to the serializable primary transaction schedule. PTCS protocol can guarantee serializability if the data copy graph contains no directed circles. It can also be extended to eliminate all requirements on the data copy graph. Compared to earlier works, PTCS protocol not only imposes a much weaker requirement on the data placement, but also avoids the deadlock caused by transaction waits and extra message overhead. The performance experiments show that the degradation of the performance caused by the replica management of the PTCS protocol is tolerable.

The puzzling properties of quantum mechanics, wave-particle duality, entanglement and superposition, were dissected experimentally at past decades. However, hidden-variable (HV) models, based on three classical assumptions of wave-particle objectivity, determinism and independence, strive to explain or even defeat them. The development of quantum technologies enabled us to test experimentally the predictions of quantum mechanics and HV theories. Here, we report an experimental demonstration of an entanglement-assisted quantum delayed-choice scheme using a liquid nuclear magnetic resonance quantum information processor. This scheme we realized is based on the recently proposed scheme [Nat. Comms. 5:4997(2014)], which gave different results for quantum mechanics and HV theories. In our experiments, the intensities and the visibilities of the interference are in consistent the theoretical prediction of quantum mechanics. The results imply that a contradiction is appearing when all three assumptions of HV models are combined, though any two of the above assumptions are compatible with it., 8 pages, 1 table and 6 figures

The synthesis and X-ray structure of a dinuclear nickel(II) complex of the triply deprotonated pentadentate Schiff base, N,N′-(2-hydroxypropane-1,3-diyl)bis(acetylacetoneimine) (apacaH3), are reported. The complex, which was obtained by reaction of apacaH3 with nickel acetate in ethanol, has a binuclear structure of type [Ni2 (apaca)(OAc)] in which each metal centre is bound to a deprotonated enolic oxygen and an imine nitrogen from an acetylacetoneimine ‘arm’ of apaca. The nickel centres are bridged by both an alkoxide oxygen derived from the 2-hydroxypropane unit in apaca and an acetato group. Each metal centre has a distorted square-planar geometry, with the overall configuration being non-planar. This complex is isostructural with a previously-reported, copper(II) complex of similar stoichiometry, prepared by an analogous procedure from copper(II) acetate. The present result contrasts with a previous report in which apacaH3 was claimed to interact with nickel(II) acetate in ethanol in the presence of potassium ethoxide to yield a square-planar complex of the corresponding doubly deprotonated Schiff base ligand.

A novel [1+1] Schiff-base macrocyclic compound 3 has been synthesized from precursor 1, 1,3-bis(2′-formylphenoxy)-2-propanol, and precursor 2, resorcinol-bis(4-aminophenyl)ether, via condensation and cyclizaction using Ba2+ as template. The macrocycle 3 was further reduced giving saturated macrocycle 4. The structures of 3 and 4 were characterized by elemental analysis, 1H NMR, IR, and MS spectra, and their structures were determined via single crystal X-ray diffraction studies. X-ray diffraction analysis revealed that the macrocyclic compound 3 has a folded conformation, and the corresponding reduced product 4 adopts a twisted and folded conformation due to its flexible nature.

The study aimed to investigate the comprehensive effect of digesting the dyestuff wastewater by the two methods of micro-electrocatalysis and SBR. The result of in-situ tests show that, micro-electrocatalysis had better color removal rate and could improve biodegradability remarkably, the combined system by micro-electrocatalysis and SBR could make the CODCr removal rate over 90% and discoloration rate up to 90%. So the combined system by the two methods could get great prospect of application in treating dyestuff wastewater.

Sensitization to perennial aeroallergens correlates with the risk of persistent asthma (AS) in children. In tropical Singapore, multiple codominant species of mites abound in the indoor environment, and preferential species-specific sensitization has been associated with different phenotypes of allergic disease. We investigated the pattern of mite component-specific IgE (mcsIgE) in children with different phenotypes of clinical allergic disease in an environment with multiple mite species exposure. A prospective evaluation of newly diagnosed patients with clinical diagnosis of allergic rhinitis (AR), atopic dermatitis (AD), or AS and sensitization to one or more aeroallergens were performed. Sera were tested for specific IgE against an extensive panel of Dermatophagoides pteronyssinus and Blomia tropicalis allergens. A total of 253 children were included, mean age 7.3 yr, 79% fulfilled criteria for AR, 46% AS, 71% AD, and 31% for all three. Sensitization to one or both mites was observed in 91% of children, 89% were sensitized to D. pteronyssinus, and 70% to B. tropicalis. The most common mite allergens recognized by these atopic children were Der p 1 (64%), Der p 2 (71%), Blo t 5 (45%), Blo t 7 (44%), and Blo t 21 (56%). Specific IgE responses to an increased number of distinct mite allergens correlated with the complexity of the allergic phenotype. In multivariate analysis, an increased risk for the multi-systemic phenotype (AR + AS + AD) was associated with sensitization to an increased repertoire of mite components (three or more) (OR 4.3, 95% CI 2.1-8.8, p = 0.001) and a positive parental history of AS (OR 2.4, 95% CI 1.2-2.9, p = 0.013). A highly pleiomorphic IgE response to the prevalent indoor mites is associated with the presence of a multi-systemic allergic phenotype in childhood in a tropical environment.

Diastereopure (1R,2R)-N,N'-bis(acetylacetone)cyclohexanedi-imine L(1) and its corresponding (1R,2R)L(1)/(1S,2S)L(2) enantiomeric mixture react with AgNO(3) to yield the unusual coordination polymer [Ag(2)(L(1))(L(2))(NO(3))(2)](n) (1) and the unique trimetallic discrete species {[Ag(3)(L(1))(3)(micro(3)-O,O,O-NO(3))(H(2)O)(3)](2)(NO(3))}(NO(3))(3) x 8.5H(2)O (2) which incorporates a symmetrical micro(3)-bridging nitrato group that gives rise to a C(3)-symmetric triskelion motif; both species also feature gamma-carbon eta(1) aryl-like coordination of neutral bridging acetylacetone-imine units to the respective Ag(I) centres.

The interaction of the diastereopure N,N'-bis(acetylacetone)cyclohexanediimine ligands, L(1)(1R,2R), L(2)(1S,2S), and their 1:1 mixture, with Zn(II) chloride has been investigated. Four new coordination polymers, [ZnL(1)Cl2 x H2O]n (1), [ZnL(2)Cl2 x H2O]n (2), [ZnL(2)Cl2]n (3), and [Zn6(L(2))6Cl12 x 2 H2O]n (4), each consisting of an infinite single helical chain displaying different pitches and/or handedness have been isolated. The complexed Schiff base ligands are present in their deprotonated enol forms, and the nitrogen atoms, which do not coordinate, are protonated because of proton transfer from the adjacent enol oxygen (coupled with concomitant N-H...O bond formation); each bound ligand is thus pseudo-zwitterionic. The respective zinc centers are bound to two chloro ligands and two oxygen donors from acacH-imine units belonging to different N,N'-bis(acetylacetone)cyclohexanediimine ligands such that the coordination at each zinc is distorted tetrahedral. Compounds 1 and 2, prepared from enantiopure L(1) and L(2), respectively, are enantiomers with similar structures, with the helical pitch in each being 17.0 A. Overall, the structure of 3 may be described as a one-dimensional helical chain with a pitch of 17.3 A, with each period corresponding to two L(2) ligands and two metal centers. The structure of [(Zn6L(2)6Cl12) x 2 H2O]n (4) contains six Zn(II) centers connected via six L(2) ligands to form a "bowed" helical repeat unit, with the pitch of the helix corresponding to 43.5 A. Supramolecular (intra- and intermolecular) aspects of all these unusual polymeric structures are discussed. Finally, the synthesis and characterization of an unprecedented six zinc-node discrete supramolecular assembly, [Zn6(L(1))3(L(2))3Cl12] (5), incorporating a 78-membered metallacycle, is also reported.