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Reaction of M(OAc)2·xH2O (M, x = Zn, 2 and Co, 4), 1,4-dihydro-5,6-dicyano-2,3-pyrazinedione (H2CN2pyzdione), and pyrazine (pyz) affords two compounds of the same molecular formula {[M(H2O)6][M(CN2pyzdione)2(pyz)]·6H2O}n (M = Zn for 1 and Co for 2) in which discrete units of [M(H2O)6]2+ are linked to one-dimensional chains of [M(CN2pyzdione)2(pyz)]2– via multiple O–H···O hydrogen-bonding interactions and M2+-bound H2O molecules in [M(H2O)6]2+ also serve as linkers of hydrogen-bonded interstitial H2O molecules. Remarkably, 1 crystallizes in the monoclinic crystal system, the similar crystal system and unit cell parameters as 2, but with a space group distinct from 1 and 2, i.e., 1 is the noncentrosymmetric space group C2, whereas 2 is the centrosymmetric space group C2/m. This polar structure for 1 is induced by the presence of alternating arrangements of distinguishable two axial Zn–N bonds within [Zn(CN2pyzdione)2(pyz)]2– chains. Indeed, solid-state circular dichroism spectra of 1 exhibit significant Cotton effects, as evidenced by the polar space group C2. Moreover, these Cotton effects show clear temperature-dependence depending on contents of H2O molecules of 1. [ABSTRACT FROM AUTHOR]

The relationships between the host structure of iron-chloranilate layers and the intercalated charged guests are described. Study shows that hydrogen-bond supported anionic layers based on iron-chloranilate mononuclear complexes can be used as inorganic hosts for the intercalation of guest cations to construct new types of multilayered inorganic-organic hybrid materials.

The synthesis and characterization of two members of a family of porous magnetic materials and the interactions between the pillaring agent and the compositionally complex inorganic layer are described. The magnetism of the pillared layered cobalt hydroxides is complex due to the influences of multiple metal sites, inter- and intralayer exchange, spin-orbit coupling and geometrical frustration, and the controlling influence of the rigidity of the organic pillar on the chemistry and its influence on the cooperative magnetism are shown.

The synthesis and characterization of three coordinated networks having the dimeric [Cu.sub.2][(C[O.sub.2]).sub.4] node connected by different geometrical isomers of cyclohexane carboxylates is presented. The results have shown that the magnetic properties of all the three compounds are dominated by the strong Cu-Cu antiferromagnetic interaction resulting in singlet-triplet gaps.

The hydrothermal reaction of nickel(II) and mixtures of geometric isomers of 1,4-Cy-clohexanedicarboxylate results in total segregation in the solids based on a common Ni3(OH)2 linear chain secondary building unit connected by the fully deprotonated acid to form 3D frameworks with channels containing water molecules. Both are magnetic at low temperatures and one displays a reversible transformation from a ferrimagnet to ferromagnet upon partial hydration and rehydration.

Two weakly coupled paramagnetic polymorphs of M(super II)-(trans-3)(3-pyridyl)acrylate)(H2O)(sub 2) were selectively prepared hydrothermally at 120 and 170 degree Celsius. The structures consisted of wither an unusual network showing threadings of three sublattices and knots in one case and a Zwitterionic chain for the other, respectively.

The findings of a synthesis and characterization of two new copper II compounds are presented. The contents, structure and formation of these crystals are also explained.

Research has been conducted on porous magnetic material that orders ferrimagnetically at 60.5 K. The authors describe the results of synthesis and characterization of this material.

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system (Cas) is widely used for mediating the knock-in of foreign DNA into the genomes of various organisms. Here, we report a process of CRISPR/Cas-mediated knock-in via non-homologous end joining by the direct injection of Cas9/gRNA ribonucleoproteins (RNPs) in the crustacean Daphnia magna, which is a model organism for studies on toxicology, ecology, and evolution. First, we confirmed the cleavage activity of Cas9 RNPs comprising purified Cas9 proteins and gRNAs in D. magna. We used a gRNA that targets exon 10 of the eyeless gene. Cas9 proteins were incubated with the gRNAs and the resulting Cas9 RNPs were injected into D. magna eggs, which led to a typical phenotype of the eyeless mutant, i.e., eye deformity. The somatic and heritable mutagenesis efficiencies were up to 96% and 40%, respectively. Second, we tested the CRISPR/Cas-mediated knock-in of a plasmid by the injection of Cas9 RNPs. The donor DNA plasmid harboring the fluorescent reporter gene was designed to contain the gRNA recognition site. The co-injection of Cas9 RNPs together with the donor DNAs resulted in generation of one founder animal that produced fluorescent progenies. This transgenic Daphnia had donor DNA at the targeted genomic site, which suggested the concurrent cleavage of the injected plasmid DNA and genomic DNA. Owing to its simplicity and ease of experimental design, we suggest that the CRISPR/Cas-mediated knock-in method represents a promising tool for studying functional genomics in D. magna. [ABSTRACT FROM AUTHOR]

Relation between the thermodynamic parameters obtained from water sorption isotherms and the degree of reduction in the glass transition temperature (Tg), accompanied by water sorption, was quantitatively studied. Two well-known glassy food materials namely, wheat gluten and maltodextrin were used as samples. The difference between the chemical potential of water in a solution and that of pure water (), the difference between the chemical potential of solid in a solution and that of a pure solid (), and the change in the integral Gibbs free energy () were obtained by analyzing the water sorption isotherms using solution thermodynamics. The parametercorrelated well with ?Tg(?Tg ? Tg0; whereTg0is the glass transition temperature of dry material), which had been taken to be an index of plasticizing effect. This indicates that plasticizing effect of water on foods can be evaluated through the parameter. [ABSTRACT FROM PUBLISHER]

The proton conducting properties of two different structural types of porous coordination polymers [La2(ox)3(H2O)6]·4H2O (1) and [Er2(ox)3(H2O)6]·12H2O (2), where ox2− = oxalate, were investigated. 1 has a two-dimensional layered structure, whereas 2 has a three-dimensional structure. Both 1 and 2 have hydrophilic one-dimensional channels filled by lattice water molecules with hydrogen-bonding networks. The coordinated H2O molecules are Lewis acidic due to the lanthanoid ions donating protons to lattice-filling H2O molecules, thereby forming efficient proton conduction pathways. Alternating-current impedance analyses of 1 and 2 indicated significant proton conduction (σ = 3.35 × 10−7 S cm−1 at 368 K for 1, 1.79 × 10−6 S cm−1 at 363 K for 2 under RH = 100%, with Ea = 0.35 eV for 1 and 0.47 eV for 2), which was attributed to the Grotthuss mechanism via the lattice H2O molecules. [ABSTRACT FROM AUTHOR]

A novel electrochemical ionic liquid membrane reactor capable of separating NO from a mixture of NO and oxygen with high current efficiency at low temperatures was designed and tested. This reactor consists of a combination of an ionic liquid and a thin film of anodised alumina with two platinum electrodes. During operation of the reactor, NO is electrically transported from the cathode side to the anode side. [ABSTRACT FROM AUTHOR]

The article presents a study concerning the relationship between velocity and rheological properties of thickener solutions. The study arouses from proper physical properties of food for patients with difficulty in swallowing. It involves the use of ultrasonic pulse doppler method to measure the said relationship through the pharynx.

Single crystals of three coordination networks containing the Cu2(COO)4 core bridged by cyclohexane have been hydrothermally prepared by the reaction of 1,4-cyclohexanedicarboxylic (1,4-H2chdc) or 1,3,5-cyclohexanetricarboxylic (1,3,5-H3chtc) acid and Cu(NO3)2·6H2O. We report their characterizations by single-crystal X-ray structure determinations, IR spectroscopy, thermal analyses, and their magnetic properties. [Cu2(trans-1,4-chdc)2] (1) consists of 4 × 4 grids with the dimeric nodes connected by the trans-1,4-chdc, and these grids are then connected to each other by Cu-O bonds, resulting in a porous network (void volume of 130 ų per cell or 25%) with no solvent in its cavities. [Cu2(cis-1,4-chdc)2(H2O)2] (2) consists of two-legged ladders where the dimer nodes are bridged by pairs of cis-1,4-chdc and the water molecules cap the ends of the Cu dimers. [Cu2(1,3,5-Hchtc)2] (3) displays 4 × 4 grids, but each dimeric node is connected to its neighbors within the same grid by Cu-O bonds to form a layered network which further makes hydrogen-bond interactions with its neighbors. 2 and 3 have compact structures without any space for solvents. IR and DT-TGA confirm the absence of water in the empty channels of 1, while IR shows the presence of both protonated and deprotonated carboxyl groups for 3. The magnetic properties of all three compounds are dominated by the strong Cu-Cu antiferromagnetic interaction resulting in singlet-triplet gaps of 450-500 K. [ABSTRACT FROM AUTHOR]

The article evaluates the allergenicity of the gliadin using sera from patients RAST-positive to wheat. According to the authors, the addition of cysteine before the treatment with a cation exchanger effectively increased the deamidation level of gliadin. They add deamidated gliadin showed higher solubility than the undeamidated form. They also mention that rats administered with deamidated gliadin showed suppressed elevation of the gliadin-specific immunoglobulin E level.

Soybean proteins were deamidated by cation-exchange resins after phytate, the inhibitor for calcium absorption from the small intestine, was removed in order to provide the enhancement function of calcium absorption to soybean proteins. About 92% of the phosphorus was removed from the soybean proteins by anion-exchange-resin treatment, indicating that most of the phytate was removed. About 70% of the acid amide was deamidated by cation-exchange-resin treatment, and phytate-removed and deamidated soybean proteins (PrDS) having high calcium binding properties were obtained. PrDS were hydrolyzed by digestive enzymes and their calcium-binding properties and the enhancement function of the calcium absorption from the small intestine of rats were examined. As a result, PrDS retained their high calcium binding properties even after hydrolysis by digestive enzymes. In situ experiments showed that PrDS and their hydrolysates enhanced the calcium absorption from the intestine. [ABSTRACT FROM AUTHOR]

Describes the synthesis, characterization and reversible guest-exchange chemistry of a porous Cobalt(II)-hydroxide layer structure pillared with trans-1,4-cyclohexanedicarboxylate magnetic material that orders ferrimagnetically. In-situ single crystal and powder X-ray diffraction analyses; Decrease in interlayer spacing; Loss of two water molecules per formula unit; Single crystal structure of the fully dehydrated material.