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The structure and magnetic properties of orthorhombic DyMnO3 nanoparticles with different particle sizes are investigated in this paper. With decreasing particle size, all the lattice parameters a, b, and c gradually decrease, whereas the orthorhombic distortion increases. Magnetic measurements reveal that the antiferromagnetic interaction of Mn ions is weakened due to the decrease in Mn-O-Mn bond angle. Above a critical field H*, DyMnO3 undergoes a field-induced metamagnetic transition at 4 K, which is related to the spin reversal of Dy moments. The critical field H* increases monotonically with size reduction, indicating an enhancement of the antiferromagnetic interaction of Dy ions due to the decreased distance between rare earth ions. The magnetization at 4K and 5 T, i.e., M(4K, 5 T) shows a non-monotonic variation with particle size d, i.e., M(4 K, 5 T) initially increases with size reduction but decreases again for d < 68 nm. A modified core-shell model, in which the ferromagnetic ordering (Dy magnetic structure) and antiferromagnetic ordering (Mn magnetic structure) coexist in the core, is proposed to explain this behavior. [ABSTRACT FROM AUTHOR]

A flexible bipyridinium ligand has been introduced into a series of isomorphous metal-organic frameworks to yield porous materials with subtriangular 1D channel and cagelike pore space. The introduction of bipyridinium molecules into the porous frameworks leads to the formation of 1D channel with positively charged surface, which shows high affinities to polar molecules such as methanol, ethanol, and water vapor. Additionally, the bipyridinium molecules possess conjugated pyridyl rings connected by carbon-carbon single bonds, which can rotate freely to keep twisted or large-conjugated planar configuration by controlling coordination condition during the self-assembly process. The cagelike pore space formed by these flexible bipyridinium molecules contains arene-arene stacked pyridyl rings and thus renders abundant π-π interaction sites for efficient adsorption of benzene and toluene molecules, and is also large enough to accommodate cyclohexane molecules. These metal-organic frameworks show efficient adsorption for benzene, toluene, and cyclohexane molecules through high utilization efficiency of unique pore space, and display rarely broad-spectrum adsorptivity to various organic pollutants with hydrophilic/hydrophobic, conjugated/nonconjugated characteristics. [ABSTRACT FROM AUTHOR]

The effective mechanical and acoustic properties of two-dimensional pentamode metamaterials (PMs) with different structural parameters are investigated in this paper. It is found that with varying structural parameters, the effective bulk modulus and density remain constant as the same as those of water, while the figure of merit, i.e., the ratio of the bulk modulus to the shear modulus (B/G) gradually increases due to the decrease of the shear modulus. However, full wave simulations reveal that with the increase of B/G, the acoustic scattering becomes more and more intense, which indicates that the acoustic properties of pentamode metamaterials gradually deviate from those of water. These anomalous acoustic behaviors are proposed to arise from the existence of the bending modes in pentamode microstructures. Our results show that for pentamode metamaterials, the mechanical properties cannot be simply translated to their acoustic properties, and the structural parameters affect the mechanical and acoustic properties in much different ways. [ABSTRACT FROM AUTHOR]

The effect of different concentrations of nickel ions (Ni2+ , 0, 10, 40 and 80 mg/L) on the anaerobic methane production of water hyacinth were investigated. Under these four concentrations, the methane production in 40 d was 2,275, 2,703, 3,210 and 2,481 mL, respectively. This situation illustrated that the NE2+ promoted the growth of hydrogen-producing acetic acid bacteria and methanogenic bacteria, even at high concentrations (i.e. 40-80 mg/L). The highest methane production per unit weight water hyacinth reached 206 mL/gTS with 40 mg/L Ni2+ . Meanwhile, the modified Gompertz and Logistic equations were applied to describe the effect on anaerobic culture of Ni2+. According to these models, the values of methane production potential (mL) for four concentrations were in the following order: 40 mg/L (3,123.42 ± 60.08)> 10 mg/L (2,541.16 ± 46.94)> 80 mg/L (2,432.36 ± 40.18) >0 mg/L (2,238.10 ± 31.90). According to the analysis of the digestate, the residual concentration of Ni2+ was approximately 1.05-4.9 mg/L, which was relatively low compared with the Ni2+ concentrations in the raw feedstock. The results would provide academic guidance and technical support for treatment of water hyacinth with an accumulation of heavy metals. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, [Cd2(C12H17N2O)2(C2H3O2)2]·H2O, the binuclear complex molecule as well as the water molecule occupy special positions on the same twofold axis. The CdII atom has a severely distorted octahedral coordination formed by two deprotonated bridging phenol O atoms, the imine and amine N atoms of the Schiff base and two O atoms of the chelating acetate group. The water H atom takes part in a hydrogen bond involving one of the acetate O atoms as an acceptor. Each water molecule forms two such bonds, thus producing isolated 1:1 complex molecule–water aggregates in the crystal structure. [ABSTRACT FROM AUTHOR]

The deprotonated 3-dimethyl­amino- N-salicylidenepropyl­amine Schiff base chelates to a Cd atom in the polymeric title compound with a dinuclear building block, [Cd2(NCS)2(C12H17N2O)2] n. The O atom of the Schiff base also engages in bridging. The bridging NCS group links adjacent dinuclear entities into a helical chain that runs along the b axis of the monoclinic unit cell. [ABSTRACT FROM AUTHOR]

Based on the Lewis acidic site and redox ability of bipyridinium ligand, a porous framework with an adsorption advantage for ammonia over water and color response ability has been constructed. The compound is highly stable and flexible to external stimuli, exhibiting reversible single-crystal-to-single-crystal transformations, in response to temperature change and NH3 capture. More attractively, the title compound shows obvious color change from yellow to dark blue when exposed to ammonia vapor within just a few seconds, indicating a strong ability to function as a visual colorimetric absorbent for ammonia. [ABSTRACT FROM AUTHOR]

A metal-organic framework (MOF) featuring intriguing Borromean entanglement exhibits a unique mechanochromic luminescence with on-off switching. The concomitant excitation wavelength-dependent emission behavior can be utilized to tune the emission color from violet to orange. [ABSTRACT FROM AUTHOR]

Objective: Telephone-administered therapies have emerged as an alternative method of delivery for the treatment of depression, yet concerns persist that the use of the telephone may have a deleterious effect on therapeutic alliance. The purpose of this study was to compare therapeutic alliance in clients receiving cognitive behavioral therapy (CBT) for depression by telephone (T-CBT) or face-to-face (FlF-CBT). Method: We randomized 325 participants to receive 18 sessions of T-CBT or FtF-CBT. The Working Alliance Inventory (WAI) was administered at Weeks 4 and 14. Depression was measured during treatment and over 1 year posttreatment follow-up using the Hamilton Rating Scale for Depression and Patient Health Questionnaire-9. Results: There were no significant differences in client or therapist WAI between T-CBT or FtF-CBT (Cohen's f2 ranged from 0 to .013, ail ps > .05). AH WAI scores predicted depression end of treatment outcomes (Cohen's f2 ranged from .009 to .06, all ps < .02). The relationship between the WAI and depression outcomes did not vary by treatment group (Cohen's f2 ranged from 0 to .004, ps > .07). The WAI did not significantly predict depression during posttreatment follow-up (all ps > .12). Conclusions: Results from this analysis do not support the hypothesis that the use of the telephone to provide CBT reduces therapeutic alliance relative to FtF-CBT. [ABSTRACT FROM AUTHOR]

Three metal-organic coordination compounds with different interpenetrating modes, [Cd(BCbpy)(BDC)].3H2O (1), [Cd2(BCbpy)2(BDC)Cl2][Cd(BCbpy)2(BDC)].18H2O (2), and [Cd(BCbpy)Cl2].3H2O (3) (HBCbpyCl = 1-(4-carboxybenzyl)-4,4-bipyridinium chloride, H2BDC = 1,4-benzenedicarboxylic acid), have been synthesized and structurally characterized. Compound 1 exhibits a 2D + 2D → 2D interpenetrating array with the coexistence of polyrotaxane and polycatenane structures. Compound 2 is an unprecedented example of a 2D + 2D + 1D → 2D interpenetrating structure which involves 2D + 2D → 2D parallel interpenetration and a 2D + 1D → 2D polyrotaxane. In the case of compound 3, the absence of the rod-like BDC ligand prevents threading through the ring-like units, no polyrotaxane structure is formed, and the compound features infinite 1D ring-containing chains arranged in parallel without any interpenetration. Interestingly, the structural transformation can be achieved through a solvent-mediated anion exchange process when compound 1 or 2 is exposed to the aqueous solution containing chloride ions. Upon progressive replacement of the BDC2- ligands by chloride ions, the complicated network topology is simplified and undergoes an evolution from interpenetration to non-interpenetration, accompanied by a visually observed on-off-on fluorescence switching. [ABSTRACT FROM AUTHOR]

A series of Mn-cpdba-2,2′-bpy complexes, {[Mn(cpdba)(2,2′-bpy)]}n1, {[Mn2(cpdba)2(2,2′-bpy)(H2O)2]·3H2O}n2, {[Mn2(cpdba)2(2,2′-bpy)2(H2O)2]·H2O}n3, {[Mn(cpdba)(2,2′-bpy)]·1.5H2O}n4, {[Mn4(cpdba)4(2,2′-bpy)3(H2O)2]}n5(H2cpdba = 4-(4-carboxyphenylamino)-3,5-dinitrobenzoic acid; 2,2′-bpy = 2,2′-bipyridine) have been synthesized at different temperatures under hydrothermal conditions. Complex 1has a 2D (4,4) network with alternate left and right-handed helical chains. With increasing temperature to 150 °C, complex 2, which has a complicated 3D framework constructed by a unique building block Mn3(cpdba)6(2,2′-bpy)2, can be obtained. Complex 3that has been reported previously was obtained at 160 °C. This complex exhibits a 1D chain structure which is extended into a 3D supermolecular framework by π–π stacking interactions. Complex 4was detected as a by-product in the synthesis of 3. X-Ray single crystal diffraction analysis reveals the formation of 2D layer network containing [Mn(CO2) + Mn(CO2)]ndouble-helices. With continuing increase to 170 °C, complex 5featuring 3D framework similar to 2, with the decrease in the coordinated water and lattice water molecules as well as increase in the regularity of the framework, was formed. Influence of the 2,2′-bpy co-ligand on the coordination configuration of the cpdba2−ligand has been discussed. The magnetic susceptibility measurements of 1and 5reveal that two complexes exhibit antiferromagnetic coupling interactions. [ABSTRACT FROM AUTHOR]

Two isomorphous 2D flexible metal–organic frameworks with [Cd2(μ2-X)2] (X = Cl or Br) units and dynamic 1D channels, which show tunable or switchable fluorescence signals in response to the loss of guest water molecules, have been synthesized and characterized. Especially, the chloride-bridged complex is found to be a selective fluorescence sensor for MeCN. [ABSTRACT FROM AUTHOR]

Luminescent supramolecular lanthanide edifices have many potential applications in biology, environments, and materials science. However, it is still a big challenge to improve the luminescent performance of multinuclear lanthanide assemblies in contrast to their mononuclear counterparts. Herein, we demonstrate that combination of intraligand charge transfer (ILCT) sensitization and coordination-driven self-assembly gives birth to bright EuIII tetrahedral cages with a record emission quantum yield of 23.1%. The ILCT sensitization mechanism has been unambiguously confirmed by both time-dependent density functional theory calculation and femtosecond transient absorption studies. Meanwhile, dual-responsive sensing toward both anions and cations has been demonstrated making use of the ILCT transition on the ligand. Without introduction of additional recognition units, high sensitivity and selectivity are revealed for the cage in both turn-off luminescent sensing toward I- and turn-on sensing toward Cu2+. This study offers important design principles for the future development of luminescent lanthanide molecular materials. [ABSTRACT FROM AUTHOR]

Aims To describe the prevalence and associations of epiretinal membrane (ERM) in an elderly urban Chinese population in China. Methods A population-based cross-sectional study was conducted using a cluster random sample of residents aged 50 years or older living in the Jiangning Road Sub-district, Shanghai, China. All participants underwent a standardised interview and comprehensive eye examinations, including digital retinal photography and spectral domain optical coherence tomography (SD-OCT) examinations of both eyes between November 2012 and February 2013. ERM was identified and classified as either cellophane macular reflex (CMR) or preretinal macular fibrosis (PMF) based on the fundus photography and OCT features. Results Of the 2044 subjects who participated (82.5% response rate), 2005 had fundus photographs and OCT results of sufficient quality for grading of ERM signs. ERM was present in 8.4% of participants, including 5.0% with CMR and 3.4% with PMF. After age and gender standardisation to the 2010 Chinese census population, the prevalence rate of ERM in mainland Chinese individuals of 50 years of age or older was estimated to be 7.3%. After adjusting for age and/or gender, idiopathic ERM was positively associated with age (OR, 1.06; 95% CI 1.04 to 1.08), female gender (OR 1.67, 95% CI 1.16 to 2.40), myopia (OR 2.21, 95% CI 1.51 to 3.22) and hyperlipaemia (OR 1.80, 95% CI 1.04 to 3.12). Conclusions The prevalence of ERM in elderly urban Chinese was similar to that in Caucasians. Risk factors for idiopathic ERM were older age, female gender, myopia and [ABSTRACT FROM AUTHOR]

Bright white-light emission was obtained from a novel pyridinium molecule by aggregation. Photophysical, single-crystal structural, and computational studies demonstrated that an additional low-energy emission was generated by the excitation of a new intermolecular charge-transfer (CT) band at the ground state that cooperates with the non-quenched high-energy monomer emission to produce white light. [ABSTRACT FROM AUTHOR]

Two bipyridinium-based metal-organic hybrid materials, {[Cd(Bpyen)0.5(p-BDC)(H2O)Br]·5H2O} (1) and {[Cd(Bpyen)(o-BDC)Br2]·8H2O} (2), have been synthesized. 1 is a 2D coordination polymer while 2 shows 1D chain-like structure. Both compounds exhibit rapid color change under light irradiation. However, the decolourization of the photochromic products is very different. The influence of the auxiliary ligands on the photochromism and decolourization process of the bipyridinium-based hybrid materials has been explored. Interestingly, water molecules are encapsulated in these two compounds and form novel water aggregates consisting of novel water building units, such as the (H2O)10 water cluster in 1 and the (H2O)12 water cages in 2 through hydrogen-bond interactions. The effect of these water aggregates on the stability of the two compounds has been studied. [ABSTRACT FROM AUTHOR]

Objective: According to the "antioxidants network" theory, the present study was conducted to evaluate the regulation of an antioxidant blend on intestinal redox status and major microbiota of early-weaned piglets. Methods: Piglets from 15 litters were randomly allocated by litter to the control group (suckling normally, fed the basal diet, n = 5), the weaning group (weaned at age 21 d, fed the basal diet, n = 5), and the repair group (weaned at age 21 d, fed the basal diet supplemented with an antioxidant blend, n = 5). The redox status and major microbiota in jejunum and colon tracts of 24-d-old piglets were detected, respectively. Results: Early weaning resulted in significant decreases in jejunum and colon antioxidant capacities, Lactobacillus and Bifidobacterium counts, and significant increases in levels of jejunum malondialdehyde, colon hydroxyl radicals, jejunum and colon H2O2, and Escherichia coli counts in piglets. The observed imbalance of the intestinal redox status and microbiota was significantly restored by the antioxidant blend. Interestingly, intestinal selected antioxidative items presented a positive correlation with potential beneficial bacteria and a negative correlation with E. coli. Nevertheless, selected oxidative items and the bacteria presented an inverse relationship in piglets. Conclusion: Supplementation of the antioxidant blend effectively restored intestinal redox status and microbiota balance in the porcine intestine in response to early weaning stress, enhancing intestinal health and function of piglets. [ABSTRACT FROM AUTHOR]

This was an in vitro and in vivo study to develop a novel artificial cervical vertebra and intervertebral complex (ACVC) joint in a goat model to provide a new method for treating degenerative disc disease in the cervical spine. The objectives of this study were to test the safety, validity, and effectiveness of ACVC by goat model and to provide preclinical data for a clinical trial in humans in future. We designed the ACVC based on the radiological and anatomical data on goat and human cervical spines, established an animal model by implanting the ACVC into goat cervical spines in vitro prior to in vivo implantation through the anterior approach, and evaluated clinical, radiological, biomechanical parameters after implantation. The X-ray radiological data revealed similarities between goat and human intervertebral angles at the levels of C2-3, C3-4, and C4-5, and between goat and human lordosis angles at the levels of C3-4 and C4-5. In the in vivo implantation, the goats successfully endured the entire experimental procedure and recovered well after the surgery. The radiological results showed that there was no dislocation of the ACVC and that the ACVC successfully restored the intervertebral disc height after the surgery. The biomechanical data showed that there was no significant difference in range of motion (ROM) or neural zone (NZ) between the control group and the ACVC group in flexion-extension and lateral bending before or after the fatigue test. The ROM and NZ of the ACVC group were greater than those of the control group for rotation. In conclusion, the goat provides an excellent animal model for the biomechanical study of the cervical spine. The ACVC is able to provide instant stability after surgery and to preserve normal motion in the cervical spine. [ABSTRACT FROM AUTHOR]

FT-IR, FT-Raman and electronic absorption spectroscopies were utilized in conjunction with density functional theory (DFT) calculations to investigate the ground and excited states of self-assembled dinuclear dimeric helicates (ZnL)2and (NiL)2L bis(2,4-dimethyldipyrrin-3-yl)methane. These studies afford a detailed description of the ground-state geometric and electronic structures of (ZnL)2and (NiL)2and provide a comparison with similar geometrical metal−porphyrins. The results demonstrate that enlarging the basis set used in the DFT calculations results in an obvious alteration of the calculated bond lengths but negligible alteration of the calculated bond angles. The predicted spectra are in good agreement with the experimental ones with the deviations generally less than 30 cm-1. In comparison with vibrational spectra of metal−porphyrins, the breathing vibration of the pyrrole ring is shifted by over 100 cm-1toward higher wavenumber due to local conjugation of molecular geometry. Time-dependent density functional theory (TD-DFT) provides a good description of the excitation energy. Because of the break in symmetry, the absorption band (corresponding to the Q-band of porphyrin) of (ZnL)2and (NiL)2is no longer weak. Local conjugation makes the absorption wavelength of (NiL)2and (ZnL)2shift to the blue compared with those of NiP and ZnP. [ABSTRACT FROM AUTHOR]