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Hard carbons hold great promise as the anode materials for sodium-ion batteries (SIBs), but the limited capacities and sluggish Na+ transfer kinetics still hinder their practical applications. These issues can be addressed from the perspective of improving the wettability of hard carbons with electrolyte. Herein, we demonstrate that the wettability of hard carbons can be regulated by tuning their pore size, so as to optimize their electrochemical properties. A series of N-doped hollow mesoporous carbon nanotubes (HMCNTs) with the average pore sizes in the range of 2–8 nm are synthesized. Among them, the HMCNTs with an average pore size of 6.1 nm (HMCNTs-6.1) exhibits the most improved wettability and reaction kinetics, which delivers a high reversible capacity (415.5 mA h g−1 after 100 cycles at 0.1 A g−1), superior long-term cycle stability and rate capability. In addition, as visualized by in situ transmission electron microscopy, the HMCNTs-6.1 with relatively large mesopores is more favorable for the mass transport across the carbon shells than the HMCNTs with smaller pore sizes. This work provides new insight for understanding the relationship between pore size, electrolyte wettability and electrochemical performance of porous hard carbon, which can help to design the high-performance SIB anodes. [ABSTRACT FROM AUTHOR]

Many caregivers of individuals who are frail and elderly face financial hardships that have negative consequences that compound over time. This article explores the causes of these hardships, reviews Medicaid home and community-based interventions, and related government financial supports that have been used to alleviate them and concludes with recommendations for social work practice and social policy. [ABSTRACT FROM AUTHOR]

Using data from a national sample of 451 single mothers collected 24 months during and after the Great Recession, this study tested four hypotheses related to comprehensive measures of employment problems, number of months without health insurance, and unmet medical or dental needs. The results indicate positive relationships between employment problems and unmet medical or dental needs, employment problems and lacking health insurance, and lacking health insurance and unmet medical or dental needs. Most important, lack of health care coverage significantly reduced the relationships between unemployment (by 26%) and underemployment (by 56%) and unmet medical or dental needs. These results indicate that lack of health insurance at least partially mediates the effects of employment problems on single mothers experiencing an unmet medical or dental need. The findings have implications for these mothers' medical and dental care access, which are discussed within the context of the recent health care reforms. [ABSTRACT FROM AUTHOR]

This study evaluated the clinical features, treatment strategies and outcomes of solid hemangioblastomas in 28 patients diagnosed with hypervascular lesions in the posterior fossa. Preoperative embolization of the feeding arteries had limited effects, with only 7 patients benefitting from it for the reduction of intraoperative hemorrhage. The tumor was completely removed in all patients, and 22 patients had a full recovery, while 6 patients, all of whom had van Hippel Lindau disease, developed recurrences. The present study demonstrated that meticulous en bloc surgical resection was the optimal treatment for solid hemangioblastomas of the posterior fossa. For large tumors, preoperative embolization was critical for preventing postoperative morbidity. Given the improvements in microsurgical techniques and the understanding of the tumor vascular pattern, total tumor removal associated with a low mortality rate could be achieved. [ABSTRACT FROM AUTHOR]

Two new isostructural coordination compounds exhibit the rare difunctional properties of both electron-transfer (ET) photochromism and ET thermochromism, which are significantly affected by halogen atoms. The thermocrystallographic studies of the same single crystal have elucidated the electron-donating nature of the halogen atoms. [ABSTRACT FROM AUTHOR]

Two novel manganese thioarsenates, {[Mn(2,2'-bipy)2(SCN)][Mn(2,2'-bipy)](AsVS4)}2 (1, 2,2'-bipy = 2,2'- bipyridine) and {[Mn(2,2'-bipy)2(SCN)]2[AsIII 2(S2)2S2]} (2), containing thiocyanate-modified Mn-2,2'-bipy complex cations were synthesized. They feature two terminal [Mn(2,2'-bipy)2(SCN)]+ complex cations bridged by a polyanion {[Mn(2,2'-bipy)]2(AsVS4)2}2- for 1 and a cyclic thioarsenate anion (AsIII2S6)2- for 2. In 2, the [AsIII2(S2)2S2]2- anion can be described as two (AsIIIS3)3- trigonal-pyramids interlinked through S-S bonds. The method to obtain new metal complex cations shown here, introducing an anionic second ligand to modify the number of coordination sites and the charges of the metal complex cations simultaneously, is different from the traditional methods, varying either the TM center or the organic ligand or employing mixed neutral organic ligands, and may open up a new route for preparing novel chalcogenidometalates. Compounds 1 and 2 exhibit wide optical gaps of 2.20 and 2.67 eV, respectively, and photoluminescence with the emission maxima occurring around 440 nm. Magnetic measurements show the presence of antiferromagnetic interactions between MnII centers in the two compounds. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to determine the prevalence of coronary angiographically evident atherosclerotic stenosis associated with myocardial bridging (MB) and to explore related risk factors of coronary artery stenosis located proximally to MB. Methods: Overall, 603 patients with MB-mural coronary arteries (MB-MCAs) diagnosed by angiography initially were enrolled in this observational study during May 2004 to May 2009. One-way ANOVA, t-test, Pearson correlation test and stepwise multiple regression analysis were performed to explore related risk factors. Results: Totally 644 MB-MCAs were examined. Prevalence of lesions located distally to MBs was significantly lower than those proximally to MBs [36 (5.9%) vs. 382 (62.4%), p<0.001]. Diastolic vessel diameters in MB segments were significantly smaller than reference segments p<0.001. Ulcer-like lesion was found in MB-MCA in 1 patient. Multivariate analysis suggested that vascular bifurcation lesions, the degree of narrowing and the number of diseased coronary vessels of non-MB-MCA arteries, age, low-density lipoprotein cholesterol (LDL-C)/high density lipoprotein cholesterol (HDL-C), male, course of diabetes, and systolic narrow rate (SNR) of MB-MCAs were positively related with the narrow degree of the first coronary artery stenosis (FCAS) located proximally to MBs (all p<0.05). Vascular bifurcation lesions, the degree of narrowing and the number of diseased coronary vessels of non-MB-MCA arteries, age, LDL-C/HDL-C, male, diabetes and dyslipidemia were positively related with the narrow degree of the most severe coronary artery stenosis(MSCAS) located proximally to MB (all p<0.05). Conclusion: The intramural and distal portions of a bridged artery are not the forbidden zone of artery atherosclerosis formation. SNR of MB-MCA may be one of the important decision factors to coronary artery stenosis located proximally to MB. [ABSTRACT FROM AUTHOR]

Herein the recent experiments performed by the authors on fabricated multi-walled BN nanotubes and monoatomic BN graphene-like nanosheets are reviewed. The results are presented in several sections, namely: (i) method for high-yield synthesis of thin, defect-free BN nanotubes of only a few-layers, with external diameters below 10 nm; (ii) verification of BN nanotube piezoelectrical behavior and its electrically-induced thermal decomposition under combined resistive heating and electrical charging in a transmission electron microscope; (iii) the first direct measurements of the true tensile strength and Young's modulus of BN nanotubes, using newly developed nanotensile tests inside an electron microscope; the measured values were found to be ∼30 GPa and ∼900 GPa, respectively; and (iv) diverse kinetic processes taking place within the prepared monoatomic BN sheets (so-called 'white graphenes') affiliated with intensive knock-on B and N atom displacements under high energy electron beam irradiation in an aberration-corrected medium-voltage high-resolution transmission electron microscope. [ABSTRACT FROM AUTHOR]

Two bifunctional 1H-tetrazolate-5-carboxylate ligands with different flexibilities, H2tza (1H-tetrazolate-5-acetic acid) and H2tzf (1H-tetrazolate-5-formic acid), were employed in the construction of zinc(II) complexes in the presence/absence of secondary ligands such as 2,2′-bipy and 4,4′-bipy. Three tza coordination polymers and two tzf dinuclear complexes, namely [Zn(tza)(H2O)]n(1), [Zn3(tza)2Cl2(2,2′-bipy)2(H2O)2]n(2), [Zn2(tza)2(4,4′-bipy)]n(3), [Zn(tzf)(H2O)3]2·2H2O (4) and [Zn(tzf)(2,2′-bipy)(H2O)]2·H2O (5), were hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Polymer 1is a 3-D two-fold interpenetrating diamond-like network with tetranuclear [Zn(COO)]4clusters as tertiary building units (TBUs) and µ3-κN3:κO2:κO1,N1 bridging tza as linkers. Polymer 2presents a 2-D structure formed by the linkage of 1-D Zn-carboxylate [Zn(COO)]nhelical chains and µ3-κN4:κO2:κO1,N1 bridging tza. In 3, 2-D (4,4) nets are built up with dinuclear [Zn(COO)]2clusters and µ3-κN4:κO2:κO1,N1 bridging tza, which are pillared through 4,4′-bipy to gain a 3-D self-penetrating LB-1 (446108) topology. In dinuclear complexes 4and 5, two Zn(II) atoms are bridged by a tzf ligand in a µ2-κN2:κO1,N1 fashion. The results denote that tetrazolate-5-carboxylate ligands can adopt variable coordination modes in the formation of the complexes, and different Zn-carboxylate aggregates can serve as tertiary building units (TBUs). The effects of the nature of tetrazolate-5-carboxylate ligands and secondary ligands, and hydrothermal reaction conditions on the structural topologies of the obtained complexes have been investigated. The photoluminescent properties and thermal stabilities of 1–5have also been discussed. [ABSTRACT FROM AUTHOR]

Using cyanide anions and sulfur simple substance as precursors of thiocyanate groups, three desired luminescent halogeno-thiocyano-d10metal complexes, namely, [Me4N][Cu(SCN)Br] (1) with a 1-D to 2-D architecture constructed through C–HBr hydrogen bonds, [Me4N][Cu(SCN)I] (2) with a 1-D to 3-D framework constructed through C–HI hydrogen bonds, and [Me4N][Ag2(SCN)2Cl] (3) with a special 3-D nanoporous structure constructed by µ-chloride atoms connecting the 2-D neutral ∞2[Ag2(SCN)2] layers, have been solvothermally synthesized and all exhibit efficient luminescence. The luminescent behavior of the three complexes was illustrated through the density functional theory. [ABSTRACT FROM AUTHOR]

A ferroelectric inorganic–organic hybrid based on in situsubstituted stilbazolium cation (TAMS2+= trimethylamino-N-methyl stilbazolium) has been obtained. Single-crystal X-ray structure analysis demonstrates that the NLO-phore organic component of the complex is embedded into the inorganic polymeric [Bi2Cl8]2−framework and shows a polar arrangement with the cooperation of the nonsymmetric inorganic component. The measurement of ferroelectric and nonlinear optical properties show typical ferroelectricity and second harmonic generation (SHG) responses as well as a significant improvement of the laser damage threshold and thermal stability of relative organic material. [ABSTRACT FROM AUTHOR]

A new mixed-framework mercury selenide diselenite, (Hg3Se2)(Se2O5) (1), has been prepared by a solid-state reaction and structurally characterized by single-crystal X-ray diffraction analysis. The crystal structure of 1 consists of parallel stair-like cationic (Hg3Se2)2+ chains, which are bridged by (Se2O5)2- anionic groups to form a novel 2-D layered mixed-framework. The optical properties were investigated in terms of the diffuse reflectance and microscopic infrared spectra. The electronic band structure along with density of states (DOS) calculated by the DFT method indicates that compound 1 is a semiconductor, and that the optical absorption of 1 is mainly ascribed to the charge transitions from the O-2p and Se(-II)-4p states to the Se(IV)-4p and Hg-6s states. [ABSTRACT FROM AUTHOR]

The reactions of TMA4Ge4S10 (TMA=tetramethylammonium), Cu(NO3)2·3H2O and 4,4'-bipy under hydrothermal environment result in the formation of (H2bipy)2Ge4S10·(bipy)·7H2O (1), which has been structurally characterized by single crystal X-ray analysis. The 3-D structure of 1 can be viewed as an inorganic-organic hybrid supramolecular hydrogen-bonding (hydrogen bonds: O–H···O, N–H···N, C–H···O, N–H···O, and O–H···S) and π-π stacking network containing Ge4S4−10 clusters and novel [H2bipy···bipy···H2bipy] trimers. [ABSTRACT FROM AUTHOR]

The stabilization of the (SnS4)4−anion in the coordination of [Mn(phen)]2+complexes brings about a novel compound {[Mn(phen)]2(SnS4)}n·nH2O (1), in which an unprecedented link mode of the (SnS4)4−anion is observed. Theoretical calculations indicate that TM complexes with big π-conjugated ligands, such as [Mn(phen)]2+, can serve as an excellent electron reservoir to stabilize the (SnS4)4−anion in 1, despite its strong condensation tendency. Magnetic measurements show the presence of strong antiferromagnetic interactions between the Mn2+ions in 1. [ABSTRACT FROM AUTHOR]

The first eight-coordinated trivalent lanthanide complexes with an achiral ligand 6,7-dicyanodipyridoquinoxaline (dicnq), [DyCl3(dicnq)2]n(1and 1′) were found to exhibit spontaneous chiral resolution, SHG active (two times that of KDP) and blue luminescence. [ABSTRACT FROM AUTHOR]

A novel chiral open-framework structural hexanary chalcogenoborate, (K3I)[SmB12(GaS4)3] (1), was obtained by a facile approach using boron as the reducing reagent; it shows weak SHG-activity and is transparent in the mid-IR region. [ABSTRACT FROM AUTHOR]

A novel 3-D (3,6)-connected topological architecture, obtained by reacting Cd(ClO4)2·6H2O with Htrtr (Htrtr = 3-(1,2,4-triazole-4-yl)-1H-1,2,4-triazole) under solvothermal conditions, presents a non-centrosymmetric polar packing arrangement, resulting in a strong second harmonic generation (SHG) response and ferroelectric property. [ABSTRACT FROM AUTHOR]

A novel 3-D (3,6)-connected topological architecture, obtained by reacting Cd(ClO4)2·6H2O with Htrtr (Htrtr = 3-(1,2,4-triazole-4-yl)-1H-1,2,4-triazole) under solvothermal conditions, presents a non-centrosymmetric polar packing arrangement, resulting in a strong second harmonic generation (SHG) response and ferroelectric property. [ABSTRACT FROM AUTHOR]