Factors influencing the level of insight and treatment attitude: a cross-sectional study of 141 elderly patients of major depression in Guangzhou, China.

Objective: To explore the insight, treatment attitude, and related influencing factors of hospitalized elderly patients suffering from major depression. Methods: A total of 141 hospitalized elderly patients with depression were selected as the research objects. Insight was evaluated by the total score of the Insight and Treatment Attitude questionnaire (ITAQ). The data collected included sociodemographic characteristics, psychiatric symptoms, delirium status, social functioning, social support, suicide risk, and cognitive function. Results: The sample included 74.5% of female patients, and the mean age was 67.53 (sd=7.19) years. The influencing factors of inpatients with depression included alcohol consumption, length of hospitalization, admission types, and the main caregivers (P<0.05). The various factors were further analyzed by linear regression, revealing that the insight and treatment attitude of elderly depressed hospitalized patients were mainly related to the Mini-Mental State Examination (MMSE) (ß= 0.225, 95% CI 0.055-0.395, P=0.01), dependent on a caregiver (ß=-5.810, 95% CI -8.086~-3.535, P<0.001), the type of admission (involuntary admission) (ß=-3.365, 95% CI -5.448~-1.283, P=0.002), Functional Activities Questionnaire (FAQ) (ß=-0.156, 95% CI -0.303~-0.010, P=0.037), and length of stay (≤28 days) (ß=2.272, 95% CI 0.055~-4.489, P=0.045). Conclusion: The level of insight was affected by cognitive function, involuntary admission, dependent on a caregiver, social function and length of stay. Future studies should focus on cognitive function recovery, observation of admission mode, and self-care ability in elderly patients with depression.

Superalkali halide perovskites with suitable direct band gaps for photovoltaic applications.

The construction of superalkali halide perovskites has attracted attention for the development of new photovoltaic materials, but stable superalkalis have not been found until now. Herein, to construct new three-dimensional superalkali halide perovskites with a MI3 frame (M = Sn and Pb), a new Li(H2O)3+ superalkali cation is designed and selected based on low vertical ionization potential, suitable tolerance factor, small ionic radius and large dissociation energy. High-throughput first-principles calculations show that superalkalis with lower vertical ionization potentials exhibit stronger interactions with the MI3 frame. The normal and cubic Li(H2O)3MI3 perovskites and cubic Li(H2O)4PbI3 perovskites have direct band gaps, s-p and p-p electron transitions, effective carrier masses of less than 0.45me and exciton binding energies of less than 291 meV. Moreover, the cubic Li(H2O)3PbI3 perovskite with a direct band gap of 1.40 eV can in theory show a power conversion efficiency of 33.49%. These results strongly suggest that superalkali cations with large dissociation energy can be used to develop stable superalkali perovskites for photovoltaic applications.

Effectiveness of nurse-delivered stepwise swallowing training on dysphagia in patients with Alzheimer's disease: A multi-center randomized controlled trial.

BACKGROUND: Although swallowing exercises are a fundamental treatment for dysphagia, few studies have evaluated the effectiveness of swallowing training in patients with Alzheimer's disease. METHODS: We recruited 93 patients with Alzheimer's disease from three hospitals in Guangdong, China. This was a parallel armed randomized controlled trial that randomly assigned patients to intervention (n = 48) and control (n = 45) groups. The intervention group adopted systematic stepwise swallowing training for four weeks based on routine dysphagia care. The control group implemented routine dysphagia care, including diet and posture management and health education about swallowing dysfunction. The swallowing function was the primary outcome, which was assessed using the Water Swallowing Test and Standard Swallowing Assessment. An abnormal eating behavior questionnaire was used to assess the incidence of aberrant eating behavior in patients with Alzheimer's disease. The Mini-Nutritional Assessment Short Form and Barthel index were adopted to evaluate the nutritional status and ability to carry out daily activities between groups. SPSS software was used to perform the chi-square test, t-test, and generalized estimation equation for data analysis. RESULTS: We analyzed the effects of the stepwise swallowing training program using the generalized estimating equation method. The intervention group exhibited greater improvements in their swallowing function (Water Swallowing Test: ß = -3.133, 95 % CI: -4.113, -2.154, P < 0.001; Standard Swallowing Assessment: ß = -5.813, 95 % CI: -7.782, -3.844, P < 0.001), abnormal eating behaviors (abnormal eating behavior questionnaire: ß = -13.324, 95 % CI: -21.643, -5.005, P = 0.002), daily function (Barthel index: ß = 11.280, 95 % CI: 4.021, 18.540, P = 0.002), and nutritional status (Mini-Nutritional Assessment Short Form: ß = 2.402, 95 % CI: 1.313, 3.490, P < 0.001) over time than the routine-care group in the fourth week. CONCLUSIONS: Stepwise swallowing training is a safe and effective intervention for managing dysphagia and other related symptoms in patients with Alzheimer's disease.

Atomically thin two-dimensional hybrid perovskites using hydrophobic superalkali cations with tunable electron transition type.

The direct band gaps of two-dimensional (2D) metal halide perovskites can be tuned via component engineering, but their electron transition type hardly changes. Herein, atomically thin (C5NH6)2MX4 (M = Ge, Sn, Pb; X = Cl, Br, I) hybrid perovskites with hydrophobic superalkali cations were systematically explored using high-throughput hybrid density functional calculations and ab initio molecular dynamics simulations. We found that the electron transition between the M and X atoms was converted into that between the C5NH6 parts and X atoms via X change in the 2D (C5NH6)2MX4 perovskites. Negative formation energy, stable thermodynamic and kinetic properties, sharp valence bands, and tunable direct band gaps were obtained for the 2D perovskites. A power conversion efficiency (PCE) of 32.54% was obtained in theory for the passivated cubic NH2CHNH2PbI3 (FAPbI3) perovskite containing the 2D (C5NH6)2PbI4 perovskite. The hybrid Pb-free (C5NH6)2SnI4 perovskite with a direct bandgap of 1.56 eV may be viewed as a potential passivation material for perovskite devices. Moreover, the C5NH6 cations and X atoms show different hydrogen bonding interactions, which can be extended to other atomically thin organic-inorganic hybrid perovskites.

Passivating Lead Halide Perovskites Using Pyridinium Salts with Superhalogen Atoms.

Passivating lead halide perovskites using pyridinium salts has attracted enormous attention, but the excellent surface passivation of the halide perovskites has not been achieved by using only a pyridinium salt until now. Herein, passivating the (001) planes of the cubic CsPbI3, CH3NH3PbI3, and NH2CHNH2PbI3 perovskites using the pyridinium salts of C5NH6X (X = Cl, Br, I, PF6, ClO4, or BF4) is systematically studied by high-throughput first-principle calculations and ab initio molecular dynamics simulations. The results show that the excellent surface passivation of the three perovskites is achieved by the pyridinium salt of C5NH6BF4 (i.e., shallow level, negative formation energy, unchanged band-edge construction, and stable dynamics property are obtained for the three passivated perovskites), which strongly imply that their devices can show excellent performances, such as long-term stability, low ion migration, and high efficiency. However, the C5NH6ClO4 and C5NH6PF6 pyridinium salts are only profitable for passivating the (001) PbI2 plane of the three perovskites, and other C5NH6X pyridinium salts have adverse effects.

Quasi-2D lead-free halide perovskite using superalkali cations for red-light-emitting diodes.

Two dimensional halide perovskites have attracted intense attention, but there is no study to consider quasi-2D lead-free perovskites with superalkali cations as potential emitting materials. Herein, the quasi-2D [C6H5(CH2)2NH3]2H5O2Sn2Br7 perovskite is systematically studied by using ab initio molecular dynamics simulation and first principles calculations. The calculated results show that the quasi-2D perovskite has negative formation energy, small effective hole and electron masses, stable dynamics performance, suitable exciton binding energy and direct band gap, and H5O2 superalkali cations that don't agglomerated. Moreover, the band-edge states do not change for the quasi-2D perovskite after ab initio molecular dynamics simulation of 3 ps. Overall, our results indicated that the quasi-2D [C6H5(CH2)2NH3]2H5O2Sn2Br7 perovskite may be applied to red-light-emitting diodes.

Two dimensional CdS/ZnO type-II heterostructure used for photocatalytic water-splitting.

The electronic structures of two dimensional (2D) CdS/ZnO heterostructure (CdZnHT) consisting of CdS singlelayer (SL) and ZnO SL are explored based on hybrid density functional calculation. The negative interface formation energies suggest the formation of CdZnHT is exothermic. The bandgap of CdZnHT is favorable for absorbing visible light, and the decent band edge position makes it thermodynamically feasible for spontaneous generation of oxygen and hydrogen. The formed electric field across the interface induced by charge transfer will reduce photogenerated carrier recombination and promote carrier migration. Particularly, CdZnHT is a type-II heterostructure. Oxygen generation takes place at ZnO layer and hydrogen production occurs at CdS layer, which will also promote the effective separation and migration of phogogenerated carriers and enhance photocatalytic performance. These findings suggest that 2D CdZnHTs are possible candidates as water-splitting photocatalysts.

Robust spin manipulation in 2D organometallic Kagome lattices: a first-principles study.

The search for 2D ferromagnets with versatile magneto-electronic properties is becoming more active due to their potential applications in spintronic devices. To screen out the optimal compositions, we have explored a series of two-dimensional M3C12X12 (M = 5d transition metals, and X = S, NH, and O) metal-organic frameworks with Kagome lattice patterns through first-principles calculations. By varying the metal center and ligand functional radicals, both the electronic and spin-related properties can be easily tuned to meet the requirements for multifunctional applications in spintronic devices. Among them, Re3C12N12H12 is identified to be a ferromagnetic bipolar magnetic semiconductor with the highest Curie temperature (TC > 330 K). Re3C12O12 is found to be an ideal half-metal with a spin gap of 0.97 eV, which is beneficial for use as a spin-filter. Meanwhile, both Re3C12N12H12 and Re3C12O12 exhibit considerable out-of-plane magnetic anisotropy energies (>26 meV per atom), which benefit the spintronic applications. The theoretical results not only show that the 2D organometallic Kagome lattice is a good platform for designing spintronic materials, but also provides a feasible way to realize robust spin manipulation.

A two-dimensional CdO/CdS heterostructure used for visible light photocatalysis.

Based on hybrid density functional calculations, the geometrical and electronic structures of a two-dimensional (2D) CdO/CdS heterostructure (HT) formed by a CdO monolayer (ML) and a CdS ML are investigated. The formation of the CdO/CdS HT is exothermic, and the CdO/CdS HT shows excellent ability for visible light absorption. The CdO/CdS HT with a rotation angle of 0° possesses the characteristics of type-II band alignment and strong built-in electric field across the interface, which boost the photogenerated carrier separation. Besides, the band edge positions of the CdO/CdS HT of 0° are energetically favorable for overall water-splitting processes with the pH scope of 0-3.6. Therefore, the CdO/CdS HT is a promising photocatalyst to split water.

Ultrastable CsPbBr3 Perovskite Quantum Dot and Their Enhanced Amplified Spontaneous Emission by Surface Ligand Modification.

The poor stability and aggregation problem of CsPbBr3 quantum dots (QDs) in air are great challenges for their future practical application. Herein, a simple and effective ligand-modification strategy is proposed by introducing 2-hexyldecanoic acid (DA) with two short branched chains to replace oleic acid (OA) with long chains during the synthesis process. These two short branched chains not only maintain their colloidal stability but also contribute to efficient radiative recombination. The calculations show that CsPbBr3 QDs with DA modification (CsPbBr3 -DA QDs) have larger binding energy than CsPbBr3 QDs with OA (CsPbBr3 -OA QDs), resulting in significantly enhanced stability. Due to the strong binding energy between DA ligands and QDs, CsPbBr3 -DA QDs exhibit no aggregation phenomenon even after stored in air for more than 70 d, and CsPbBr3 -DA QDs films can maintain 94.3% of initial PL intensity after 28 d, while in CsPbBr3 -OA QDs films occurs a rapid degradation of PL intensity. Besides, the enhanced amplified spontaneous emission (ASE) performance of CsPbBr3 -DA QDs films has been demonstrated under both one- and two-photon laser excitation. The ASE threshold of CsPbBr3 -DA QDs films is reduced by more than 50% and their ASE photostability is also improved, in comparison to CsPbBr3 -OA QDs films.

Two-dimensional Au-1,3,5 triethynylbenzene organometallic lattice: Structure, half-metallicity, and gas sensing.

On the basis of first-principles calculations, we investigated the structural and electronic properties of the two-dimensional (2D) Au-1,3,5 triethynylbenzene (Au-TEB) framework, which has been recently synthesized by homocoupling reactions in experiments. Featured by the C-Au-C linkage, the 2D Au-TEB network has a kagome lattice by Au atoms and a hexagonal lattice by organic molecules within the same metal-organic framework (MOF), which exhibits intrinsic half-metallicity with one spin channel metallic and the other spin channel fully insulating with a large energy gap of 2.8 eV. Two branches of kagome bands are located near the Fermi level, with each branch including one flat band and two Dirac bands, which originates from the out-of-plane dxz and dyz orbitals of Au and may lead to many exotic topological quantum phases. We further studied the adsorption of F atoms, Cl atoms, and small gas molecules including O2, CO, NO2, and NH3 on the Au-TEB network, aiming to exploit its potential applications in gas sensors. Detailed analyses on adsorption geometry, energy, molecular orbital interaction, and electronic structure modification suggest the great potential of Au-TEP as a promising alternative for gas sensing. We expect these results to expand the universe of low-dimensional half-metallic MOF structures and shed new light on their practical applications in nanoelectronics/spintronics.

Strain-engineered two-dimensional MoS2 as anode material for performance enhancement of Li/Na-ion batteries.

Recent years have witnessed a surge of research in two-dimensional (2D) nanostructures for development of new rechargeable Li/Na-ion battery systems. Herein, via first-principles calculations we demonstrate strain-engineered Li/Na adsorption and storage in 2D MoS2 as anode material, aiming to enhance the operating performance of Li/Na-ion batteries. Our results show that tensile strain greatly increases the adsorption of Li/Na atoms on MoS2, and a modest strain of 6% increases Li (Na) adsorption energy by over 70%, which originates from the strain-induced upshift of Mo d states towards Fermi level that interact strongly with Li/Na s states, in analogy with the d-band model in metal catalyst. Significant narrowing of the n-doped semiconducting gap of MoS2 suggests the improved electric conductivity that may benefit charge carrier transport. By mapping out the potential energy surfaces, we show shallow energy barriers of ion diffusion with ~0.2 eV for Li and 0.1 eV for Na. Furthermore, the strain-steered competition between chemical bonding and coulomb repulsion results in high Li/Na storage capability and relatively low average operating voltage. We believe that the fundamental principle underlying the use of strain to enhance performance of renewable ion battery is applicable to other stretchable low-dimensional nanomaterials.