Efficient degradation of organics by ultrasonic piezoelectric effect on CuO-BTO/AFC composite.

The recombination of photoexcited electron-hole pairs greatly limits the degradation performance of photocatalysts. Ultrasonic cavitation and internal electric field induced by the piezoelectric effect are helpful for the separation of electron-hole pairs and degradation efficiency. The activated foam carbon (AFC) owing to its high surface area is often used as the substrate to grow catalysts to provide more reactive active sites. In this work, CuO@BaTiO3(CuO@BTO) heterostructure is prepared by hydrothermal method on the surface of AFC to investigate the ultrasonic piezoelectric catalysis effect. X-ray diffraction (XRD), Raman spectroscopy, energy dispersive x-ray spectroscopy (EDS) and scanning electron microscopy (SEM) were used to analyze the structure and morphology of CuO-BTO/AFC composite. It is found that the CuO-BTO/AFC composite exhibits excellent piezo-catalytic performance for the degradation of organics promoted by ultrasonic vibration. The CuO-BTO/AFC composite can decompose methyl orange and methylene blue with degradation efficiency as high as 93.9% and 97.6% within 25 min, respectively. The mechanism of piezoelectricity enhanced ultrasound supported catalysis effect of system CuO-BTO/AFC is discussed. The formed heterojunction structure between BTO and CuO promotes the separation of positive and negative charges caused by the piezoelectric effect.

Strain Tunable Thermoelectric Material: Janus ZrSSe Monolayer.

Thermoelectric (TE) performance of the Janus ZrSSe monolayer under biaxial strain is systematically explored by the first-principles approach and Boltzmann transport theory. Our results show that the Janus ZrSSe monolayer has excellent chemical, dynamical, thermal, and mechanical stabilities, which provide a reliable platform for strain tuning. The electronic structure and TE transport parameters of the Janus ZrSSe monolayer can be obviously tuned by biaxial strain. Under 2% tensile strain, the optimal power factor PF of the n-type-doped Janus ZrSSe monolayer reaches 46.36 m W m-1 K-2 at 300 K. This value is higher than that of the most classical TE materials. Under 6% tensile strain, the maximum ZT values for the p-type- and n-type-doped Janus ZrSSe monolayers are 4.41 and 4.88, respectively, which are about 3.83 and 1.49 times the results of no strain, respectively. Such high TE performance can be attributed to high band degeneracy and short phonon relaxation time under strain, causing simultaneous increase of the Seebeck coefficient and suppression of the phonon thermal transport. Present work demonstrates that the Janus ZrSSe monolayer is a promising candidate as a strain-tunable TE material and stimulates further experimental synthesis.

First-principle study of neutron irradiation induced performance degradation of amorphous porous silica.

Neutron irradiation induced degradation of porous silica film is studied by Molecular Dynamics and Density-Functional theory-based methods. The degradation of microscopic structure, thermal property, and optical property of porous silica film are systematically investigated. Low-energy recoil is used to simulate the neutron irradiation effect. The pair and bond angle distributions, and coordination number distributions reveal that, under neutron irradiation, the microscopic structure of porous silica film is obviously modified, and the coordination defects are induced. We find that the higher recoil energy, the more coordination defects are formed in the film. The increased defects lead to a decrease in thermal conductivity. In addition, neutron irradiation induces additional optical absorption peaks in UV region and increasement in refractive index, resulting in a noticeable reduction in light transmittance. The detailed calculation of density of states reveals that these optical absorption peaks originate from the irradiation induced defect states in band gap. Our work shows that low-energy neutron irradiation can induce obvious defect density and degrade thermal and optical properties of porous silica film, which are responsible for subsequent laser-induced damage.

Strong UV laser absorption source near 355 nm in fused silica and its origination.

As a high-performance optical material, fused silica is widely applied in high-power laser and photoelectric systems. However, laser induced damage (LID) of fused silica severely limits the output power and performance of these systems. Due to the values in strong field physics and improving the load capacity and performance of high power systems at UV laser, LID at 355 nm of fused silica has attracted much attention. It has been found that, even be treated by advanced processing technologies, the actual damage threshold of fused silica at 355 nm is far below the intrinsic threshold. It means that there is an absorption source near 355 nm in fused silica. However, to date, the absorption source is still unknown. In this paper, a absorption source near 355 nm is found by first-principles calculations. We find that the absorption source near 355 nm is neutral oxygen-vacancy defect (NOV, ≡Si-Si≡) and this defect originates from the oxygen deficiency of fused silica. Our results indicate that NOV defect can be taken as a damage precursor for 355 nm UV laser, and this precursor can be obviously reduced by increasing the ratio of oxygen to silicon. Present work is valuable for exploring damage mechanisms and methods to improve the damage threshold of fused silica at UV laser.

Effects of Se substitution and transition metal doping on the electronic and magnetic properties of a MoSxSe2-x/h-BN heterostructure.

The van der Waals heterostructures created by stacking two monolayer semiconductors have been rapidly developed experimentally and exhibit various unique physical properties. In this work, we investigate the effects of Se atom substitution and 3d-TM atom doping on the structural, electronic, and magnetic properties of the MoSe2/h-BN heterostructure, by using first-principles calculations based on density functional theory (DFT). It is found that Se atom substitution could considerably enhance the band gaps of MoSe2/h-BN heterostructures. With an increase in the substitution concentration, the energy band changes from an indirect to a direct band gap when the substitution concentration exceeds a critical value. For 3d-TM atom doping, it is shown that V-, Mn-, Fe-, and Co-doped systems exhibit a half-metallic state and magnetic behavior, while there is no spin polarization in the Ni-doped case. The results provide a theoretical basis for the development of diluted magnetic semiconductors and spin devices based on the MoSxSe2-x/h-BN heterostructure.

Design of an Oxide Monolayer with High ZT by a Strong Anharmonicity Unit.

In this paper, a new strategy to obtain a transition-metal oxide (TMO) thermoelectric monolayer is demonstrated. We show that the TMO thermoelectric monolayer can be achieved by the replacement of a transition-metal atom with a cluster, which is composed of heavy transition atoms with abundant valence electrons. Specifically, the transition-metal atom in the XO2 (X = Ti, Zr, Hf) monolayer is replaced by the [Ag6]4+ cluster and a stable structure Ag6O2 is achieved. Due to the abundant valence electrons in the [Ag6]4+ cluster unit, n-type Ag6O2 has high electrical conductivity, which leads to a satisfactory power factor. More importantly, Ag6O2 has an extremely low phonon thermal conductivity of 0.16 W·m-1·K-1, which is one of the lowest values in thermoelectric materials. An in-depth study reveals that the extremely low value originates from the strong phonon anharmonicity and weak metal bond of the [Ag6]4+ cluster unit. Due to the satisfactory power factor and ultralow phonon thermal conductivity, Ag6O2 has high ZT at 300-700 K, and the maximum ZT is 3.77, corresponding to an energy conversion efficiency of 22.24%. Our results demonstrate that replacement of the transition-metal atom by an appropriate cluster is a good way to obtain a TMO thermoelectric monolayer.

[Clinical study of invasive fungal infection secondary to systemic lupus erythematosus].

OBJECTIVE: To study the clinical characteristics of invasive fungal infection secondary to systemic lupus erythematosus (SLE). METHODS: We observed the clinical features and experimental examination in 91 patients treated in Xiangya Hospital in recent years, of which 48 patients with invasive fungal infection and 41 patients without invasive fungal infection. RESULTS: The invasive fungal infection secondary to SLE mainly occurred in the lungs, nervous system, and urinary system. The fungi were mainly Candida albins and Aspergillus. The rate of invasive fungal infection in SLE patients and the level of CRP and TNF-α in these patients were significantly increased. The occurrence of invasive fungal infection was positively correlated with the prolonged course of disease, long-term use of immunosuppressants and antibiotics, and occurrence of complications, such as hypoproteinemia, leukocytopenia, and so on. The levels of C-reactive protein (CRP) and tumor necrosis factor-α(TNF-α) were increased in SLE patients with invasive fungal infection. CONCLUSION: The clinical features of SLE patients with invasive fungal infections are long course of disease, long-time use of immunosuppressants or antibiotics, and occurrence of complications, such as hypoproteinemia or leukopenia. The level of CRP and TNF-α can be used as an important reference index for diagnosing invasive fungal infections.

Boosting thermoelectric performance of HfSe2 monolayer by selectivity chemical adsorption.

In this work, a strategy to boosting thermoelectric (TE) performance of 2D materials is explored. We find that, appropriate chemical adsorption of atoms can effectively increase the TE performance of HfSe2 monolayer. Our results show that the adsorption of Ni atom on HfSe2 monolayer (Ni-HfSe2) can improve the optimal power factor PF and ZT at 300 K, increased by more than ∼67% and ∼340%, respectively. The PF and ZT of Ni-HfSe2 at 300 K can reach 85.06 mW m-1 K-2 and 3.09, respectively. The detailed study reveal that the adsorption of Ni atom can induce additional conductional channels of electrons, enhance the coupling of acoustic-optical phonons and the phonon anharmonicity, resulting in an obvious increment of electrical conductivity (increased by more than ∼89%) in n-type doped system and an ultralow phonon thermal conductivity (1.17 W/mK at 300 K). The high electrical conductivity and ultralow phonon thermal conductivity results in the significant increments of PF and ZT. Our study also shows that, Ni-HfSe2 is a thermal, dynamic and mechanical stable structure, which can be employed in TE application. Our research indicates that selectivity chemical adsorption is a promising way to increase TE performance of 2D materials.

The Clinical Effects of Febuxostat Alone or Combined with Arthroscopic Surgery for Gout: A Single-Center Retrospective Study.

PURPOSE: The purpose of the study was to retrospectively analyze the effects of febuxostat combined with arthroscopic debridement of monosodium urate crystal deposition and febuxostat treatment alone on uric acid levels and acute flares in gout patients. PATIENTS AND METHODS: We retrospectively analyzed gout patients who were treated from February 2016 to December 2020. Patients were divided into a control group (febuxostat treatment alone) or a combined group (febuxostat combined with arthroscopic surgery). We recorded and analyzed clinical data including age, sex, body mass index, comorbidities, lesion affected joints, acute flare times, medications history, febuxostat side effects, arthroscopic complications, and serum creatinine and uric acid levels changes. RESULTS: There were 80 patients in the control group and 93 patients in the combined group. At the beginning of treatment, the combined group had significantly higher disease severity (higher serum uric acid levels and more acute gout flare times). Arthroscopy was performed in 61 knees and 38 ankles, and 86 joints showed crystals deposition. Compared with baseline, follow-up results showed that serum creatinine significantly decreased in the combined group, and serum uric acid and acute gout flare times significantly decreased in both groups (all p < 0.05). In the comparison between the two groups at the follow-up endpoint, acute gout flare times did not differ significantly (p > 0.05), however, serum creatinine and uric acid levels were lower in the combined group compared with those in the control group (ps < 0.05). CONCLUSION: Febuxostat combined with arthroscopic debridement of monosodium urate crystal deposition or tophi had a superior effect on lowering uric acid levels and acute flare times in gout patients than did febuxostat alone.

Arg972 insulin receptor substrate-1 polymorphism and risk and severity of rheumatoid arthritis.

AIM: To explore the association between the Arg(972) insulin receptor substrate (IRS)-1 polymorphism (rs1801278) and the risk and disease activity/severity of rheumatoid arthritis (RA). METHOD: We genotyped the Arg(972) IRS-1 polymorphism in 871 pairs of age-, sex-, body mass index-, residence area- and current smoking status-matched RA patients and controls. We assessed RA severity using the disease activity score of 28 joints (DAS28). RESULTS: The AA (homozygous Arg(972) IRS-1) and GA (heterozygous Arg(972) IRS-1) genotypes were significantly associated with high risk of RA with or without adjustment for comorbidities (P < 0.001). The A allele was significantly associated with high risk of RA (P < 0.001). The AA genotype was significantly associated with high/severe RA activity (P < 0.001), while the GG genotype (wild type IRS-1) had protective effects. CONCLUSION: The Arg(972) IRS-1 polymorphism is associated with increased risk and disease activity/severity of RA, and therefore may be a potential prognostic factor for RA. This study adds novel insights into the pathogenesis of RA.

Arg972 insulin receptor substrate-1 enhances tumor necrosis factor-α-induced apoptosis in osteoblasts.

The presence of Arg972 insulin receptor substrate-1 (IRS-1) is associated with impaired insulin/IRS-1 signaling to activate phosphatidylinositol-3 kinase (PI3K). Tumor necrosis factor-α (TNF-α), an inflammatory cytokine with a central role in the pathogenesis of rheumatoid arthritis (RA), induces apoptosis in osteoblasts, which are the principal cell type responsible for bone loss in RA. In our previous study, an association between Arg972 IRS-1 and a high risk and severity of RA was identified. In the present study, the effects of Arg972 IRS-1 and IRS-1 on TNF-α-induced apoptosis in human osteoblasts were examined. Normal and RA osteoblasts were stably transfected with Arg972 IRS-1 and IRS-1. In addition, cells were stably transduced with IRS-1-shRNA to knock down IRS1. Following stimulation with 10 nM insulin for 30 min, the stable overexpression of Arg972 IRS-1 and knock down of IRS-1 significantly decreased IRS-1-associated PI3K activity and Akt activation/phosphorylation at serine 473 (ser473) and enhanced TNF-α-induced apoptosis in normal and in RA osteoblasts. By contrast, the stable overexpression of IRS-1 significantly increased the levels of IRS-1-associated PI3K activity and Akt phosphorylation (ser473) and inhibited TNF-α-induced apoptosis, which was eliminated by pretreatment with 50 µn BJM120, a selective PI3K inhibitor, for 30 min. In conclusion, the present study provided the first evidence, to the best of our knowledge, that insulin stimulation of Arg972 IRS-1 and IRS-1 enhanced and inhibited TNF-α-induced apoptosis, respectively in normal and RA osteoblasts by a PI3K­dependent mechanism. These findings suggest that insulin/IRS-1 signaling is important in the pathogenesis of RA.

[Effects of starvation and re-feeding on carbohydrate metabolism of Marsupenaeus japonicus].

This paper studied the variations of glucose concentration in haemolymph and glycogen concentration in hepatopancreas and muscle of Marsupenaeus japonicus under starvation and re-feeding. Groups C, S1, S2 and S3 were deprived of food for 0, 10, 15 and 25 days, respectively, and then re-fed for 10 days. Under starvation, the glucose concentration in haemolymph and glycogen concentration in hepatopancreas decreased rapidly at the beginning, and the glycogen concentration in muscle was the lowest after 10-day fasting. In the following 5 days, the glucose concentration in haemolymph and glycogen concentration in hepatopancreas and muscle recovered to their initial levels due to gluconeogenesis, but the glycogen concentration kept declining with fasting. After refeeding, the glycogen concentration in hepatopancreas and muscle recovered well, and the glucose concentration in haemolymph had a sharper increase in groups S1 and S2 than in group C, but was markedly less in group S3 than in group C. These results indicated that long-term starvation had a greater effect on the glucose concentration in haemolymph.