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In this paper, we investigated the potential use of a new organic-inorganic hybrid crystal structure based on KNO3 in ignition compositions. H2dabco[K(NO3)3] (DAN-2) with organic-inorganic hybrid crystal structure is synthesized through intermolecular assembly technology. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to detect the crystal morphology, structure and molecular structure of DAN-2, which has a regular cubic structure. Experimental data were obtained using thermogravimetric/differential scanning calorimetry (TG-DSC), closed bomb test and high-speed photography, which were then used to study and analyze the thermal decomposition properties and combustion properties of DAN-2. The initial thermal decomposition temperature of DAN-2 was low (194 °C) and the activation energy of the thermal decomposition was 154 kJ/mol. Possible thermal decomposition mechanisms are further discussed and proposed. This research pushed forward the application of organic-inorganic hybrid crystal structure oxidant DAN-2 in ignition system.

AIM: To compare high or low concentration of hyaluronic acid eye drops (HY) for dry eye syndromes (DES). METHODS: Randomized controlled trials (RCTs) comparing various concentrations of HY were searched in PubMed, Embase, Web of Science, Cochrane, SinoMed, CNKI, Wanfang Database, CQVIP, and Chinese journals databases between inception and July 2023. Pooled standardized mean differences (SMD) or weighted mean difference (WMD) with 95% confidence intervals (CI) from RCTs evaluating Schirmer's I test (SIT), corneal fluorescein staining score (CFS), tear breakup time (TBUT), DES score (DESS), and Ocular Surface Disease Index (OSDI) were calculated. Sensitivity analysis, Egger's test and Meta-regression analysis were performed for all indicators. RESULTS: We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria, involving 1796 cases. High-concentrations group significantly improved the outcome of CFS according to random effects modelling (SMD, -3.37; 95%CI, -5.25 to -1.48; P=0.0005). The rest of the results were not statistically significant, including indicators such as SIT, TBUT, DESS and OSDI. CONCLUSION: For dry eyes with positive corneal staining, a high concentration of HY is recommended, whereas in other cases, a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes.

Fe/N-based biomass porous carbon composite (Fe/N-pCarbon) was prepared by a facile high-temperature carbonization method from biomass, and the effect of Fe/N-pCarbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was studied. Biomass porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N precursors. Fe/N-pCarbon was prepared simply by the high-temperature carbonization method. It was found that it showed the inherent catalysis properties for thermal decomposition of DAP-4. The heat release of DAP-4/Fe/N-pCarbon by DSC curves tested had increased slightly, compared from DAP-4/Fe/N-pCarbon-0. The decomposition temperature peak of DAP-4 at the presence of Fe/N-pCarbon had reduced by 79°C from 384.4°C (pure DAP-4) to 305.4°C (DAP-4/Fe/N-pCarbon-3). The apparent activation energy of DAP-4 thermal decomposition also had decreased by 29.1 J/mol. The possible catalytic decomposition mechanism of DAP-4 with Fe/N-pCarbon was proposed.

Objective To explore correlations between body mass index (BMI), preoperative systemic immune-inflammation index (SII) and endocrine therapy resistance, and evaluate BMI and SII as predictors of resistance, in patients with luminal breast cancer. Methods This retrospective study included patients with luminal breast cancer who underwent endocrine therapy at Hebei General Hospital. Relationships between BMI and SII subgroups, and clinicopathological parameters were analysed using χ 2 -tests. Disease-free survival was assessed using Log-rank statistics. Multivariate analysis of factors related to disease progression were analysed using Cox proportional hazards model. Results Out of 161 patients, those with normal BMI and low SII had significantly lower endocrine resistance rates versus those with high BMI and SII, and BMI was significantly positively correlated with SII. High BMI or SII was associated with significantly lower disease-free survival rates. Hazard ratios for disease progression risk were 6.036, 3.508 and 1.733, for SII, BMI and TNM stage, respectively. Conclusion In patients with luminal breast cancer, high BMI (>23 kg/m 2 ) and SII (>518 × 10 9 /L) levels may predict high endocrine resistance rates. BMI, SII and TNM stage were independent prognostic factors for endocrine therapy resistance.

AIM: To investigate the curative effect of phacoemulsification and intraocular lens(IOL)implantation combined with goniosynechialysis in the treatment of age-related cataract merging with primary angle-closure glaucoma(PACG).METHODS: Totally 80 patients with age-related cataract merging with PACG were in our hospital from January 2014 to January 2016. The preoperative average intraocular pressure(IOP)was 33.22±3.17mmHg; the average depth of anterior chamber was 2.07±0.15mm; the dynamic situation of primary angle closure ≤1/2 cycle by gonioscope. They were randomly divided into Group A and B for doing a study. All the two groups were treated with phacoemulsification and intraocular lens implantation. And the Group A was with goniosynechialysis. The following up period was 2mo, and we observed the IOP, chamber depth and the anterior chamber angle.RESULTS: The change of chamber depth and intraocular pressure about the two groups: the average intraocular pressure of the Group A was 15.11±3.67mmHg,the chamber depth was 3.11±0.08mm; those of the Group B were 17.24±1.67mmHg, 2.76±0.15mm respectively; the differences had statistical significance(PPCONCLUSION: The phacoemulsification and intraocular lens implantation combined with goniosynechialysis in the treatment of age-related cataract merging with primary angle-dosure glaucoma is safe and reliable. It's simple to operate, and do not increase the risk of surgery.

In the title complex, {[Zn(NCS)2(C15H15N9)2]·H2O}n, the ZnII ion is located on an inversion centre and is six-coordinated in a distorted octahedral geometry, coordinated by N atoms from four bridging 1,3,5-tris(1,2,4-triazol-1-ylmethyl)benzene (ttmb) ligands and two terminal SCN− counter-anions. Two of the three triazol groups in each ttmb ligand link the ZnII atoms, forming a looped-chain structure along [0-11]. The lattice water molecule shows half-occupancy due to disorder around an inversion centre.

In the title molecule, C16H19BrO3, all non-H atoms apart from the Br atom are approximately coplanar, with a maximum deviation of 0.242 (4) Å. The C—C—C—Br torsion angle is 66.5 (4)°.

BACKGROUND: Preterm birth, the birth of an infant prior to 37 completed weeks of gestation, is the leading cause of perinatal morbidity and mortality. Preterm infants are at greater risk of respiratory, gastrointestinal and neurological diseases. Despite significant research in developed countries, little is known about the causes of preterm birth in many developing countries, especially China. This study investigates the association between sciodemographic data, obstetric risk factor, and preterm birth in five Maternal and Child Health hospitals in Beijing, China. METHODS AND FINDINGS: A case-control study was conducted on 1391 women with preterm birth (case group) and 1391 women with term delivery (control group), who were interviewed within 48 hours of delivery. Sixteen potential factors were investigated and statistical analysis was performed by univariate analysis and logistic regression analysis. Univariate analysis showed that 14 of the 16 factors were associated with preterm birth. Inter-pregnancy interval and inherited diseases were not risk factors. Logistic regression analysis showed that obesity (odds ratio (OR) = 3.030, 95% confidence interval (CI) 1.166-7.869), stressful life events (OR = 5.535, 95%CI 2.315-13.231), sexual activity (OR = 1.674, 95%CI 1.279-2.191), placenta previa (OR 13.577, 95%CI 2.563-71.912), gestational diabetes mellitus (OR = 3.441, 95%CI1.694-6.991), hypertensive disorder complicating pregnancy (OR = 6.034, 95%CI = 3.401-10.704), history of preterm birth (OR = 20.888, 95%CI 2.519-173.218) and reproductive abnormalities (OR = 3.049, 95%CI 1.010-9.206) were independent risk factors. Women who lived in towns and cities (OR = 0.603, 95%CI 0.430-0.846), had a balanced diet (OR = 0.533, 95%CI 0.421-0.675) and had a record of prenatal care (OR = 0.261, 95%CI 0.134-0.510) were less likely to have preterm birth. CONCLUSIONS: Obesity, stressful life events, sexual activity, placenta previa, gestational diabetes mellitus, hypertensive disorder complicating pregnancy, history of preterm birth and reproductive abnormalities are independent risk factors to preterm birth. Identification of remedial factors may inform local health and education policy.

Hafnium content and its change are of significance in geochemistry and cosmochemistry; however, the determination of hafnium has always been problematic in analytical chemistry. In this paper, a new idea is proposed for the determination of hafnium in geochemical samples, including rocks, soils, and stream sediments. Through the comparison of two conventional open-type acid digestion methods (HF-HNO3-HClO4 and HF-HNO3-H2SO4), it was found that although neither of these methods could fully digest the zirconium and hafnium in a sample, the zirconium and hafnium digestion behaviors in one sample were consistent in the 60 experimental geochemical reference materials with different properties, so the experimentally determined Zr/Hf ratio in solution could be used to calculate the hafnium content in a sample. In addition, possible mass spectral interferences during the determination of zirconium and hafnium by high resolution inductively coupled plasma mass spectrometry (HR-ICPMS) were studied, and it was found that the mass spectral interferences of the selected isotopes 90Zr and 178Hf could be neglected. The mass spectral behaviors of 90Zr and 178Hf were also very consistent during the determination by HR-ICPMS. Since the hafnium content was calculated using the ratio value, all of the errors (including the errors in weighing process, the accidental errors during operation and the instrument fluctuation in the determination) of the Zr/Hf ratio could be effectively reduced or even eliminated. The relative standard deviation of the actual samples was lower than 3.2%, and the detection limit of the method (considering the dilution effect and matrix effect during measurement of the Zr/Hf ratio and zirconium content) was 0.04 μg/g. The proposed method could satisfy the requirement for the determination of hafnium in geochemical samples. [ABSTRACT FROM AUTHOR]

A hybrid method, combining analytic Kirchhoff approximation (KA) and numerical method of moments (MoMs), is developed to solve the two-dimensional (2D) scattering problem of a dielectric target with arbitrary cross section above a moderate perfect electric conductor (PEC) rough surface under TE-polarized tapered wave incidence. The induced current on the rough surface is analytically expressed using the KA method, which depends on the tapered incident wave and the field illuminating by current distribution on the target, leaving only unknown induced current on the target. So the electric field integral equations of the induced currents on the target only can be derived; it allows a substantial reduction of computation time and memory requirement. Furthermore, for different secondary scattering of the underlying rough surface, different truncations of the rough surface are taken to speed up computation of the scattering contribution from the rough surface to the target. Making use of Monte Carlo realization, bistatic scattering from a cylindrical target above a PEC rough surface is well simulated to test validity and efficiency of the proposed method. Numerical results from the hybrid method have good agreements with those from the conventional method of moments. However, the computational time and the memory requirements have been greatly reduced. [ABSTRACT FROM AUTHOR]