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Echocardiographic guidance in left atrial appendage (LAA) closure procedures is increasingly recognized for its potential to enhance patient outcomes in atrial fibrillation (AF). This retrospective study assesses its impact on hospital stay duration, readmission rates and surgical site wound complications in 200 AF patients. Divided equally into an echocardiographically guided group (Group E) and a non‐guided group (Group N), the analysis focused on detailed patient data encompassing hospital stay, 30‐day readmission and wound complications. Findings revealed that Group E experienced a significantly shorter average hospital stay of 3.5 days, compared with 6.5 days in Group N, along with a lower 30‐day readmission rate (5% vs. 18% in Group N). Furthermore, Group E showed a considerable reduction in surgical site wound complications, such as infections and hematomas. The study concludes that echocardiographic guidance in LAA closure procedures markedly improves postoperative wound outcomes, underscoring its potential as a standard practice in cardiac surgeries for AF patients. This approach not only optimizes patient safety and postoperative recovery but also enhances healthcare resource utilization. [ABSTRACT FROM AUTHOR]

Backfilling material specimens were prepared with Pb-bearing ore tailings and a blast furnace slag-steel slag based cementing agent(BSCA) used as a replacement for cement in traditional backfilling materials. Other types of specimens with ordinary Portland cement(P·I 42.5) as cementing agents were also made for comparison. Flowability and compressive strength tests were performed to study the working performance of the specimens,and leaching tests were done to investigate the immobilization of Pb2+ in the specimens. The phase composition of the hydrated specimens was analyzed by means of X-ray diffraction,Fourier transform infrared spectroscopy and differential scanning calorimetry. It is found that the backfilling material with BSCA has a flowability of 50 mm higher than that with ordinary cement. The 28-d compressive strength of the BSCA-based specimens reaches 3.0 MPa,which meets the strength requirement for underground backfilling. The quantities of Pb2+ leached from the BSCA-based specimens aged for 28 d are below 0.05 mg·L-1,which is the threshold value of Pb2+ concentration for Type Ⅲ ground water in Chinese quality standard for ground water GB/T 14848-93. In comparison,the quantities of Pb2+ leached from the cement-containing specimens aged for 28 d are 0.1 mg·L-1. The reason for this higher immobilization degree of Pb2+ in the hydrated BSCA-based specimens is that a higher amount of ettringite forms in them. Moreover,the formation of zeolite-like facies in the hydrated BSCA-based specimens is favorable for immobilizing Pb2+.

The substitution of iron ore tailing powders(IP) for fly ash as mineral admixtures was studied in the development of engineered cementitious composites(ECC). The focus was placed on the effect of IP content on the tensile properties and compressive strength of ECC. The mechanical properties of ECC with IP were also compared with those of traditional ECC with fly ash. Experimental results show that it is feasible to use IP as mineral admixtures to produce high-ductile ECC. ECC with IP exhibits a lower strength performance but a higher ductility under tensile load than ECC with fly ash at the same addition of mineral admixtures. ECC with an IP/cement mass ratio of 1. 2-2. 2 shows a 28-d compressive strength of 36. 7-54. 2 MPa,which meets the compressive strength requirement of normal concrete structures,and a 28-d tensile ductility of 3. 4%-4. 3%. The amount of iron ore tailings in those mixtures accounts for 66. 6%-77. 0% of the total solid matrix ingredients of ECC.

The recovery of iron-bearing silicate minerals is a key on the re-separation middlings of Anshan type lean magnetite,but this recovery process should be conducted selectively. The iron grade of stage 1 tailing is only 3.92%,so there is no need to recover it. However,the iron grade of stage 2 tailing is 34.51%,thus this tailing can be returned to the mixing process before direct reduction and its iron is indirectly recovered. Under the condition of the direct reduction temperature of 1150℃,the direct reduction time of 45 min,the limestone dosage of 16% and the coal dosage of 12%,the optimum TFe and εFe obtained from closed-circuit experiment is 92.69% and 91.17%. Iron and silicon in the iron-bearing silicate are reduced to elemental iron and reengineered to aedelforsite,respectively.

A new cementing agent, RSGC, designed for filling was prepared with red mud, blast furnace slag, flue gas desulphurization gypsum and a little cement clinker. The adaptability of RSGC used in different mines was studied and the early hydration including microstructure and structural changes of silicates and aluminates were investigated by scanning electron microscopy and nuclear magnetic resonance techniques. It is found that RSGC applies not only to iron ore mines but also to copper mines, gold mines and lead——zinc mines which generally adopt the filling mining method. Filling materials used RSGC exhibit significant strength and water retention advantages over traditional cement filling materials. The RSGC paste hardens at 2.5 h. Ettringite generated before 2.5 h makes important contributions to the setting and hardening. After 4 h, parts of the tetrahedrally-coordinated aluminium turn into an octahedrally-coordinated state, and polymerization of silicates increases. This phenomenon means that ettringite, C——S——H gels and zeolites generate continuously. The combination of these hydration products in various sizes and shapes forms a compact arrangement and a dense structure, which is probably the reason why the RSGC paste obtains strength from 4 h and the strength increases dramatically from that time.

Hydration reactions of samples made from skarn-type copper tailings, blast furnace slag, quartz sand, cement clinker and natural gypsum during the process of pre-curing, autoclaving and re-curing were investigated by strength testing, X-ray diffraction analysis and scanning electron microscopy. The influences of calcium and silicon contents on the amount and variety of hydration products generated in the reactions were analyzed and the effects of hydration products on the strength of the samples were discussed. It is found that the strength of autoclaved products in different curing stages depends on the amount and variety of hydration products generated in the curing process, while the amount and variety of them hinge on the amount and existence form of calcium and silicon.

Solar photocatalysis has been an efficient option to eliminate indoor volatile organic pollutants (VOCs) due to its relatively low cost. Moreover, solar ventilation wall is a common heating and ventilating technology that supplies air circulation in a room and expels polluted air under the action of wind pressure. An efficient air purification type ventilation wall that meets indoor pollutant purification, natural ventilation and thermal fully driven by the combination of solar photocatalytic purification technology and natural ventilation wall has been developed by previous research. The aim of this updated review is to explore the development of the solar photocatalytic ventilation wall (SPVW) system and critically analyze the scientific literature on photocatalysts, models, mechanism, parameter analysis and evaluation of this multifunctional system. The review also included the effects of parameters such as initial concentrations of pollutants, ultraviolet (UV) light intensity, relative humidity, channel width, channel height on the solar photocatalytic characteristics and natural ventilation performance, and a brief performance evaluation on natural ventilation, indoor heating and solar photocatalytic degradation. The governing analysis reveals that the daily stability of the SPVW system could be achieved by enhancing the activity of the photocatalyst and decreasing fluctuation of light source in the external input. [ABSTRACT FROM AUTHOR]