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Objective: To compare the efficacy and safety of combining diosmin with Jiuhua hemorrhoid suppository versus diosmin alone for the treatment of hemorrhoid hemorrhage. Method: The Jiuhua hemorrhoid suppository study was conducted in 10 medical centers across China from April 1, 2019 to June 30, 2020. Patients with hemorrhoid bleeding were randomized in a ratio of 1 : 1 to either receive Jiuhua hemorrhoid suppository and diosmin tablets (the study group) or diosmin tablets alone (the control group). The suppository was used once a day after defecation or at bedtime after rinsing the anus with warm water. Diosmin tablets were administered only once a day (0.9 g). The primary endpoint of the study was the assessment of hemorrhoid bleeding relief 7 ± 2 days after treatment, classified as “very effective” “effective” and “ineffective”. The secondary endpoint included the evaluation of pain alleviation using the visual analogue scale (VAS, with scores ranging from 0 to 10) and edema (with scores ranging from 0 to 3). The safety of the two treatment regimens was evaluated 14 ± 2 days after drug administration. Results: The full analysis set (FAS) comprised 107 participants in the study group and 111 in the control group, while the per-protocol set (PPS) included 106 participants in the study group and 111 in the control group. In terms of hemorrhoid bleeding, the proportion of very effective and effective cases in the study group were significantly higher than that in the control group [106 (99.06 %) vs. 91 (81.98 %), P < 0.0001] in the FAS, and the PPS results [105 (99.06 %) vs. 91 (81.98 %), P < 0.0001] were comparable to the FAS results. The pain VAS scores at day 7 after treatment were comparable between the two groups (0.80 ± 1.17 vs. 0.80 ± 1.20, P = 0.2177). The majority of the participants in both groups had an edema score of 0 at day 7 after treatment [96 (89.72 %) vs. 99 (91.67 %), P = 0.3705]. Adverse events (AEs) occurred in 9 patients (8.4 %) in the study group and 3 patients (2.7 %) in the control group. In addition, 5 AEs in the study group and 1 AE in the control group were possibly in association with the study drug. Conclusion: Compared with the administration of diosmin oral tablets alone, the addition of Jiuhua hemorrhoid suppository to the tablets demonstrates enhanced efficacy in addressing hemorrhoid bleeding, with satisfactory patient adherence and acceptable safety.

With increasing environmental pollution from ship exhaust emissions and increasingly stringent International Maritime Organization carbon regulations, there is a growing demand for cleaner and lower-carbon fuels and near-zero-emission marine engines worldwide. Liquefied natural gas is a low-carbon fuel, and when liquefied natural gas (LNG) is used on ships, dual-fuel methods are often used. The pre-chamber plays a key role in the working process of dual-fuel engines. In this paper, an effective three-dimensional simulation model based on the actual operating conditions and structural characteristics of a marine low-pressure dual-fuel engine is established. In addition, the effects of changing the Precombustion chamber (PCC) volume ratio and the PCC orifice diameter ratio on the mixture composition, engine combustion performance, and pollutant generation were thoroughly investigated. It was found that a small PPC volume ratio resulted in a higher flame jet velocity, a shorter stagnation period, and an acceleration of the combustion process in the main combustion chamber. When the PCC volume was large, the Nitrogen oxygen (NOx) ratio emission was elevated. Moreover, the angle of the PCC orifice affected the flame propagation direction of the pilot fuel. Optimizing the angle of the PCC orifice can improve combustion efficiency and reduce the generation of NOx. Furthermore, reasonable arrangement of the PCC structure can improve the stability of ignition performance and accelerate the flame jet velocity. [ABSTRACT FROM AUTHOR]

Maritime shipping is a key component of the global economy, representing 80–90% of international trade. To deal with the energy crisis and marine environmental pollution, hydrogen-natural gas-diesel tri-fuel engines have become an attractive option for use in the maritime industry. In this study, numerical simulations and experimental tests were used to evaluate the effects of different hydrogen ratios on the combustion and emissions from these engines. The results show that, in terms of combustion performance, as the hydrogen proportion increases, the combustion ignition delay time in the cylinder decreases and the laminar flame speed increases. The pressure and temperature in the cylinder increase and the temperature field distribution expands more rapidly with a higher hydrogen ratio. This means that the tri-fuel engine (H2+CH4+Diesel) has a faster response and better power performance than the dual-fuel engine (CH4+Diesel). In terms of emission performance, as the hydrogen proportion increases, the NO emissions increase, and CO and CO2 emissions decrease. If factors such as methane escape into the atmosphere from the engine are considered, the contribution of marine tri-fuel engines to reducing ship exhaust emissions will be even more significant. Therefore, this study shows that marine hydrogen-natural gas-diesel tri-fuel engines have significant application and research prospects.

In China, the total area of rocky desertification covers 1.01x107 hm², accounting for 22.3% of the karst area. Nowadays, rocky desertification has become one of the three major land degradation problems in our country, which has seriously affected our economic development and environmental governance. Naturally, rock weathering in the karst area is so long that it takes from a few decades to a hundred years to form a centimeter think of red soil. Because the karst area is rich in calcium and barren in soil, ecological restoration of this area is urgent in both rocky desertification control and karst carbon sink. Carbonic Anhydrase (CA), one of the fastest catalyzing enzymes, can promote the weathering of carbonate rocks by accelerating the hydration reaction of CO2, thus providing soil matrices for plant colonization. At the same time, CA can also be used to absorb CO2 in the atmosphere to fix the carbon source, thereby participating in the carbon cycle process of karst dynamic system. The CA-producing microorganisms are considered to have good application prospects in the restoration of degraded karst habitats. However, for the target strains isolated from favorable habitat, their weak adaptability to the extreme environment may constrain them from exerting their expected effects. In order to select the strain with high CA activity in the extremely degraded karst habitat, CA-producing strains were isolated from the samples of severely degraded rocky karst habitats in this study. The study area is located in Hechi City, Guangxi Zhuang (23°41'--25°37' N, 106°34'-109°09' E). It has a subtropical monsoon climate, with an average annual temperature of 16.9-21.5 °C. The area is typically developed with karst, scattered with thin soil and highly exposed with rocks. From September to October 2021, four different habitat samples were collected, including lichen in the area with extreme rocky desertification weathered materials under moss, soil under moss, and weathered materials under moss in karst native forest. The source of isolation was a mixture of the four different habitat samples, 1g of each. CA-producing strains were isolated and screened from karst rocky habitats by inoculating suspension of isolation source in calcium carbonate medium with a sprayer. The field emission scanning electron microscope was used for morphological identification of the strain. The physiological and biochemical characteristics of the strain were confirmed by carbohydrate decomposition test, V-P test, methyl red test, citrate utilization test, nitrate reduction test, starch hydrolysis test and contact enzyme test. Strains were identified by 16S rRNA sequence analysis. The CA activity of single strain and mixed strain was determined by electrode method. The sequence alignment was performed in the National Center for Biotechnology Information Database. In MEGA6, Neighbor-Joining method is used to construct the phylogenetic tree. SPSS software was used to analyze whether there were significant differences in CA activity among different strains/microflora. The results show that six CA-producing strains were isolated by calcium carbonate medium, namely, Flavobacterium resistens, Delftia acidovorans, Stenotrophomonas rhizophila, Pseudomonas oleovorans, Agrobacterium cavarae and Bacillus albus. The CA activity of Stenotrophomonas rhizophila was the highest, up to 4.27 U½mL-1½OD600-1, while that of Bacillus albus was only 0.46 U½mL-1½OD600-1, which indicated that although CA commonly existed in prokaryotes, the activity of different species of bacteria varied greatly. Mixed culturing of Stenotrophomonas rhizophila whose CA activity is high with other strains led to a decrease in CA activity, indicating the great potential application of Stenotrophomonas rhizophila in the extremely oligotrophic environment. The results provide a new bacterial source for ecological restoration of extremely degraded karst habitats. However, all the CA activity decreased when the isolated Stenotrophomonas rhizophila strain N6 with high CA activity is mixed with other 5 strains. Because of the complex living environment, the competition of indigenous microbial community will reduce the survival efficiency of the added microorganisms, make it difficult to form a stable community structure, and then reduce the repair effect. In restoration of degraded karst habitat, whether there is a kind of dominant bacteria that is symbiotic with Stenotrophomonas rhizophila N6 to jointly promote carbonate dissolution is a research focus. Therefore, future studies should identify the core species that drive the restoration of degraded habitats, and explore the relationship between the isolated and culturable CA dominant bacteria and the core species. These study focuses will promote the research and development of biological fertilizer for the rapid restoration of degraded karst habitats. [ABSTRACT FROM AUTHOR]

An adaptive control strategy for fuel cell stabilization is proposed to alleviate the coupling effects of power output variation and performance degradation in the whole service life. An improved semi-empirical model is firstly developed to describe and analyze the direct methanol fuel cell (DMFC) performance under different operating conditions while considering degradations. Multi-objective optimizations are then utilized for the adaptive generation of control strategy to stabilize the voltage. Experiments are implemented to validate the effectiveness of the adaptive control strategy at different time periods during long-term operation. The results show that the improved semi-empirical model can provide a dynamic description of DMFC I-V relationships with the time. The adaptive control strategy developed from this model is effective for voltage stabilization that the deviation could be constrained in ±10% at different power outputs during long-term operation. [ABSTRACT FROM AUTHOR]