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Viscosity-reducer foam flooding combines the advantages of emulsification of viscosity-reducers and selective blocking of foam to further enhance oil recovery in deep low-permeability heavy oil reservoirs during the later development stages. The suitable concentration of viscosity-reducing foam agents were selected according to the viscosity-reducing effect， foaming performance and foam stability of the agents by laboratory experiments. Meanwhile， the characteristics and recovery effects of viscosity-reducer foam flooding under different displacement modes were compared by single-core displacement experiments， and the diverting capacity of viscosity-reducing foam at various permeability ratios were investigated by parallel core experiments， and thus the enhanced oil recovery （EOR） mechanisms of viscosity-reducer foam flooding ware defined. The results demonstrate that the viscosity-reducing agents facilitate the emulsification and viscosity reduction of heavy oil， while the foams block large pore throat and inhibit N2 channeling during viscosity-reducer foam flooding. Combination of the both can improve the sweep coefficient and displacement efficiency， increase displacement pressure differential， and lower the water cut. Furthermore， the viscosity-reducer foam flooding can enhance the oil recovery by an additional 13% based on the viscosity-reducer flooding. In heterogeneous conditions， viscosity-reducer foam flooding decreases the high-permeability core channeling to direct the flow towards low-permeability cores， thereby exerting an emulsification and viscosity-reducing effect. Finally， this expands the swept volume and simultaneously enhances the displacement efficiency. While the viscosity-reduce foam flooding significantly enhance the oil recovery of deep low-permeability heavy oil reservoirs by optimizing the oil flow distribution， enhancing emulsification， and reducing heavy oil viscosity， thus providing an effective strategy for efficient development of deep heavy oil reservoirs.

Straw returning has gradually been adopted as an effective approach to address the serious degradation of farmland. However, the carbon/nitrogen (C/N) ratio of rice straw is generally too high for microorganisms to decompose the organic materials and release nutrients, which may minimize the benefits of straw returning to the agricultural production system. This study aimed to investigate the effects of straw returning on rice production and propose optimum nitrogen (N) management for early rice production under a straw returning system. The total N fertilizer that was evaluated was 165 kg N ha-1, urea (46% N), applied in different proportions in three stages of rice cultivation: basal, tillering, and panicle. Using no straw returning with the N fertilizer ratio of basal:tillering:panicle = 5:2:3 treatment (T1) as the control, four different N fertilizer ratios of basal:tillering:panicle, including 5:2:3 (T2), 5:2:2 (T3), 5:4:1 (T4), and 5:5:0 (T5) were set under straw returning. The return of straw decreased the available N in the soil at the tillering stage, and impeded root growth and the crop canopy from establishing, which decreased the effective panicles by 10.1% compared with that of T1, limiting the increases in rice grain yield. Increasing the N fertilizer ratio 10–20% (T3 and T4) at the tillering stage effectively increased the content of soil ammonium and nitrate nitrogen, improved the root growth, and increased the root activities by 16.0–40.5% at the tillering stage. As a result, the effective panicle number increased by 5.1–16.2%. Among these, T4 treatment maximized the benefits of straw returning the most. Additionally, increasing the N fertilizer ratio at the tillering stage increased the shoot uptake across the early rice growing season and synchronized crop N uptake with the accumulation of carbon assimilates, which enhanced the crop growth rate and increased the rice yield by 13.5–25.1%. It is concluded that increasing the N fertilizer ratio by 20% at the tillering stage is a promising strategy to increase the availability of N in the phases of high demand for this nutrient. [ABSTRACT FROM AUTHOR]

Background: In Asia, axillary hyperhidrosis is a frequent problem for many people, and the consequent excessive sweating can seriously affect many aspects of daily life and even lead to mental disorders. Microwave therapy is a new, non‐invasive treatment method for axillary hyperhidrosis, whose energy and long‐term effectiveness still needs to be clinically validated. Objective: The aim of this study was to evaluate the clinical efficacy, safety, histological changes, and psychological status of microwave devices in the treatment of axillary hyperhidrosis and osmidrosis. Method: We conducted a prospective self‐controlled study in a top‐tier Chinese hospital. After a 5/5 energy treatment session, a skin biopsy was taken to observe histological changes both before and after treatment. An iodine starch test was used to determine the sweating range. We evaluated symptoms of improved efficacy using the Hyperhidrosis Disease Severity Scale (HDSS) and assessed changes in life status with the DLQI. In the case of concurrent underarm odor, odor‐5, VAS, and Young‐Jin Park grading were used to assess odor relief. The effect of odor on psychology was assessed by using a psychological status symptom checklist (scl‐90). The study period was 1 year. Results: We observed 20 patients in this study. Of those, 90% met the primary treatment endpoint of a decrease in axillary hyperhidrosis symptomatology to below grade 2 on the HDSS score (p < 0.001). Furthermore, 75% of patients achieved a treatment endpoint of at least 50% reduction in VAS (p < 0.001). 70% of patients achieved a treatment endpoint of at least 50% reduction in odor‐5 (p < 0.001). The iodine starch test showed that the region decreased 99% from the baseline to 12 months after follow‐up had ended (p < 0.001). Eight patients volunteered to undergo histological examination; their average light density of immunohistochemistry decreased from 1.04 (0.4–2.11) to 0.07 (0.04–0.46; p < 0.05). The immunohistochemical positive number for sweat glands was initially 104 (59.75–132.5) but was 41.5 (29.75–62) after the procedure. None of the patients experienced any serious adverse reactions. Conclusion: The treatment demonstrated high effectiveness, safety, and short‐lived adverse reactions. [ABSTRACT FROM AUTHOR]