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This study describes a rare case of male granulomatous lobular mastitis (GLM) with recurrence in different sites on the ipsilateral side. A 48-year-old male patient presented with no previous history of breast-related disease, and physical examination suggested a mass in the right breast. Ultrasonography revealed a cyst and infection in the right breast. No obvious abnormality was found in laboratory analysis, and a core needle biopsy revealed GLM. Incision and drainage were applied to the right lesion, and symptoms resolved within a few weeks. At 2 years following this initial presentation, the patient reported that the right breast mass reappeared in different locations after the consumption of alcohol. Relevant examination and a core needle biopsy again suggested GLM of the right breast. The patient declined hormone therapy and was subsequently lost to follow-up. After reviewing this case, the course of the disease in this patient, and the connection between gynecomastia and GLM, along with ipsilateral recurrence, are under investigation.

To effectively monitor and control the severe mining-induced rockburst in deep fault area, the fault activation law and the mechanical essence of rockburst induced by crossing fault mining were studied through theoretical analysis, microseismic monitoring, field investigation, and other methods; numerical simulation was employed to verify the obtained fault activation law and the mechanical nature. First, the distribution of microseismic sources at different mining locations and the fault activation degree were analyzed. According to the microseismic frequency and the characteristics of the energy stage, the fault activation degree was divided into three stages: fault stress transfer, fault pillar stress behavior, and fault structure activation. It was determined that the impact disaster risk was the strongest in the stage of the fault pillar stress behavior. Based on the periodic appearance law of microseisms in fault area, three types of conceptual models of fault-type rockburst were proposed, and the rockburst carrier system model of “roof-coal seam-floor” in the fault area was established. The mechanical essence of fault-type rockburst was obtained as follows: under the action of fault structure, the static load of the fault coal pillar was increased and superimposed with the active dynamic load of the fault, leading to high-strength impact disaster. Finally, the prevention and treatment concepts of fault-type rockburst were proposed. The monitoring and prevention measures of fault-type rockburst were taken from two aspects: the monitoring and characterization of fault rockburst and weakening control of the high static load of the fault coal pillar and dynamic load of fault activation. The proposed concepts and technical measures have been verified in the working face 14310 of Dongtan Coal Mine with sound results. The research results have a guiding significance for the prevention and control of rockburst in a similar mining face under crossing fault mining.

In the past, the construction of high-speed railway stations was mostly concentrated in cities, rarely in cultural reserve area, and the degree of humanistic environmental protection was low. In addition, most of the high-speed railways entered into the city with ground lines, which had adverse effects on the urban environment. In this paper, the advantages and disadvantages of the current high-speed railway station construction concepts at home and abroad were analyzed. The design concept and method of the new generation of high-speed railway station and tunnel projects, included environmental integration, safety and comfort, low-carbon environmental protection, etc., were proposed based on the Beijing-Zhangjiakou High-speed Railway station and tunnel projects, especially Tsinghua Park shield tunnel with the theme of intelligent construction and underground Badaling Great Wall Station with the theme of cultural protection. Environmental integration includes station scene integration in scenic spots and tunnel-city integration in high-speed railway processes; safety and comfort concept include the safety of the station and tunnel engineering structure and the comfort of the operating environment; Low-carbon environmental protection includes BIM-based environmental protection and efficient whole-process management concepts, as well as green and low-carbon construction and operation concepts. [ABSTRACT FROM AUTHOR]

In modern diesel engines, the exhaust soot primarily comes from the main-injection combustion and post-injection combustion. Therefore, to reduce the diesel soot emissions, it is essential to better understand the soots generated from the main-injection combustion (main-soot) and from the post-injection combustion (post-soot). This work focused on the properties of the main-soot and post-soot during the combustion process, including the primary particle size, nanostructure and soot mass. The in-cylinder soot samples were obtained using a self-developed total cylinder sampling system, and the primary particle size and nanostructure were determined using high-resolution transmission electron microscopy. The isolation of the post-soot was achieved by adding dimethyl ether to the intake gas instead of the real main-injection to create a simulated main-injection combustion environment for post-soot formation. Combustion analysis and numerical simulation results showed that the simulated combustion environment for post-soot formation generated by the DME combustion was very similar to that generated by the real main-injection combustion. During the combustion process, although the main-soot and post-soot exhibit similar variations in the primary particle size, the maximum primary particle size of the post-soot is smaller than that of the main-soot (23.38 nm for the main-soot and 20.51 nm for the post-soot). The main-soot and post-soot show almost the same trends in the nanostructure, as characterized by the fringe length, separation and tortuosity, throughout the combustion process. The introduction of the post-injection accelerates the reduction of the primary particle size of the main-soot and the increase in the structural order of the main-soot. Because a large number of the main-soot particles are oxidized during the post-injection combustion, the post-soot accounts for a considerable proportion in the engine-out soot (i.e., 42%). [ABSTRACT FROM AUTHOR]

In this work, the role of volatile organic compounds (VOCs) in soot oxidation and fragmentation was investigated in a lean, premixed CH 4 flame. An aerosol generator was used to homogeneously disperse soot with and without VOCs (termed Soot-W and Soot-WO, respectively) into the flame. Because minimal soot was formed in the flame itself, information on the fragmentation of the Soot-W and Soot-WO during the oxidation process was readily captured to determine the role of VOCs in soot fragmentation. The integrated number concentration of fine mode particles and the degree of particle aggregation show that the presence of VOCs suppresses soot aggregate fragmentation, primarily by the mitigating consumption of the neck sites between primary particles due to the decreased specific surface area. The actual oxygen diffusion route and effective pore width between the crystallite structures were determined using the image analysis technique. To determine the characteristic regime of oxygen diffusion, the distribution of effective pore width was studied using high-resolution transmission electron microscopy and image analysis. The estimated effectiveness factor indicates that the presence of VOCs lowers the propensity of internal burning via intra-particle oxygen diffusion, and reduces the extent of primary particle fragmentation, as evidenced by a relatively smaller peak of ultrafine particles. The analysis of the nanostructure of neck sites vs. the bulk discovers significantly more disordered and thus reactive structure at neck sites, explaining the prevalence of aggregate fragmentation over primary particle fragmentation. The finding of the role of VOCs in oxidation-driven fragmentation is beneficial to the optimization of existing models for predicting the number concentration of fine and ultrafine particles. Furthermore, a better understanding of this role may aid in the control of the most harmful fine and ultrafine particle emissions. [ABSTRACT FROM AUTHOR]

In order to explore the freezing damage mechanism in the tunnel in cold region, the temperature field distribution law and calculation method are proposed based on the long-term measured data and numerical simulation experiments with reference to the 10 tunnels along the Jilin-Tumen- Hunchun High-speed Railway. Research results show that the air temperature field in the tunnel can be fitted and calculated by means of parabola of second order. The main control parameters include tunnel length, tunnel opening temperature growth gradient, tunnel opening temperature growth and average wind speed in the tunnel; the tunnel lining structure has good short wave filtering characteristics, which can filter out the daily temperature fluctuation of the lining surface; the temperature behind the tunnel lining is basically the same as the 5-day average temperature curve of the lining surface, based on which, the length of the tunnel reinforced concrete lining can be determined; the average difference between the second lining wall temperature and the initial support second lining contact surface temperature is 2.2 °C without insulation layer; when the temperature of the secondary lining wall in the tunnel is lower than -2.2 °C, thermal insulation layer needs to be set up; with insulation layer, the average difference between the temperature of the second lining wall and that of the contact surface of the initial support and the second lining is 10 °; when the temperature of the secondary lining wall in the tunnel is lower than -10 °C, the effect of the thermal insulation layer can hardly meet the requirement of tunnel cold proof, and alternative thermal insulation measures are required. [ABSTRACT FROM AUTHOR]