Role of ultrasound in diagnosing gravid uterine incarceration.

OBJECTIVE: To summarize the ultrasound characteristics, diagnostic experiences, and pregnancy outcomes of gravid uterine incarceration. METHODS: A retrospective analysis was conducted on the data of pregnant women diagnosed with gravid uterine incarceration by prenatal ultrasound at the Ultrasound Department of the Third Affiliated Hospital of Zhengzhou University from January 2020 to December 2023. Clinical data, ultrasound features, and pregnancy outcomes were analyzed. RESULTS: In this study, a total of 23 pregnant women were included. Of these, eight were diagnosed in early pregnancy, and 15 were diagnosed in mid-pregnancy. Seven participants had concurrent uterine fibroids, 10 had a history of abdominal or pelvic surgery, and two had ovarian cysts. A total of 13 cases presented with symptoms of urethral obstruction, three with rectal pressure symptoms, five cases with tight and stiff lower abdomen and two cases without special discomfort. Seventeen cases exhibited cervical compression with thinning and elongation, measuring approximately 39 to 73 mm. All 23 cases underwent manual or knee-chest positioning repositioning, with one case requiring surgical intervention. Ultimately, 22 cases resulted in full-term live births, one case experienced fetal demise at 24 weeks and one case experienced gravid uterine incarceration again in the third week after successful manual reduction, and manual reduction was performed again. CONCLUSION: Early diagnosis is critical for obstetric management and clinical prognosis, facilitating the successful release of the incarcerated uterus. The earlier the diagnosis, the higher the likelihood of successfully releasing the incarcerated uterus.

How to balance protection and development? A comprehensive analysis framework for territorial space utilization scale, function and pattern.

The harmonious coexistence of man and nature is a universally recognized standard to test the rational utilization of multifunctional territorial space, and the planning of territorial space adapted to nature is a scientific guide to balance ecological protection and human development. This study focuses on the inevitable relationship between the scale, function and pattern of territorial space utilization (TSU), and puts forward a process research framework of "background evaluation-advantage comparison-optimization conduction". Based on the evaluation of resource and environment suitability, this paper determines the scale of multifunctional territorial space through the potential conflict identification model of TSU. The location entropy method is used to identify the advantageous functions of the county level, and the matching characteristics of the research results and the current situation are obtained by comparing them with the current plan. Finally, from the county functional zoning to the regional TSU pattern, the corresponding optimization conduction path is designed to form a new development and protection pattern. The empirical results of research area show that: (1) The study area is suitable for urban construction and agricultural production as a whole. The ecological protection is mainly at the general important level, and there is a moderate potential conflict between the development and protection of territorial space. The space scale of urban construction, agricultural production and ecological protection are accounted for 8.77%, 78.71% and 12.52%, respectively. (2) The advantageous function of TSU in county-level administrative units is dominated by single advantageous function, and the number of composite advantageous functions is generally small. The advantageous functional types determined by this research have a high matching with the current plan. (3) Based on the analysis of the scale structure and functional use of territorial space, this paper defines the ecological space that should be strictly protected and the agricultural and urban space that should be moderately developed for production and construction, and sets up elastic development areas. Finally, a strategic pattern of "one corridor, two screens, three circles and four zones" is conducive to the realization of the beautiful vision of the unification of protection and development.

Study on the Effect of Small Faults on the Gas Content in No. 3 Coal Seam of the Changping Mine Field.

To study the influence of small faults on the gas content of Coal Seam 3# in the Changping mine field, the influence scope and degree of small faults on Coal Seam 3# and gas content in the Changping mine field are analyzed based on the field measured data such as the gas content on both sides of the fault, the initial speed of gas emission, and the solidity coefficient of the coal seam, combined with the FLAC3D stress simulation results, and the influence area of small faults is zoned from the perspective of gas control. The analysis results show that the measured gas content in the hanging wall of SF250 fault with a drop of 1.3 m and SF353 fault with a drop of 1.9 m is 7.14 and 9.47 m3/t, respectively, and the gas content in the footwall is 5.29 and 7.41 m3/t, respectively. The gas content in the hanging wall is obviously higher than that in the footwall; the gas content in the coal seam near the small fault surface is slightly lower. With the increase of the distance from the fault surface, the gas content in the coal seam decreases first and then increases; the firmness coefficients of hanging wall coal of small fault are 0.40 and 0.45, respectively, and those of footwall coal are 0.73 and 0.75, respectively. The firmness coefficient of hanging wall coal seam is obviously smaller than that of footwall coal seam. The closer it is to the fault surface, the smaller the firmness coefficient of coal is, and the greater the initial gas release speed is; the permeability coefficient of the coal seam far from the fault surface in the hangingwall of the small fault shows a decreasing trend after an increasing trend. The maximum stress of the coal seam is 21.85 MPa at 14 m from the hangingwall of the fault to the fault, and the minimum stress of the coal seam is 2.79 MPa at 1 m from the footwall of the fault to the fault. The stress of the hangingwall of the fault is greater than that of the footwall of the fault, and the stress concentration area is 14 m from the hangingwall of the fault to the fault.

Gas Emergence Characteristics of the Upper Corner on the 215101 Mining Working Face of the Yue Nan Coal Mine.

To prevent the gas over limit in the upper corner of the 215101 working face of the Yue Nan coal mine, a numerical simulation method was used to analyze the gas concentration in the upper corner of the working face at different air intake volumes and mining velocities. The research results show that the gas concentration in the upper corner is 0.78, 0.52, 0.39, and 0.32% when the wind speed of the intake airflow roadway is 1, 1.5, 2, and 2.5 m/s, respectively, and an optimal wind speed of the intake airflow roadway is selected as 2 m/s. When the wind speed of the intake airflow roadway is 2 m/s, the working face mining velocity is 1, 2, 3, and 4 m/d, and the gas concentration in the upper corner is 0.27, 0.39, 0.58, and 0.83%, respectively, and an optimal working face mining velocity of 3 m/d is selected. Under the optimal mining conditions, the working face wind leakage area is divided, with 0∼30 m of the working face as the main leakage area and 150-180 m as the wind flow compensation area. According to the wind speed in the gob, the wind flow disturbance area is divided, the gob 0-50 m is the wind flow intense disturbance area, which is the main area of the upper corner gas source; the gob 50-62 m is the wind flow medium disturbance area, which is the secondary area of the upper corner gas source; the gob 62-75 m is the slight disturbance area, which has less influence on the upper corner gas concentration; the gob after 75 m is the wind flow undisturbed area, and the upper corner gas concentration is almost unaffected by it.