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Deep reservoirs have a large difference in geo-stress, and compared to shallow reservoirs, multiple clusters of fracturing are usually required to effectively improve the quality of reservoir reconstruction. In this paper, considering the relevant geological parameters of a certain reservoir in the southwest, multi-cluster reservoir fracturing models under three-dimensional conditions based on the cohesive element modelling method are established. Then, the quantitative rules of fluid pressure, fracture length, fracture aperture, fracture area, tensile failure rate, and the fractal dimension of fracture morphology under different fracturing cluster numbers were revealed. The results show that compared to conventional fracturing, multi-cluster fracturing can significantly increase the number of main fractures and improve the effectiveness of reservoir reconstruction. As the number of clusters increases, the number of main fractures in the reservoir increases, but it can also lead to the increase of small opening fractures, which may be unfavourable for the pumping of proppant and subsequent mining. Meanwhile, based on the fractal dimension results of fracture morphology, it was found that under this simulation condition, the number of fracturing clusters had a significant impact on the fractal dimension of fracturing fractures before the fracturing of six clusters, while after the fracturing of six clusters, the impact of the number of fracturing clusters on the fractal dimension of fracturing fractures decreased. Therefore, when considering factors such as the complexity of fractures, multi-cluster fracturing does not necessarily result in more fracturing clusters being better but should be comprehensively considered for optimization. This study has certain reference significance for selecting the spacing between multiple fracturing clusters.

Hydraulic fracturs size inversion plays an important role on evaluating hydraulic fracturing efficiency. Fracture size can be calculated by microseism events or all the pressure data generated by hydraulic fracturing stimulations. These methods are time-consuming. However, the sudden shutoff of pumping can induce a special data known as the water hammer signal. The size of this data is much fewer than others so using it to calculate fracture size is efficient. This study proposes a method of using water hammer signal to work out the hydraulic fracture size. The numerical simulation model is proposed based on the transient flow model to describe the water hammer behavior. The impacts of fracture on water hammer behavior are represented by three parameters (R,C and I). Through these parameters, the fracture size can be calculated. The accuracy of this method is validated by comparing fracture size inversion results between different methods. The results show that the parameter C and R have obvious impacts on water hammer signal and they can cause the amplitude of water hammer signal alternate from 5 to 2 MPa. In addition, this method is accurate for fracture size calculation and the overall error between its results and ones from normal methods is about 6.28%. This method is more suitable for fractures away from horizontal well toe than ones near to well toe. The mean error of fractures away from well toe is only 3.49% but it is 12.75% for fracture near well toe. It is because that the fracture structure is complex near well toe. It indicates that the more accurate relationship between fracture size and parameters (R,C and I) is required for fracture with complex structure.

This article focused on the study of pore structure characteristics of Songhe and Linhua coal samples based on mercury injection experiments and high-pressure isothermal adsorption experiments. The results show that the pore structure of coal samples in the two mining areas is obviously different under the influence of metamorphic degree. The pores of Songhe mine coal samples, which are characteristic of middle-rank coal reserves, are predominantly open cylindrical pores with good connectivity to medium-to-large pores but poor absorption capacity. The tiny and medium pores of Linhua coal samples, which are characteristic of high-level coal reserves, have poor connectivity, dominated by conical pores with mostly closed and semi-closed pores. The pore size distribution of the middle-rank coal sample is multi-peaked, with better developed pore sizes, while the pore size distribution of the Linhua coal sample is bi-peaked, with micro and small pores developed. The pore fractal shape of high-rank coal reserves is higher than that of middle-rank coal reserves, and the complexity of permeable pore space and diffusive pore space of high-order coal reservoirs is higher than that of middle-order coal reservoirs.

ObjectivesThis work aimed to study the long-term outcome and function of a heterotopic replanted finger.MethodsRetrospective analysis of two cases of successful finger reconstruction after finger heterotopic replantation. One case was a severed thumb, and the other case was a severed finger. The average follow-up time was 10 years. The clinical outcome and function of the heterotopic replanted finger, including range of motion, grip strength, and sensory recovery, were analyzed,. A comparative analysis was conducted with patients who underwent thumb replantation in the same period.ResultsThe two heterotopically replanted fingers survived. Five months after the heterotopic replantation surgery, a new thumb was reconstructed using the heterotopically replanted thumb and the free tarsometatarsal joint from the foot. In the other case, the finger was reconstructed 1 year later with a free anterolateral thigh flap and the heterotopically replanted finger. The movement of the thumb, the pinching of the fingers, the clenching of the fist, and the feeling recovery were all good. The patient was capable of independently performing daily life and work activities such as eating, dressing, writing, and so on. There was no significant difference in hand function between the patients who received in situ finger replantation and heterotopic replantation during the same period.ConclusionFor severed fingers that cannot be replanted in situ in an emergency situation, heterotopic replantation and secondary reconstruction may be a feasible and practical surgical method.

ObjectiveThis systematic review and meta-analysis assessed the effects of three types of physical exercise (resistance exercise, aerobic exercise, and group exercise), different exercise intervention times (3 months, 6 months), and different exercise intensities (low, moderate, and high) on the improvement of depressive symptoms in older adults aged ≥60 years, as well as to explore the impact of the sustainability of these physical exercise intervention programs on depressive symptoms in older adults.MethodsThe randomized controlled trials (RCTs) on the effect of physical exercise on depressive symptoms in older adults were retrieved from Cochrane Library, Web of Science, PubMed, and Embase Data. The retrieval time limit is from establishing the database to January 7, 2024. We conducted a meta-analysis using a 95% confidence interval (95% CI) and the standardized mean differences (SMD). The I2 statistic was used to assess the heterogeneity of the outcomes of the studies. When I2 50%, we used the random-effects model. Subgroup and sensitivity analyses investigated heterogeneity origins.ResultsThere are 15 articles reported 20 studies, with a total of 1,346 patients, including 689 in the control group and 657 in the experimental group. The findings demonstrated a notable improvement in depression symptoms among older persons as an immediate result of engaging in physical exercise [SMD = −0.82, 95% CI (−1.19, −0.45)]. The subgroup analysis showed that moderate-intensity physical exercise [SMD = −0.25, 95% CI (−0.47, −0.03)], high-intensity physical exercise [SMD = −0.94, 95% CI (−1.37, −0.51)], resistance exercise [SMD = −0.70, 95% CI (−1.20, −0.20)], and group exercise [SMD = −0.97, 95% CI (−1.89, −0.05)], and the exercise intervention time was 3 months [SMD = −0.81, 95% CI (−1.38, −0.23)] or 6 months [SMD = −0.93, 95% CI (−1.46, −0.41)] were more effective in improving depressive symptoms in older adults.ConclusionThe sustainable resistance and group exercise have a better effect on improving depressive symptoms in older adults. Appropriate exercise intervention time can also ensure the sustainable improvement effect of exercise.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/record_email.php, identifier CRD42023405525.

In this paper, mining-induced deformation for haulage drifts of the hanging wall at Jinshandian Iron Mine is investigated, based on 8 monitoring stations adopted laser convergence meters. Monitoring results are analyzed to divide deformation-time curves into three types: fluctuation type, partial folding type and whole folding type. Moreover, it is found that tensile deformation is easy to occur in the roadway section corresponding to no folding type and partial folding type. And in the roadway section with folding type curve, it is obviously affected by the steeply anti-inclined structural plane. Furthermore, the relative position relationship between mining activities and a monitoring station is established through local coordinate system. Mining effects on roadway deformation are studied based on rectangular coordinate components and polar coordinate components respectively. The critical value of coordinate components that have a significant impact on roadway deformation have been determined. At last, combined with results of mining impact analysis, deformation mechanisms corresponding to the three deformation curves are revealed. These results help determine the appropriate support time and adopt targeted support schemes.

Screening of osteochondral lesions of the talus (OLTs) from MR imags usually requires time and efforts, and in most case lesions with small size are often missed in clinical practice. Thereore, it puts forward higher requirements for a more efficient OLTs screening method. To develop an automatic screening system for osteochondral lesions of the talus (OLTs), we collected 92 MRI images of patients with ankle pain from Qilu Hospital of Shandong University and proposed an AI (artificial intelligence) aided lesion screening system, which is automatic and based on deep learning method. A two-stage detection method based on the cascade R-CNN model was proposed to significantly improve the detection performance by taking advantage of multiple intersection-over-union thresholds. The backbone network was based on ResNet50, which was a state-of-art convolutional neural network model in image classification task. Multiple regression using cascaded detection heads was applied to further improve the detection precision. The mean average precision (mAP) that is adopted as major metrics in the paper and mean average recall (mAR) was selected to evaluate the performance of the model. Our proposed method has an average precision of 0.950, 0.975, and 0.550 for detecting the talus, gaps and lesions, respectively, and the mAP, mAR was 0.825, 0.930. Visualization of our network performance demonstrated the effectiveness of the model, which implied that accurate detection performance on these tasks could be further used in real clinical practice.

Tumor necrosis factor-α–induced protein 8 (TNFAIP8) is a member of the TIPE/TNFAIP8 family which is associated with inflammation and tumorigenesis. The potential role of TNFAIP8 in a tumor immune microenvironment in skin cutaneous melanoma (SKCM) has not yet been investigated. The TNFAIP8 expression was evaluated via gene expression profiling interactive analysis (GEPIA). We also evaluated the influence of TNFAIP8 on overall survival via GEPIA and PrognoScan. After GO and KEGG pathway analyses, the correlation between the TNFAIP8 expression level and immune cells or gene markers of the immune infiltration level was explored by R-language. The result showed the TNFAIP8 expression was significantly reduced in SKCM in comparison with normal control. In SKCM, the TNFAIP8 expression in higher levels was associated with the better overall survival. The high expression of TNFAIP8 was positively correlated with the immune score and promoted immune cell infiltration in SKCM patients. TNFAIP8 can be a positive prognosis marker or new immunotherapy target in SKCM.