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【Background】 Nonpoint source pollution can cause eutrophication and biodiversity loss in rivers and lakes. In China, nonpoint source pollution from agriculture has become an environmental concern and understanding its composition and spatial distribution in watershed is essential to improving its management and mitigating its detrimental impact. 【Objective】 The purpose of this paper is to study the impact of land usage on spatiotemporal change in nonpoint source pollution, and elucidate its relationship with watershed landscape. 【Method】 We took the Burhatong river basin as an example and used the distributed hydrological model SWAT to simulate dynamics of nonpoint source pollution induced by four land use changes from 1986 to 2016. The Fragstats 4.2 software was used to calculate the landscape pattern index of the sub-basins, and its relationship with nonpoint source pollution was analyzed using the CANOCO5.0 software. 【Result】 ①The determination coefficient and the Nash efficiency coefficient of the runoff and total phosphorus amount simulated by the SWAT in calibration and verification were all higher than 0.6. The model can thus be used to simulate water quality in the watershed. For the four land usage changes from1986 to 2016, the total annual phosphorus load simulated by the model was 74.04, 73.78, 82.50 and 128.31 tons, respectively. ②There is a close relationship between nonpoint source pollution and landscape pattern. In terms of landscape composition pattern, the total phosphorus load was negatively correlated to forest land, while positively correlated to farmland and construction land. In terms of landscape spatial pattern, the total phosphorus was positively correlated to fragmentation of forest land, while negatively correlated to fragmentation of farmland. Increasing materials flow between patches and enhancing patch aggregation can reduce nutrient loss, while increasing landscape heterogeneity and complexity increases pollution risk. 【Conclusion】 Nonpoint source pollution in the watershed of Burhatong basin has increased steadily, especially in the slopped areas in the north and agricultural and urban areas in the east. Reducing forest land fragmentation and controlling urban nonpoint source pollution can help mitigate its detrimental impact.

Based on the analyses of the situation and distribution of casing damage in the Tarim Oilfield, it was considered that there are six major factors causing the casing damage: (1) There are flowing rock or highly permeable formation around the casing; (2) The well bore structure is unreasonable; (3) The up hole elevation of cement in the drilling design is not high enough, or the cementing quality does not conform to the rules; (4) The quality of casing grading hoop is not up to the required standard; (5) Collapse resistance decreased due to the corrosion, wear, and special down hole operation; (6) The unreasonable development factors. According to the present situation of the casing damage, the comprehensive countermeasures of “defense”, “diagnosis”, “treatment” for repairing the casing-damaged wells were developed. For the casing-damaged wells, 3 ways, taking underground work sit sealing to suppress, engineering logging and static temperature gradient, were used to find a leakage. During 1998-2009, casing damages happened in 71 wells, and 87 places were damaged in total. After determining the position of the casing damages, 3 ways were employed to repair the casing-damaged wells, cement squeezing, using packer to the selected segment, tube expanding subsidies. Fifty-seven casing-damaged wells were repaired, of which, 46 wells were recovered on production. The success ratio is 80.70%. Key words: Tarim Oilfield, development, casing-damaged well, distribution of casing damage, casing damage prevention, countermeasure

The development of the Jilake gas condensate field is dominated by production of old wells, with complication of well status, serious impact of edge-bottom water, and difficulty in development and adjustment. Through integration of formation water salinity analysis, color and density change of oil samples, diagnostic curve characteristic of modern production decline analysis and characteristic analysis of production water, the reason for water production is analyzed as follows: gas wells with low water production are affected by local connate water, while gas wells with high water production are influenced by the bottom-edge water. Integrated with domestic and overseas modeling of oil rim gas condensate reservoir, the fine geological model is built by Petrel geo-modeling software, and the approaches of non-equilibrium initialization and parameters initial value assignment is used to form the initialization model of the gas condensate field, in order to correctly portrait the oil rim and local connate water. On the basis of single-well water production analysis, the geological model is corrected through performance dynamic history match. The result provides a base and foundation for later development adjustment of this gas condensate field. 摘要: 针对吉拉克凝析气田目前基本采用老井生产, 井况复杂, 边底水影响严重, 开发调整难度大等实际情况, 基于对气田综合地层水矿化度、油样颜色变化和油样密度变化、现代产量递减分析诊断曲线以及单井产水特征等的研究, 对气藏单井产水原因进行了分析, 认为低产水井受局部非均质性形成的共存水影响、高产水井受边底水影响而产水。为了正确表征油环及局部共存水的分布特点, 综合国内外带油环凝析气藏建模方法, 利用Petrel软件建立该气藏精细地质模型, 并采用非平衡初始化方法及赋初始参数场的形式建立了气藏初始化模型。在单井产水分析基础上, 通过数值模拟历史拟合对模型进行修正, 为后期气藏开发调整提供了基础和依据。 Key words: water production analysis, gas condensate field, reservoir simulation, oil rim, bottom-edge water

Objective: To investigate the effectiveness of arthroscopic autologous iliac bone grafting with double-row elastic fixation in treatment of recurrent anterior shoulder dislocation combined with massive glenoid bone defects., Methods: Between January 2018 and December 2021, 16 male patients with recurrent anterior shoulder dislocation combined with massive glenoid bone defects were treated with arthroscopic autogenous iliac bone grafting and double-row elastic fixation. The patients were 14-29 years old at the time of the first dislocation, with an average age of 18.4 years. The causes of the first dislocation included falling injury in 5 cases and sports injury in 11 cases. The shoulders dislocated 4-15 times, with an average of 8.3 times. The patients were 17-37 years old at the time of admission, with an average age of 25.1 years. There were 5 left shoulders and 11 right shoulders. The preoperative instability severity index (ISIS) score of the shoulder joint was 5.8±2.1, and the Beighton score was 4.3±2.6. The University of California Los Angeles (UCLA) score, Constant score, American Shoulder and Elbow Surgeons (ASES) score, and Rowe score were used to evaluate shoulder function, and the degree of the glenoid bone defect repair was observed based on CT after operation., Results: All incisions healed by first intention, and no complication such as incision infection or neurovascular injury occurred. The patients were followed up 12 months. At 12 months after operation, UCLA score, Constant score, ASES score, and Rowe score all significantly improved when compared with the scores before operation ( P <0.05). CT imaging showed the degree of glenoid bone defect was significantly smaller at immediate, 6 and 12 months after operation when compared with that before operation ( P <0.05), and the bone blocks healed with the scapula, and bone fusion had occurred at 12 months., Conclusion: Arthroscopic autologous iliac bone grafting with double-row elastic fixation is a safe treatment for recurrent anterior shoulder dislocation combined with massive glenoid bone defects, with good short-term effectiveness.

Post-traumatic osteomyelitis is one of the most common disorders of bone infection, which is secondary to open fracture caused by machinery injury, traffic accident, and it is also the main manifestation in the postoperative infection of open fracture. After trauma, bacteria invade bone tissue and reproduce rapidly in large quantities, which easily leads to osteomyelitis. Patients are often complaint of pain at the affected limb, loss of function, or even amputation due to deteriorated infection, resulting in loss of labor capability and poor quality of life. Because the diagnosis and treatment are not timely and standard, the treatment for post-traumatic osteomyelitis is often delayed, resulting in the difficulty of clinical cure. It also makes patients and their families bear a serious financial burden. However, the diagnosis and treatment for this disease is difficult for orthopedic physicians. In recent years, imaging methods (such as CT and MRI) combined with immune techniques have significantly improved the diagnostic accuracy and early diagnosis ability. The application of new diagnostic technologies (such as gene chip and second-generation sequencing) also makes the diagnosis more convenient and sensitive. The novel reconstruction and repair surgery (such as Ilizarov technology and Orthofix LRS technology) provides new treatment direction for orthopedic surgeons and patients.

Rotator cuff injuries are the most common cause of shoulder pain and dysfunction. Ideal animal shoulder models should have similar shoulder anatomy and function as human, and are able to replicate the microenvironment change after tendon injury. At present, a variety of animal models including rat, mouse, rabbit, sheep, canine, bovine, and primate have been used to study the mechanism of rotator cuff injury, effects of different repair techniques, and factors affecting tendon to bone healing. Although large animal models are more anatomically similar to humans, small animal models are more convenient in revealing the biological mechanism of rotator cuff injury and healing. Choosing appropriate animal models based on research objectives and establishing new small animal models play a critical role in revealing the mechanism of rotator cuff diseases and developing novel treating strategies.

Objectives: To explore the safety and effectiveness of arthroscopic reconstruction of coracoclavicular ligament by suspensory fixation to manage the acute acromioclavicular joint dislocation., Methods: From January 2016 to December 2017, 18 cases of acute acromioclavicular joint dislocation were carried out with arthroscopic reconstruction of coracoclavicular ligament by double Endobutton plate suspensory fixation. Anteroposterior view X-ray plain radiographs were obtained on the second day, 6 months and 12 months after the surgery, MRI was performed in 1 year after operation. Meanwhile, subjective and objective scoring were obtained by Vsual Analogue Scale (VAS), Rating Scale of the American Shoulder and Elbow Surgeons (ASES) and University of California at Los Angeles Shoulder Rating Scale (UCLA)., Results: All patients were followed up for 12 to 30 months (an average of 18 months). There was no patient with infection, neurovascular injury, loosening and breakage of internal fixation, re-dislocation of acromioclavicular joint, clavicular fracture, coracoid process fracture, etc. Postoperative X-ray showed that all acromioclavicular joints were completely relocated. The follow-up of MRI after 1 year showed no obvious dislocation of acromioclavicular joint and good recovery of acromioclavicular space. Postoperative shoulder joint function, VAS, ASES, UCLA and acromioclavicular distance were significantly improved compared with those before surgery, with statistically significant differences (all P <0.05)., Conclusions: Arthroscopic reconstruction of coracoclavicular ligament by suspensory fixation to manage the acute acromioclavicular joint dislocation has the advantages of minimal invasive, rapid functional recovery and less complications and satisfactory early clinical results.

Objective: To explore the effectiveness and safety of pie-crusting the medial collateral ligament release (MCL) in treating posterior horn of medial meniscus (PHMM) tear in tight medial tibiofemoral compartment of knee joint.
 Methods: Thirty-two consecutive patients with PHMM tear in tight medial tibiofemoral compartment of knee joint were admitted to our department from January, 2013 to December, 2014. All patients were performed pie-crusting the MCL release at its tibial insertion with 18-gauge intravenous needle. All patients were evaluated by valgus stress test and bilateral valgus stress radiograph at postoperative 1st day, 4th week and 12th week. Visual Analogue Scales (VAS), Lysholm scores, Tegner scores and International Knee Documentation Committee (IKDC) scores were recorded at the 1st, 3th, 6th month follow-up, then follow-up every 6 months.
 Results: The mean follow-up was 28 (24-36) months. All cases were negative in valgus stress test. MCL rupture, femoral fracture, articular cartilage lesion and neurovascular injury were not found at the last follow-up. The median medial joint space width of affected side and unaffected side for valgus stress radiographs were 6.8 mm and 4.3 mm (P<0.05) at the 1st day, 5.5 mm and 4.2 mm 
(P<0.05) in the 4th week and 4.8 mm and 4.3 mm (P>0.05) at the 12th week, respectively. VAS scores was changed from 4.5±1.5 preoperatively to 1.7±1.0 at the final follow-up (t=16.561, P<0.05). Lysholm scores was changed from 52.3±5.8 preoperatively to 93.2±6.3 at the final follow-up (t=-41.353, P<0.05). Tegner scores was changed from 4.1±1.1 preoperatively to 5.5±0.6 at the final follow-up (t=-18.792, P<0.05). IKDC scores was changed from 54.5±6.2 preoperative to 93.8±4.5 at the final follow-up (t=-38.253, P<0.05).
 Conclusion: Pie-crusting the medial collateral ligament release is a safe, minimal invasive and effective surgical option for posterior horn of medial meniscus tear in tight medial tibiofemoral compartment of knee joint.

Objective: To explore the clinical outcomes of anatomical double-bundle medial patellofemoral ligament (MPFL) reconstruction with double suture anchor technique in treating patellofemoral instability in adolescent.
 Methods: Twenty-five young people with patellofemoral instability (25 knees) in our department from January 2013 to December 2014 were enrolled for this study. All patients were performed anatomical double-bundle MPFL reconstruction with arthroscopic-assisted suture anchors technique in the patella, and fixed in the femoral socket with absorbable interference screw. All patients are evaluated by different methods, including patient's satisfaction, patellar apprehension test, recurrent subluxation/dislocation, CT assessment of bone tunnel and patellar tilt angle. Lysholm scores, Tegner scores and Kujala scores were recorded at the final follow-up.
 Results: The mean follow-up was 24 (range 20-40) months. All cases were observed in negative patellar apprehension test. Infection, recurrent subluxation/dislocation and patellar fracture were not found at the last follow-up. CT results demonstrated that the tunnel position were good. The patellar tilt angle was decreased from 21.6°±2.3° to 10.5°±1.6° (P<0.05); the Lysholm scores was increased from 51.7±5.3 to 93.8±6.5 (P<0.05). Tegner scores was increased from 4.1±1.1 to 5.5±0.6 (P<0.05). Kujala scores was increased from 53.5±6.4 to 94.6±4.3 (P<0.05).
 Conclusion: Arthroscopic-assisted anatomical double-bundle MPFL reconstruction with the suture anchors technique is a safe, minimal invasive and effective surgical option for treating patellofemoral instability in adolescent.

Objective: To explore the therapeutic efficacy of arthroscopic reconstruction of anterior cruciate ligament (ACL) with autologous multi-stranded semitendinous tendon (ST)., Methods: From September 2000 to December 2004, 50 cases of ruptures of ACLs were diagnosed by clinical and arthroscopic examinations. There were 32 males and 18 females with an average age of 26.3 years (18-51 years). The locations were left knee in 31 cases and right knee in 19 cases. All patients had the history of knee joint injury. Arthroscopy showed 26 cases of rupture, 14 cases of defect, 4 cases of avulsion and 6 cases of laceration. All patients were operated upon arthroscopically by using autologous multi-stranded ST. Plaster splints were used for 4 weeks after operation. The result was estimated by AO Yingfang's standards and Lysholm knee scores., Results: All patients achieved healing by the first intention. The extension and flexion function was restored normal at 8-10 weeks. The patients were followed up averagely 1 year and 8 months (6-48 months). The results of drawer test and Lachman test were positive in 3 cases and suspiciously positive in 8 cases. The results were excellent in 23 patients, good in 18 and fair in 9. Lysholm knee scores were 40.57+/-10.68 preoperatively and 86.43+/-9.33 postoperatively, showing significant difference (P < 0.01)., Conclusion: Arthroscopy reconstruction of ACL with autologous multi-stranded ST may be one of the excellent methods bringing less injury.

Objective: To investigate the best time of the glycerol test on Meniere's disease patients., Method: The glycerol test was carried out two times on 72 Meniere's disease patients, one time in the period of onset and the other in the period of intermission., Result: The positive rate in the period of onset (83.3%) was far higher than in the period of intermission(43.1%), additionally, the positive rate is irrelevant to the degree of hearing impairing or the course of disease., Conclusion: The glycerol test should be carried out in the period of onset as possible as you can to the suspicious patients.