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The variation of an accurate global sea level curve has always been a difficult and frontier scientific problem in sedimentary geological research. There are 2 reasons: (1) the deep-time sedimentary record is the comprehensive response to global sea level change and regional movement, but accurately eliminating the regional tectonic effect is also difficult; (2) determining paleo-water depth based on deep-time sedimentary records is still being explored. The Kalpin area of the Tarim Basin in the Late Ordovician experienced an environmental evolution from basin to basin margin to shelf, making it highly sensitive to sea level changes and an ideal area for conducting research on sea level changes based on sedimentary microfacies. The study conducted a detailed field investigation and intensive sampling analysis of the Dawangou section. Based on lithofacies sedimentology, paleontology, etc., the two major fa-cies of the continental shelf and the basin edge were divided, and seven microfacies are distinguished in detail: MF1, brick red/purple microbial micritic limestone; MF2, gray microbial micritic limestone; MF3, gray-green calcareous clay; MF4, gray bioclastic - lithoclastic breccia limestone; MF5, gray bioclastic silty limestone; MF6, gray bioclastic micritic limestone; and MF7, dark gray calcareous clay. Based on advanced microfacies for the sensitive zone of deep-time sedimentary records, the sea level change curve of the Upper Ordovician Kanling and Yingan Formations is constructed, and a set of methods for determining the global sea level curve can be summarized. Our sea level curve is compared with the upper Yangtze region, the southern margin of Ordos, North America, South America, Wales, and the global sea level change, and results indicate that the frequent fluctuations of sea level are similar to North America. The reconstruction plate tectonic results of the study indicate that the Caledonian tectonic movement has global corresponding characteristics during this period. Frequent plane fluctuations are mainly caused by orogenic collisions in different regions. [ABSTRACT FROM AUTHOR]

Objective: To compare the effectiveness of robot-assisted (RA) minimally invasive surgery versus traditional fluoroscopy-assisted (FA) open posterior fixation surgery in treating thoracolumbar fractures with ankylosing spondylitis (AS)., Methods: A clinical data of 21 cases of thoracolumbar fractures with AS who met the selection criteria between December 2016 and December 2023 was retrospectively analyzed. Ten cases underwent RA minimally invasive surgery group (RA group) and 11 cases underwent FA open posterior fixation surgery (FA group). There was no significant difference in gender, age, fracture segment distribution, fracture type, time from injury to surgery, visual analogue scale (VAS) score, and American Spinal Injury Association (ASIA) grading between RA group and FA group ( P >0.05). The operation time, intraoperative blood loss, radiation exposure time, radiation dose, hospital stay, and complications of the two groups were recorded. According to Gertzbein-Robbins criteria, the accuracy of screw implantation was evaluated by CT within 1 week after surgery. During follow-up, pain and nerve function were evaluated by VAS score and ASIA grading., Results: All patients underwent surgery successfully, and there was no significant difference in operation time ( P >0.05). The intraoperative blood loss and hospital stay in the RA group were significantly less than those in the FA group ( P <0.05), and the radiation exposure time and radiation dose were significantly more than those in the FA group ( P <0.05). A total of 249 pedicle screws were implanted in the two groups, including 118 in the RA group and 131 in the FA group. According to the Gertzbein-Robbins criteria, the proportion of clinically acceptable screws (grades A and B) in the RA group was significantly higher than that in the FA group ( P <0.05). Patients in both groups were followed up 3-12 months, with an average of 6.8 months. The VAS scores of the two groups after surgery were significantly lower than those before surgery, and the differences were significant ( P <0.05). The RA group had lower scores than the fluoroscopy group at 1 week and 3 months after surgery ( P <0.05). There was no significant difference in neurological function grading between groups at 1 week and 3 months after surgery ( P >0.05). In the FA group, 1 case of deep infection and 1 case of deep vein thrombosis of lower extremity occurred, while no complication occurred in the RA group, and there was no significant difference in the incidence of complications between groups ( P >0.05)., Conclusion: Both RA minimally invasive surgery and FA open posterior fixation surgery can achieve good effectiveness. Compared with the latter, the former has more advantages in terms of intraoperative blood loss, hospital stay, and accuracy of pedicle screw insertion.

Objective: To compare the effectiveness of robot assisted and C-arm assisted percutaneous kyphoplasty (PKP) in the treatment of single/double-segment osteoporotic vertebral compression fracture (OVCF)., Methods: The clinical data of 108 cases of single/double-segment OVCF who met the selection criteria between May 2018 and October 2019 were retrospectively analyzed. There were 65 cases of single-segment fractures, of which 38 cases underwent "TiRobot" orthopedic robot-assisted PKP (robot group), 27 cases underwent C-arm X-ray machine fluoroscopy-assisted PKP (C-arm group). There were 43 cases of double-segment fractures, including 21 cases in robot group and 22 cases in C-arm group. There was no significant difference in gender, age, T value of bone mineral density, fracture segment distribution, time from injury to operation, and preoperative visual analogue scale (VAS) score, vertebral kyphosis angle (VKA), and height of fractured vertebra (HFV) in the patients with single/double-segments fractures between robot group and C-arm group ( P >0.05). The operation time, the fluoroscopy frequency of the surgeons and the patient, the fluoroscopy exposure time of the surgeons and the patient, the radiation dose of the C-arm; the VAS scores, VKA, HFV before operation, at 1 day and 6 months after operation; and the complications in the two groups were recorded and compared., Results: All patients underwent surgery successfully. The operation time of the single-segment robot group was significantly longer than that of the C-arm group ( t =5.514, P =0.000), while the operation time of the double-segment robot group was not significantly different from that of the C-arm group ( t =1.892, P =0.205). The single/double-segment robot group required three-dimensional scanning, so the fluoroscopy frequency, fluoroscopy exposure time, and radiation dose of C-arm received by the patient were significantly higher than those of the C-arm group ( P <0.05); the fluoroscopy frequency and the fluoroscopy exposure time received by the surgeons were significantly less than those of the C-arm group ( P <0.05). There was no infection, embolism, neurological injury, and adjacent segmental fractures. The single/double-segment robot group showed lower rate of cement leakage when compared with the C-arm group ( P <0.05), all the cases of cement leakage happened outside the spinal canal. The VAS score, VKA, and HFV of the single/double-segment robot group and the C-arm group were significantly improved at 1 day and 6 months after operation ( P <0.05), and the VAS score at 6 months after operation was further improved compared with that at 1 day after operation ( P <0.05). At 1 day and 6 months after operation, there was no significant difference in VAS score between the single/double-segment robot group and the C-arm group ( P >0.05). The VKA and HFV of robot group were significantly better than those of the C-arm group ( P <0.05)., Conclusion: For single/double-segment OVCF, robot assisted PKP has more advantages in correcting VKA and HFV, reducing fluoroscopy exposure of surgeons and bone cement leakage rate; C-arm assisted PKP has more advantages in reducing the operation time of single-segment OVCF and fluoroscopy exposure of patients during operation.

Inflammatory bowel disease (IBD) is a group of intestinal chronic non-specific inflammatory disease with unknown etiology, including ulcerative colitis and Crohn's disease. The risk factors associated with pathogenesis of IBD include environmental factors, genetic factors, and immune factors.Among them, the environmental factors include smoking, drugs, diet, infection and psychological factors.

Objective: To review the progress of the pedicle screw augmentation technique by bone cement., Methods: Recent literature about the pedicle screw augmentation technique by bone cement was reviewed and analysed. The characters were summarized., Results: Pedicle augmentation technique includes the augmentation of ordinary solid pedicle screw and hollow pedicle screw. Both types could increase the fixation strength and gain satisfactory clinical results. Bone cement leakage had a certain incidence rate, but most of cases were asymptom., Conclusion: Bone cement augmentation of pedicle screw is an effective and safe internal fixation for poor bone condition.

Objective: Genetic diversity of the rhizobial bacteria nodulating Tibetia himalaica in the eastern part of Qinghai-Tibet Plateau (Ganzi State, Sichuan) were evaluated., Methods: The pure culture method was used for isolating the rhiobial strains from the nodules. BOXAIR, 16S rDNA sequences, 16S rDNA PCR-RFLP and Principal Component Analysis (PCA) were used to determine the genetic diversity and phylogenetic relationships. The growth in different salt contents, pH and temperatures were tested., Results: In total 22 strains were isolated from 12 samples in 8 counties. The strains tested were classified into 4 clusters in 16S rDNA PCR-RFLP, and 8 clusters were formed in BOXAIR. The 16S rDNA Simpson genetic diversity index was D = 0. 872. The strains tested were closely related to Rhizobium (11/22 strains), Mesorhizobium (4/22 strains) and Rhizobium- Agrobacterium (7/22 strains). All strains could regularly grow in YMA medium amended with 1% NaCl, and 15/22 strains could grow in 4% NaCl. SCAU679, SCAU694 and SCAU706 could adapt to 7% NaCl, while SCAU689 could tolerant 8% NaCl. Among the strains tested, 15 strains could grow in the pH range from 4.0 to 11; 16 isolates grew well from 4 to 45 degrees C, and all of 22 strains could grow at 28 degrees C after treatment at 60 degrees C for 10 min., Conclusion: This study revealed the high genetic diversity of the rhizobia isolated from Tibetia himalaica in the eastern part of Qinghai-Tibet Plateau. The strains tested were adapted to high salt, different range of temperatures and pH.

Objective: To explore the effect of basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) on the growth of muscle derived stem cells (MDSCs)., Methods: MDSCs were isolated from hindlimb muscle of 15 new born Kunming mice through serial preplates. 2% fetal bovine serum-containing DMEM was used to induce MDSCs to differentiate into skeletal muscle lineage. The expressions of stem cell marker Sca-1 and skeletal muscle cell marker alpha-Sarcomeric actin were examined by immunocytochemistry. The effect of bFGF and EGF on the proliferation of MDSCs was determined by MTT colorimetric microassay. The solo effect of bFGF or EGF at different concentrations (6.25, 12.50, 25.00, 50.00, and 100.00 ng/ml) was examined at 96 h and the combined effect (100.00 ng/ml) was examined at 24, 48, 72 and 96 h., Results: MDSCs were successfully isolated from the hindlimb of neonatal mice. Over 90% of MDSCs showed Sca-1 positive immunoreactivity. MDSCs could give rise to alpha-Sarcomeric actin positive myotubes in differentiation cultures. The proliferative effect of bFGF and EGF on MDSCs increased with the elevated concentration. bFGF began to show significant proliferative effect at 12.50 ng/ml (P<0.05). The effect increased significantly when the concentration reached 25.00 ng/ml from 12.50 ng/ml (P < 0.01) and reached a saturation point. The effect at 50.00 ng/ml or 100.00 ng/ml showed no significant increase when compared with that at 25.00 ng/ml. EGF had a similar effect to bFGF except that the saturation concentration was 50.00 ng/ml. EGF showed significant effect at 72 h and bFGF at 96 h (P<0.01). When they were applied together, significant effect was shown at 24 h (P<0.01) and much higher effect was observed at 48, 72 and 96 h (P<0.05)., Conclusion: Both bFGF and EGF can promote the proliferation of MDSCs. The combined application reacts faster and stronger.

The spatial pattern of ecological landscape during land utilization in Fukang is heavily influenced by natural difference and the scale of water and land resource development. Analyses on the spatial pattern based on different zones and indexes showed that from 1987 to 1998, the change of the spatial pattern of ecological landscape during land utilization in Fukang was mainly the increase of plantation area in pluvial fan and the decrease in alluvial plain. The case was on the contrary about badlands. The acreage of woodland decreased in lower mountains, uplands and alluvial plain, but no variety in alluvial plain. The acreage of grassland increased in lower mountains and uplands, while decreased in other fields. The acreage of town increased in each sample field, while that of water area remained uncharged. The landscape diversity and evenness was descending, the dominance was ascending in lower mountains and in pluvial fan, while it was reverse in alluvial plain. Accessorial fragmentation showed the increasing influence of human beings. The change of the spatial pattern of ecological landscape in Fukang focused on the acreage alteration of plantation and badlands in pluvial fan and alluvial plain. The key factor was the dynamic variation of water-salt in water and soil resource utilization. Terrain and land utilization were the key factors affecting water table, and the continuous changes of the water table worked on the spatial distribution of soil water-salt.