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[Objective] The change characteristics and influencing factors of vegetation coverage and its spatial distribution in the Binchang mining area were analyzed, and the ecological status of the mining area was evaluated in order to provide a scientific reference and theoretical basis for reclamation and ecological restoration of the mining area. [Methods] Landsat Surface Reflectance Tier 1 data (30 m resolution) from 1986 to 2021 were obtained from the Google Earth Engine cloud platform. Based on a pixel binary model, the trend analysis method and F-test were used to quantitatively analyze the temporal and spatial variation of vegetation coverage in the Binchang mining area over many years. Geodetector was used to analyze the spatial heterogeneity of vegetation coverage. [Results] ① Vegetation coverage in the Binchang mining area increased from 1986 to 2021, and the overall growth trend was good (average growth rate of 0.64%/a). The average multi-year vegetation coverage in the study area was relatively high, with the area of medium coverage and greater accounting for 87.14% of the total area. The spatial distribution was characterized as “higher in the southeast and lower in the northwest”. ② In terms of the change trend of vegetation coverage, the study area was dominated by significantly improved areas, accounting for 56.65% of the total area. However, there were still some areas with significant vegetation degradation, mainly concentrated in the area near urban river roads. ③ The factors influencing vegetation coverage followed the order of slope > elevation > annual precipitation > GDP> population density > annual average temperature > vegetation type > soil type. The interaction between slope and annual precipitation had the strongest influence on the spatial heterogeneity of vegetation coverage. [Conclusion] From 1986 to 2021, the vegetation coverage in the Binchang mining area was good, showing a significant growth trend as a whole, and the vegetation improvement was obvious. The dominant factor affecting the spatial heterogeneity of vegetation coverage in the study area was slope.

Objective To investigate the effect of FOCUS-PDCA management mode in standardizing medication of ophthalmic drugs in patients undergoing ambulatory eye surgery, and provide reference for continuous improvement of the nursing quality of ambulatory eye surgery. Methods A non-concurrent control trial was conducted, and patients undergoing ambulatory eye surgery were assigned to the control group (n=146)and the observation group (n=154). The control group received routing nursing management during operation period. The FOCUS-PDCA management mode was adopted in standardizing medication of ophthalmic drugs for patients in the observation group. The rate of qualified self-medication of ophthalmic drugs, awareness and knowledge about ophthalmic drugs and patient satisfaction were measured and compared between groups. Results The rates of proper storage of ophthalmic drugs, proper administration time of ophthalmic drugs and qualified self-medication of ophthalmic drugs in the observation group were higher than those in the control group (P

An on-line pyrolysis-vacuum ultraviolet photoionization mass spectrometer was built for the analysis of pyrolysis products of tobacco. Vacuum ultraviolet photoionization is a “soft” ionization method producing few or no fragments of molecular ions, and identifing the complex pyrolysis products in real time. In this work, the pyrolysis of tobacco leaves from various stalk positions (B2F, C3F and X2F) at 300, 400, 500, 600 and 700 ℃, and the effects of reaction temperature on the pyrolysis products intensity were studied. A series of mass spectra of pyrolysis products were obtained, and the changes of products at different pyrolysis temperatures were compared. The analysis results of products at different pyrolysis temperatures were helpful to reveal the formation mechanism of compounds in different parts of cut tobacco during pyrolysis/combustion. The dynamic curves of pyrolysis products such as vinylamine (m/z 43), isoprene (m/z 68) and dimethylfuran (m/z 96) with time were further observed at 500 ℃, so as to master the dynamic change process of pyrolysis reaction. It was found that the increase of temperature can dramatically shorten the reaction time. Generally, the primary products will be formed at the medium cracking temperature, and gradually pyrolyzed into secondary products with the increase of temperature, the secondary products will be accompanied by higher temperature cracking and thermal synthesis to form tertiary products. In order to quickly screen and identify different parts of tobacco, principal component analysis (PCA) was used to analyze the mass spectra of pyrolysis products, and the differences of chemical components in different parts of tobacco were identified. Then, the components with m/z 58, 96, 110 were the typical products of X2F, the components with m/z 43, 126 were the representative products of C3F, and the main representative product of B2F was the component with m/z 84. Based on the above results, photoionization mass spectrometry was important to study the dynamic changes of tobacco pyrolysis products, the pyrolysis products of different parts of tobacco were quickly identified at 300-700 ℃, and the main pyrolysis products were summarized. By comprehensively evaluating the main components and relative content of pyrolysis products, tobacco samples from different parts can be quickly distinguished.

Objective To investigate whether hypocalcemia is associated with poor prognosis in COVID-19 patients. Methods A retrospective analysis was performed on 2 651 COVID-19 patients admitted to Wuhan Huoshenshan Hospital from February 4, 2020 to April 11, 2020. They were divided into low and normal calcium groups according to their serum calcium level lower than 2.11 mmol/L or not. Their basic demographic characteristics, results of laboratory tests, treatment, complications and outcomes were analyzed and compared between the 2 groups. COX regression model was used to analyze whether low calcium is an independent risk factors for poor outcomes in COVID-19 patients. Results The low calcium group had significantly higher ratios of mechanical ventilation, extracorporeal membrane oxygenation (ECMO) and ICU occupancy (P < 0.05); obviously higher incidences of sepsis, shock, hypoproteinemia, respiratory failure, coagulation disorders, acute kidney injury, acute myocardial injury, acute respiratory distress syndrome (ARDS), and even mortality (P < 0.05); and remarkably longer length of hospital stay (P < 0.001) when compared with the normal calcium group. The blood calcium level of mild and common, severe, and critical COVID-19 patients was 2.17 (2.11, 2.24), 2.13 (2.04, 2.21), and 2.03 (1.89, 2.18) mmol/L, respectively, and significant differences were seen among the patients (P < 0.05). The calcium level was in a decreasing trend with the severity of COVID-19 (P < 0.05). The calcium level was statistically lower in the dead patients than those survival [1.97 (1.87, 2.03) vs 2.17 (2.09, 2.23), P < 0.001]. Multivariate Cox regression analysis indicated that serum calcium concentration < 2.11 mmol/L was an independent risk factor for poor prognosis of COVID-19 (HR=5.695, 95%CI : 2.363~13.725, P < 0.001). Conclusion Low blood calcium level is an independent risk factor for poor prognosis in COVID-19 patients. Correction for hypocalcemia may be an important strategy to improve the prognosis of COVID-19 patients.

The influence of different multi-stage aging heat treatment on microstructure and corrosion resistance of 7056 alloy was investigated by the measurements of transmission electron microscope(TEM), scanning electron microscope(SEM),mechanical properties and electrical conductivity, exfoliation corrosion, slow strain rate testing(SSRT), Tafel cyclic polarization. The results show that after over-aging and re-aging heat treatment, the solute atoms precipitate again, and the volume fraction of the precipitate in the matrix increases, the grain boundary precipitates coarsen and become discontinuous, the precipitate-free zone becomes wider. Compared with 120℃/24h pre-aging,120℃/6h has advantage in terms of dissolution of finer precipitates and the growth of large coarse phase. Re-aging heat treatment can improve the strength and conductivity of over-aging alloys;compared with peak aging and retrogression and re-aging, the loss of tensile strength of the alloy is not significant, while the conductivity increases obviously. After over-aging and re-aging heat treatment, continuous anodic dissolution is avoided effectively, and the exfoliation corrosion resistance and stress corrosion cracking is enhanced.

Objective To investigate the effects of store-operated calcium entry (SOCE) on the bio-functions of vascular endothelial cells (ECs) based on human umbilical vein endothelial cells (HUVECs). Methods The cultured HUVECs were divided into control group and 2-APB (SOCE inhibitor, 10, 25, 50, 75 and 100 μmol/L) intervention groups. The SOCE was measured by the fluorescence intensity of calcium probe in 5 min after 2-APB treatment (n=10). The proliferation (n=9) and migration (n=10) capacities of HUVECs after different doses of 2-APB treatment (50, 75 and 100 μmol/L) for 24 h were measured by CCK-8 assay and Transwell assay. In addition, at 2 h after 2-APB treatment, Griess reagent kit was employed to detect the production of NO (n=6), and Western blotting was used to measure the expression of eNOS (n=3) in different groups. Results Low doses of 2-APB (10 and 20 μmol/L) showed an inhibitory effect on SOCE, but the inhibition had no statistical significance (P < 0.05), while high doses of 2-APB (50, 75 and 100 μmol/L) inhibited SOCE significantly (P>0.05). Treatment of 2-APB (50, 75 and 100 μmol/L) also suppressed the proliferation (decreased by 33.2%, 46.3% and 61.2%, respectively when compared with control cells, all P < 0.05), the migration (decreased by 33.5%, 54.3% and 64.9%, respectively when compared with control cells, all P < 0.05), NO production (decreased by 40.5%, 61.9% and 73.1%, respectively when compared with control cells, all P < 0.05) as well as the synthesis of eNOS (decreased by 45.1% and 62.4% in the 75 and 100 μmol/L treated cells, respectively when compared with control cells, both P < 0.05) in ECs. Conclusion SOCE is involved in the proliferation and migration of ECs, and inhibition of SOCE can induce ECs dysfunction, which may act through suppressing eNOS synthesis.

To study the deformation and stress of ring-flexspline in harmonic gear under actual working conditions,an interference fit model is applied to solve the problem of assembling between the wave generator and flexspline with large deformation. Further more experiments are performed to test the validity of this method. Then the finite element numerical calculations of the whole harmonic gear are obtained under no-load and rated load on the base of the model. At last,the deformation and stress distributions law of flexspline in the no-load and load are analyzed by data processing. The results show that the stress distribution of the flexspline has its minor value along the neutral layer of flexspline ring,and the maximum stress is located on the tooth root which mainly is tangential. The deformation and stress increment of flexspline under rated load are0. 46% and 93. 6% respectively relative to the no-load. It also shows that the load has little effect on flexspline deformation,but a strong influence on its stress. The finite element analysis results which fit well with related literature calculations proved that the interference fit model is effective,so it can provide a more precise method to study harmonic gear drive in accordance with the actual working conditions.

Objective: To compare screw versus Kirschner wire fixation in the treatment of lateral humeral condyle fractures in children., Methods: A systematic search was conducted in PubMed, Embase, the Cochrane library, Web of Science, China National Knowledge Internet(CNKI), Wanfang Datebase from in ception to February 2022. Studies comparing screws and Kirschner wire fixation in the treatment of lateral humeral condyle fractures in children were included. Outcome measures included and excluded by a set of inclusion and exclusion criteria and evaluated for their quality, their excellent and good rate of fracture healing, malunion, delayed union or nonunion, infection, limitation of elbow flexion or extension(>10°) were extracted and analyzed using software Rev Man 5.3., Results: A total of 9 retrospective studies involving 647 patients were included, with 255 patients in the screw fixation group(including screw combined with Kirschner wire) and 392 patients in the Kirschner wire fixation group. Meta analysis showed the following:infection rate in the screw group was significantly lower than that in the Kirschner wire group[ OR =0.22, 95% CI (0.09, 0.56), P =0.001]. There were no significant differences between the 2 groups in excellent and good rate of fracture healing, malunion rate( P >0.05). Subgroup analysis showed that infection rate in the screw-only group was significantly lower than that in the Kirschner wire group[ OR =0.18, 95% CI (0.05, 0.65), P =0.009]., Conclusion: For lateral humeral condyle fractures, Screw fixation alone had a lower infection rate than kirschner wire fixation and screw combined with Kirschner wire fixation. There were no significant differences in the excellent and good rate of fracture healing, malunion. In terms of postoperative efficacy and safety of internal fixation, orthopaedic surgeons are more likely to recommend screws for fixation of lateral humeral condyle fractures in children.

Objective: To explore clinical efficacy of autologous bone grafts and bone substitute for the treatment of tibial plateau fractures by Meta analysis., Methods: Controlled clinical studies on autogenous bone transplantation and bone substitutes in treating tibial plateau fractures published on PubMed,Web of Science,CNKI,Wanfang and other databases from January 2005 to August 2022 were searched by computer. Literature screening and data extraction were performed according to randomized controlled trial(RCT),and the quality of RCT were evaluated by using intervention meta-analysis criteria in Cochrane manual. Meta-analysis of joint depression,secondary collapse rate of articular surface,blood loss,operative time and infection rate between two methods were performed by Rev Man 5.3 software., Results: Seven RCT studies (424 patients) were included,296 patients in bone replacement group and 128 patients in autograft group. Operative time [ MD =-16.79,95% CI (-25.72,-7.85), P =0.000 2] and blood loss[ MD =-70.49,95% CI (-79.34,-61.65), P <0.000 01] between two groups had statistically differences,while joint depression[ MD =-0.17,95% CI (-0.91,0.58), P =0.66],secondary collapse rate of joint surface[ RR =-0.74, 95% CI (0.35,1.57), P =0.43],infection rate [ RR =1.21,95% CI (0.31,4.70), P =0.78] between two groups had no differences., Conclusion: The effects of bone substitute and autograft for the treatment of tibial plateau fracture have similar effects in terms of joint depression,secondary articular surface collapse rate and infection rate. However,compared with autologous bone transplantation,bone replacement could reduce blood loss and shorten operation time.

Objective: To compare the long-term follow-up effect and complications of ceramic on ceramic (CoC) interface and ceramic on polyethyleneon ceramic (CoP) interface in primary total hip arthroplasty, and provide clinical evidence., Methods: Search PubMed, EMBase, the CoChrane Library databases, Web of science, Wanfang database, and CNKI from January 2000 to September 2021, screening and inclusion of randomized controlled trials (RCTs) comparing the long-term efficacy and complications of CoC interface and CoP interface in total hip arthroplasty. Literature screening, quality evaluation and data extraction were carried out according to the inclusion and exclusion criteria, using Review Manager 5.3 statistical software. The software was used to perform statistical analysis on joint function, revision, prosthesis fracture, abnormal joint noise, and prosthesis wear rate after CoC or CoP., Results: Seven RCTs studies were included, including 390 cases of hips with CoC artificial joints and 384 cases of hips with CoP artificial joints. The long-term joint function improvement of CoC and CoP artificial joints was similar and there was no significant differences, with an average difference was MD =0.63, 95% CI =(-1.81, 3.07), P =0.61. About the postoperative complications, CoC artificial joints have higher incidence rate of abnormal joint noise, with odds ratio ( OR )=11.05, 95% CI =(2.04, 59.84), P =0.005. CoP artificial joints wear faster, with an average MD =-87.11, 95% CI =(-114.40, -59.82), P <0.000 1. There was no significant difference between the two groups in the replacement-related complications such as joint dislocation, prosthesis loosening, osteolysis, and the rate of prosthesis revision caused by various reasons., Conclusion: The clinical function results and complications of CoC artificial joints are comparable to those of CoP artificial joints. Although CoP artificial joint prosthesis has a faster wear rate, it does not affect joint function and increase complications, and there is no abnormal joint noise. CoC is expensive and the long-term efficacy is equivalent to CoP. Clinicians should consider cost performance when choosing CoC.

Objective: To systematically evaluate the clinical efficacy of arthroscopy and traditional incision in the treatment of tibial avulsion fracture of anterior cruciate ligament (ACL)., Methods: From July 2010 to July 2020, clinical comparative trial about arthroscopy and traditional incision in the treatment of ACL tibial avulsion fracture was conducted by using computer-based databases, including Embase, Pubmed, Central, Cinahl, PQDT, CNKI, Weipu, Wanfang, Cochrane Library, CBM. Literature screening and data extraction were carried out according to the inclusion and exclusion criteria, and the quality of the included literature was evaluated by improved Jadad score and Ottawa Newcastle scale (NOS). The operation time, hospital stay, fracture healing time, knee range of motion, postoperative excellent and good rate, complication rate, Lysholm score, International Knee Documentation Committee (IKDC) score and Tegner score were statistically analyzed by Review Manager 5.3 software., Results: Finally, 16 literatures were included, including 1 randomized controlled trial and 15 non randomized controlled trials, with a total of 822 patients (405 in arthroscopy group and 417 in traditional incision group). Meta analysis showed that the operation time [MD=-9.03, 95% CI(-14.36, -3.70), P <0.001], hospital stay [ MD =-5.81, 95% CI (-9.32, -2.31), P =0.001] and fracture healing time [ MD =-14.61, 95% CI (-17.93, -11.28), P <0.001] in the arthroscopy group were better than those in the traditional incision group. The incidence of complications in arthroscopy group was lower than that in traditional incision group[ OR =0.15, 95% CI (0.07, 0.33), P <0.001]. The postoperative excellent and good rate[ OR =4.39, 95% CI (1.96, 9.82), P <0.001], knee mobility[ MD =6.78, 95% CI (2.79, 10.77), P <0.001], Lysholm score[ MD =11.63, 95% CI (4.91, 18.36), P <0.001], IKDC score[ MD =7.83, 95% CI (6.09, 9.57), P <0.001] and Tegner score[ MD =0.60, 95% CI (0.31, 0.89), P <0.001] in the arthroscopic group were higher than those in the traditional incision group., Conclusion: Compared with the traditional open reduction and internal fixation, arthroscopic surgery in patients with ACL tibial avulsion fracture can shorten the operation time, hospital stay and fracture healing time, reduce the incidence of postoperative complications, and obtain good postoperative knee function. It can be recommended as one of the first choice for patients with ACL tibial avulsion fracture.

Objective: To study the expression of the human novel gene NM23-H1B in ovarian cancer., Methods: Forty-eight samples from patients with ovarian tumor at different clinical stages and 8 from normal ovaries were examined for NM23-H1B mRNA expression by using RT-PCR, northern blot and in situ hybridization., Results: All samples expressed NM23-H1B mRNA through RT-PCR, while the level of expression in ovarian tumor was higher than that of normal ovary. The level of expression in early stage (stage I and II) cancer was higher than in advanced (stage III and IV) cancer. The results of northern blot showed that NM23-H1B was over expressed in ovarian cancer while low expressed in normal ovary or low malignant potential (LMP) ovarian cancer. In early stage carcinoma, the expression level was related with the differentiation of tumor cell. Well-differentiated cancer expressed NM23-H1B mRNA at comparatively higher level. The result of in situ hybridization showed that positive expression rate of NM23-H1B mRNA in ovarian cancer (100%, 40/40) was significantly higher than that in normal ovary (0/8) or LMP ovarian cancer (2/8)., Conclusion: The novel gene NM23-H1B is related to ovarian cancer.