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Preparation of red-mud based paste-like backfill material using red mud, coal gangue, and other industrial solid wastes was accounted. In order to understand the hydration characteristics of red-mud based paste-like backfill material, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric-differential scanning calorimetry, and scanning electron microscope-energydispersive X-ray spectroscopy techniques were used to investigate the hydration products of the hardened paste, which was formed after hydration of raw materials. The results show that the most optimized proportion is the number E03 experiment, in which the mass ratio of cementing material, red mud, coal gangue, and additive agent is 1:16:5:11, the solid mass fraction is 70%, and the uniaxial compressive strength after 28 days is 5.49 MPa. The hydration products of red-mud based paste-like backfill material are mainly gismondine (CaAl2 Si2O8·4H2O) and ettringite (AFt). As the hydration reaction proceeds, the quantity of hydration products increases significantly. Needle-shaped ettringite forms during the early hydration period and gradually transforms into rod-shaped ettringite; this transformation is helpful in the strength development of the red-mud based paste-like backfill material.

An experiment was conducted to determine the difference between using biomass pine sawdust and pulverized coal in the reduction roasting of high-iron Bayer process red mud from the perspective of reduction temperature, reduction time, and reducing agent dosage. Experimental results show that biomass pine sawdust reduction roasting is quicker, occurs at a lower temperature, and is a superior process to pulverized coal reduction roasting. The mechanism of using biomass pine sawdust in reduction roasting of high-iron Bayer process red mud at a low temperature was investigated using thermal analysis, X-ray diffraction, and dynamic analysis. In addition, the optimum conditions involved in reducing high-iron Bayer process red mud were determined using biomass pine sawdust at medium and low temperatures. It is found that when using 20% biomass pine sawdust in mass at a reduction temperature of 650℃ and a reduction time of 30 min, the high-iron red mud in the Bayer process can be completely magnetized. A thermogravimetric experiment conducted on biomass pine sawdust indicates that the main stage of sawdust pyrolysis occurs within a temperature range of 250-375℃. The pyrolysis rate reaches a maximum at about 350℃, but tends to be gentle at 450℃. The main stage of pulverized coal pyrolysis occurs at 300-700℃; the pyrolysis rate is at its maximum at 450℃ but it tends to be gentle at 650℃. The kinetic study shows that at a temperature of 300-400℃, the apparent pyrolysis activation energy of the sawdust is much lower than that of pulverized coal, indicating that sawdust is more prone to pyrolysis than pulverized coal at this temperature range. In summary, biomass reduces high-iron Bayer red mud at a lower temperature, which is about 200℃ lower than that of coal-based reduction.

ABTEM was presented, an availability based trust model, and many availability oriented security service can be obtained based on this model. The performance results show that malicious nodes can be successfully discovered in accordance with its malicious acts in the routing layer when apply ABTEM on the DSR protocol. Furthermore malicious nodes can be isolated to protect the network from the attack of them, and which will significantly increases system avail- ability.

Heterakis gallinarum is one of the common parasitic nematodes found in the caecum of poultry. To investigate the genetic diversity and genetic structure of the H. gallinarum population in Sichuan, we amplified and sequenced the complete mitochondrial (mt) cytochrome c oxidase subunit II (cox2) gene of 59 H. gallinarum isolates from seven different geographical regions, then analyzed their genetic polymorphisms. All cox2 genes of the 59 H. gallinarum isolates were 696 bp in length, with an average A + T content of 67.1%. Fifty-nine sequences contained 34 variable sites, and were classified into 23 haplotypes (HS1-HS23). The values of haplotype diversity (Hd) and nucleotide diversity (π) were 0.688 and 0.00288, respectively. Based on values of FST and Nm (FST = 0.01929, Nm = 12.71), there was a frequent gene flow but no significant genetic differentiation observed among the populations. The network map showed that the most prominent haplotype was HS1, and the other haplotypes (HS2-HS23) were centered on HS1 with a star-like topology, indicating that H. gallinarum had previously experienced a population expansion. To our knowledge, this is the first research on the population genetics of H. gallinarum based on mitochondrial cox2. [ABSTRACT FROM AUTHOR]

Objective: To compare clinical efficacy between anatomical locking plate (ALP) and ordinary steel plate (OSP) in treating closed calcaneal fractures with SandersⅡ and Ⅲ., Methods: From May 2016 to May 2018, 68 patients with closed Sanders typeⅡ and Ⅲ calcaneal fractures were retrospectively analyzed, and were divided into anatomical locking plate group (ALP group) and ordinary steel plate group (OSP group) according to two kinds of plate fixation, and 34 patients in each group. In ALP group, there were 21 males and 13 females aged from 20 to 63 years old with average of (35.16±8.45) years old; 14 patients were typeⅡand 20 patients were type Ⅲaccording to Sanders classification;treated with ALP. In OSP group, there were 20 males and 14 females aged from 19 to 63 years old with average of (35.05±8.39) years old;19 patients were typeⅡand 15 patients were type Ⅲ according to Sanders classification;treated with OSP. Operative time, intraoperative blood loss and complications between two groups were observed and compared;preoperative and postoperative Böhler angle and gissane angle were also compared;American Orthopaedic Foot & Ankle Society (AOFAS) ankle and hind foot scores, foot and ankle disability index (FADI) scores were applied to evaluate clinical effect., Results: All patients were followed up from 11 to 14 months with an average of (12.06±0.81) months. There were no statistical differences in opertive time, intraoperative blood loss, incision infection and refracture rate in complications between two groups ( P >0.05);while there was significant difference in the number of screw loosening ( P <0.05). Böhler angle and Gissane angle in ALP group at 6 and 12 months after opertaion were higher than that of OSP group ( P <0.05), and the degree of improvement of Böhler angle and Gissane angle in ALP group were also higher than that of OSP group ( P <0.05). Postopertaive AOFAS score and FADI score at 6 and 12 months in ALP group were higher than that of OSP group ( P <0.05), while no statistical difference in AOFAS grading between two groups( P >0.05)., Conclusion: Compared with OSP, ALP in treating SandersⅡ and Ⅲ calcaneal fractures could achieve better therapeutic effect, avoid screw loosening, reduce complications, and improve limb function in further.

Heterakis gallinarum is one of the common parasitic nematodes found in the caecum of poultry. To investigate the genetic diversity and genetic structure of the H. gallinarum population in Sichuan, we amplified and sequenced the complete mitochondrial (mt) cytochrome c oxidase subunit II (cox2) gene of 59 H. gallinarum isolates from seven different geographical regions, then analyzed their genetic polymorphisms. All cox2 genes of the 59 H. gallinarum isolates were 696 bp in length, with an average A + T content of 67.1%. Fifty-nine sequences contained 34 variable sites, and were classified into 23 haplotypes (HS1-HS23). The values of haplotype diversity (Hd) and nucleotide diversity (π) were 0.688 and 0.00288, respectively. Based on values of F ST and Nm (F ST  = 0.01929, Nm = 12.71), there was a frequent gene flow but no significant genetic differentiation observed among the populations. The network map showed that the most prominent haplotype was HS1, and the other haplotypes (HS2-HS23) were centered on HS1 with a star-like topology, indicating that H. gallinarum had previously experienced a population expansion. To our knowledge, this is the first research on the population genetics of H. gallinarum based on mitochondrial cox2.

Objective: To analysis and compare the clinical characteristics of Colles fractures between patients with osteoporotic and without osteoporotic., Methods: From June 2007 to June 2009, 260 patients with Colles fracture were reviewed, including 60 males and 200 females, with a mean age of 66.5 years old. According to Cooney classification: 44 patients were type I, 83 patients were type II, 92 patients were type III and 41 patients were type IV. Among the patients, 96 patients were osteoporotic Colles fractures, and 164 patients without osteoporotic. The general information, invalidiation rate and short-term clinical results were compared between two groups., Results: There were no statistically difference of age, gender and fracture position between the two groups. There were more patients with type III and type IV, and higher invalidiation rate in osteoporotic Colles fracture group compared to those of no osteoporotic Colles fracture group (P<0.01). At the 6 months after treatment, the clinical effects of no osteoporotic Colles fracture group was better than that of osteoporotic Colles fracture group (P<0.01)., Conclusion: The senile-osteoporotic Colles fracture has different clinical characteristics, which should be given special treatment, frequent review and communication between doctors and patients during the period of treatment.

Objective: To investigate the clinical effects and safety of vertebroplasty and kyphoplasty for the senile osteoporotic vertebral compression fractures., Methods: From December 2004 to June 2008, 28 patients (40 vertebrae) with osteoporotic vertebral compression fractures were treated with percutaneous vertebroplasty (PVP group), there were 11 males (14 vertebrae) and 17 females (26 vertebrae), with an average age of 72 years (ranged, 70 to 91 years). The fracture site of vertebral body was from T5 to L5. Other 31 patients (43 vertebrae) were treated with percutaneous kyphoplasty (PKP group), there were 13 males (18 vertebrae) and 18 females (25 vertebrae), with an average age of 74 years (ranged, 70 to 92 years). The fracture site of vertebral body was from T4 to L5. Theapeutic effects of all the patients were observed after operation, the item included visual analog scale (VAS), Oswestry score, Cobb angle, the height of anterior and middle column vertebra, and the incidence of cement leakage., Results: There was significant decrease in VAS score and Oswestry score after operation in both groups, there was significant difference between preoperative and postoperative (P < 0.01). There was no significant difference in VAS score and Oswestry score between two groups (P > 0.05). There was no significant difference in Cobb angles and the height of anterior and middle column vertebra between two groups before and after operation (P > 0.05). Among them, there were 3 vertebrae cement leakage in PVP group (7.5%) and 2 in PKP group (4.7%), but no clinical sympton occurred. There was no significant difference in the incidence of cement leakage between two groups (P > 0.05)., Conclusion: Vertebroplasty and kyphoplasty are safe and effective methods in treating senile osteoporotic vertebral compression fractures, which can restore the height of fractured vertebra, relieve pain and improve function as well as minimize the incidence of cement leakage.