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Objective: To analyze the role of the metagenome next-generation sequencing (mNGS) technique in identifying and treating the pathogen of orthopedic chronic infectious diseases. Methods: The data of patients diagnosed with orthopedic chronic infectious diseases by a surgical team of the Department of Joint Surgery of the First Hospital of Jilin University from June to December 2021 were retrospectively analyzed. mNGS and pathogenic bacterial culture were performed on these patients, based on which, in combination with clinical manifestations and treatment effects, the role of mNGS in the diagnosis of pathogenic bacteria was determined. Results: All of the 12 patients had pain and swelling of the affected limb before hospitalization. Pathogenic bacteria were detected in eight patients by mNGS and in three patients by routine bacterial culture. 10 kinds of pathogenic bacteria (Staphylococcus aureus, Streptococcus dysgalactiae, Pseudomonas stutzeri, Chaetomium globosum, Acinetobacter baumannii, Prevotella copri, Staphylococcus epidermidis, Sporothrix schenckii, Pseudomonas aeruginosaand Torque teno virus) were detected by mNGS. The same bacterium was detected in two cases by both mNGS and bacterial culture. Conclusion: The mNGS technique provides an important diagnostic basis for pathogen detection in orthopedic chronic infectious diseases.

Serious accidents of gas explosion always result in massive casualties, however the propagation law of flame during gas explosion is not clear yet, though it is important for prevention and control of such accidents. This paper designs a piping gas explosion system for numerical revealing the propagation law, which is then verified experimentally.

To analyze the characteristics of clinical trials of mucosal melanoma (MM) based on WHO international clinical trial registration platform (ICTRP), in order to provide a reference for clinical translational research of mucosal melanoma.WHO ICTRP database were searched to collect MM-related clinical trials. Two reviewers independently screened items, extracted data, and descriptive analysis was performed for the included trials, including number of registrations, research phase, country/region, clinical study design, etc. RESULTS: The results showed that there were 51 registered clinical trials involving MM. European and American countries and East Asia were the main study sites, and head and neck MM were mainly investigated in East Asia (11/12). Forty-eight of them were sponsored by investigators, and only 3 were sponsored by biomedical companies. The main clinical trials were single center (42 items) and in stage II (38 items). Interventions were complex, and multiple treatments and drug therapy accounted a dominant position.In-depth analysis of clinical trials information can help to understand the current situation and development trends in the field of mucosal melanoma. The number of clinical studies of mucosal melanoma is relatively small and has not received much attention.

In order to research on gas exploration shock wave spread law via a one-way bifurcation pipeline, the gas exploration pipeline experimental system and numerical calculation model were established. By adopting the comparative analysis of experiments and numerical modeling, it conducted researches on the attenuation and shunt characteristics of the gas exploration shock wave via the one-way bifurcation pipeline and obtained the computational formulas for shock wave attenuation coefficients of branch pipelines and straight pipelines and shock wave shunt coefficients of branch pipelines. As the research result showed that when the pipeline bifurcation angle was fixed, the larger the shock wave overpressure was, the larger the overpressure attenuation coefficients of straight pipelines and branch pipelines were. When the shockwave overpressure was fixed and the one-way bifurcation pipeline angle increased, the shock wave overpressure attenuation coefficients of branch pipelines would be aggregated and the shock wave overpressure attenuation coefficients of straight pipelines would be decreased, which reflected the shunting action of the shock wave in branch pipelines and straight pipelines; the larger the branch pipeline bifurcation angle, the smaller the shunting action for straight pipelines. The research achievements in the paper had important significance for the assessment of structures damage in mine laneways gas exploration accidents and installation of the antiexploration manhole cover, which further enriched gas exploration spread theory.

The process of large-scale logistics management, logistics vehicle scheduling is the core content in logistics management process. In order to achieve optimal scheduling of vehicles, saving transportation costs, and taking into account the defect of high computational complexity exists in traditional vehicle scheduling algorithm, which is not practical for application, this paper proposes an improved vehicle scheduling optimization model. Experimental results show that the new algorithm is applied to large-scale logistics management optimization model, which can improve its practicality and effectiveness.

With the rapid development and wide application of Li-ion batteries, cathode materials containing value metals Co, Ni and Mn are blended by several kind of metal oxide presently for pursuing high safe stability and low cost. The composition of spent Li-ion batteries has become complicated and optimum leaching condition varied. In this paper, leaching process for the mixture of pure LiCoO2and Li (Ni1/3Co1/3Mn1/3)O2was studied. With an increase in component of LiCoO2in mixed materials, the optimum leaching condition varied as: temperature from 60°C to 90°C, H2O2addition amount from 0.54 to 0.75ml/g and liquid-solid ratio from 10 to 20. According to this result, a real mixed spent batteries materials was recovered by being leached in 2M H2SO4at temperature of 90°C, liquid-solid ratio 20 and 0.6ml/g H2O2added. The leaching efficiencies of Co, Ni, Mn, Li were 96.88%, 93.71%, 92.12%, 99.43% respectively. Cu, Al and Fe in solution were removed by precipitation and solvent extraction. Finally, Ni, Co, Mn were extracted by D2EHPA for separating with Na+and other impurities, which is used as a raw materials for preparation of cathode active materials in batteries.

Summary Aims Spinal cord injury (SCI) can induce excessive astrocyte activation. Hydrogen has been deemed as a novel antioxidant. We investigated whether molecular hydrogen could act as an antiastrogliosis agent during SCI and oxidative injury in experimental rats and cultured astrocytes. Methods Hydrogen-rich saline (HS, 8 mL/kg, i.p.) was injected every 12 h after SCI in rats. The expression of STAT3, p-STAT3, and glial fibrillary acidic protein (GFAP); the release of IL-1β, IL-6, and TNF-α; and astrogliosis, along with the BBB score, were evaluated. Culturing astrocytes with hydrogen-rich medium, the intracellular reactive oxygen species (ROS), astrogliosis, and the release of proinflammatory cytokines were assessed after H2O2-induced injury. Results In the HS group, the expression of STAT3, p-STAT3, and GFAP and the proinflammatory cytokines were decreased in local spinal cord on postoperation day (POD) 3; on PODs 7 and 14, reactive astrogliosis was suppressed, and the locomotor function was also improved. Furthermore, hydrogen-rich medium attenuated the intracellular production of ROS (especially HO•), astrogliosis, and the secretion of proinflammatory cytokines in astrocytes 12 h after H2O2-induced injury. Conclusions Molecular hydrogen could suppress reactive astrogliosis after contusive SCI and reduce the release of proinflammatory cytokines produced by active astrocytes related to oxidative injury. Thus, molecular hydrogen is potential to be a neuroprotective agent.

Reductive ammonia leaching method was used to recover Cu and Co from heterogenite. The influences of the reductant quantity, leaching temperature, the concentration ratio of NH3to (NH4)2SO4, leaching time and liquid-solid (L/S) ratio on leaching rate of cobalt and copper were investigated. The optimal conditions at which the leaching rate of copper and cobalt were 96.07%, 98.24% respectively and that of Fe, Mg and Al were almost 0 were as follows: time = 5 h, T = 50°C, the amount of ammonia is 1.2 times of theorrtical, C(NH3):C [(NH4)2SO4] =1:3, L/S ratio = 3:1, and the dosage of Na2SO3is 0.5 times of the heterogenites mass.

Osteoblasts play a crucial role in bone formation. However, the molecular mechanisms involved in osteoblast differentiation remain largely unclear. Runt-related gene 2 (Runx2) is a master transcriptional factor for osteoblast differentiation. Here we reported that p300/CBP-associated factor (PCAF) directly binds to Runx2 and acetylates Runx2, leading to an increase in its transcriptional activity. Upregulation of PCAF in MC3T3-E1 cells increases the expression of osteogenic marker genes including alkaline phosphatase (ALP), osteocalcin (Ocn), and Osteopontin (Opn), and ALP activity was stimulated as well. Consequently, the mineralization of MC3T3-E1 cells was remarkably improved by PCAF. In contrast, PCAF knockdown decreases the mRNA levels of ALP, Ocn, and Opn. ALP activity and the mineralized area were attenuated under PCAF knockdown conditions. These results indicate that PCAF is an important regulator for promoting osteoblast differentiation via acetylation modification of Runx2.

Kinetics of Co(II) extraction from sulfate aqueous solution by the sodium salt of di-decylphosphinic acid (Na-DDPA) was studied using a modified Lewis cell to disclose the mechanism of extraction. Parameters affecting the extraction rate, such as stirring speed, temperature, interfacial area, Na-DDPA concentration and Co(II) concentration, were investigated, respectively. The effect of diffusion resistance on extraction rate was negligible when the stirring operation was conducted in a plateau region of 95-110 r/min. Extraction rate increased with the increase in the temperature or specific interfacial area. The activation energy E was calculated to be 32.75 kJ/mol. These suggested that rate controlling mechanism of Co(II) extraction by Na-DDPA was chemical reaction regime and the rate-determining step of Co(II) extraction was chemical reaction at the interface. The initial extraction rate also increased with the increase in the concentrations of Na-DDPA and Co(II). The extraction rate equation and mechanism of Co(II) extraction by Na-DDPA were proposed.

Three kinds of dialkylphosphinic acids (DAPAs), i.e. dihexylphophinic acid (DHPA), di-(2,4,4-trimethylpentyl) phosphinic acid (DTMPPA) and didecylphophinic acid (DDPA), were synthesized through free radical addition reaction. The influence of the types of initiator, reation time and reaction temperature on the yield of DAPAs were investigated. The products were characterized by NMR and MS. By using DHPA, DTMPPA and DDPA (10% in kerosene) as extractants, the extraction of Co 2+ and Ni 2+ in sulphate medium at different equilibrium pH values were measured. The results show that the maximum yield of DHPA, DTMPPA and DDPA can all be achieved at about 130 °C under the initiation of di-tert-butyl peroxide (DTBP). All the extraction of cobalt with respect to DHPA, DDPA and DTMPPA precedes that of nickel. The difference in pH 1/2 value (defined as the pH at which 50% metal extraction occurs) between cobalt and nickel increases in the following sequence from large to small: DHPA, DDPA and DTMPPA, which indicates that the separation ability for cobalt and nickel ascends from DHPA, DDPA to DTMPPA.

A microemulsion-mediated hydrothermal method for synthesis of YVO4:RE (RE=Yb3+/Er3+, Yb3+/Tm3+) nanoparticles by hydrothermal treatment of quaternary microemulsion medium consisting of Na3VO4/NaOH and RE(NO3)3 aqueous solution, surfactant cetyltrimethylammonium bromide (CTAB), cosurfactant n-hexanol and oil phase n-heptane was report. The confinement of microemulsion droplets acting as microreactors during the reaction process allows the formation of small size YVO4:RE nanoparticles with relatively narrow size distribution and less aggregation. The structure, size and shape of YVO4:RE nanoparticles were investigated by means of X-ray diffractometry (XRD) and transmission electron microscopy (TEM). Compared with the conventional solid annealing diffusion method, the microemulsion-mediated hydrothermal method shows superiority in obtaining YVO4:RE nanoparticles with controllable size, narrow size distribution and less aggregation. The microemulsion-mediated hydrothermal method may be potentially applicable for synthesis of other rare earth doped up-converting luminescence nanomaterials.

Simultaneous recovery of rare earth, nickel and cobalt resources from the anode material of hydrogen-nickel battery was performed through a hydrometallurgical process. Most of rare earth elements are separated from nickel and cobalt in the form of sulfates when the anode material is firstly leached with sulfuric acid. Then, the precipitated rare earth sulfates are dissolved with sodium hydroxide to form rare earth hydroxides. The rare earth element, zinc and manganese ions in the lixivium are also separated from nickel and cobalt by using PC-88A extractant system, and the organic phase loaded rare earth is stripped with hydrochloric acid. By neutralizing the stripping solution with rare earth hydroxide, the rare earth chloride is obtained. Under the suitable leaching conditions of sulfuric acid 3 mol/L, leaching time 4 h and temperature 95 ℃, 94.5% of rare earth in the anode material is transformed into the sulfate precipitates, and the leaching ratios of nickel and cobalt can approach 99.5%. When the pH value of the extractive system is controlled in the range of 3.0-3.5, the rare earth elements in the lixivium can be extracted completely into the organic phase and the stripping recovery of the rare earth can reach 98% in the extraction stage. The total recoveries of rare earth, nickel and cobalt are 98.9%, 98.4% and 98.5%, respectively.

Fine nickel(Ni) powders with controllable particle sizes were synthesized via the reduction of nickel hydrazine complex precursors of pure [Ni(N 2 H 4 ) 2 ]Cl 2 and a mixture of [Ni(N 2 H 4 ) 2 ]Cl 2 and [Ni(N 2 H 4 ) 3 ]Cl 2 in aqueous solution. The mechanism of the formation of metallic Ni powders experiences the reduction of nickel hydroxide by hydrazine released from the ligand exchange reaction between nickel hydrazine complex and NaOH. In comparison with the method of preparing Ni powders from nickel salts, the method of making Ni powders via the reduction of nickel hydrazine complex precursors shows the advantages of using half dosage of hydrazine for complete reduction of nickel ions in solution, and the obtained Ni particles show less agglomeration and better dispersibility. Moreover, the average particle size of nickel powders can be controlled from 180 to 260 nm by adjusting the reaction molar ratio and concentration.

The observation of efficient blue, green, orange and red luminescence from CdS nanocrystals made by using a reverse micelle method was reported. The blue luminescence about 480 nm is attributed to the radiative recombination of electron-hole pairs. The red luminescence around 650 nm is due to the radiative recombination of the exciton trapped in the nanocrystal surface defect states. The combination of different portion of band-edge emission and surface trap state emission results in green and orange luminescence for the nanocrystals. The CdS nanocrystals with efficient multicolored luminescence may find potential application in full color displays and biolabelings.

Nanocrystalline tin oxide (S1) was prepared by using molten boric acid as a flux and was characterized by XRD, TEM, and BET analysis. Its photocatalytic activity under UV excitation was evaluated by the photodegradation of methylene blue in water and compared to that of the well-known P25 (TiO2) and SnO2 powder (S2) synthesized from hydrothermal system without the participation of H3BO3. It has been revealed that S1 exhibits similar photocatalytic activity to that of P25 powder and better than that of S2. The high photocatalytic activity of S1 is most likely to be originated from its small particle size and the boron-doping in the crystal lattice.

Tribological behavior of B4C-SiC self-mated pairs was studied, and pre-oxidation treatment was adopted to improve the tribological properties of B4C-SiC. At the same SiC content, self-friction coefficient of B4C-SiC decreases with the increase of sliding distance, normal load, and sliding velocity; while the increasing of SiC content leads to increase of both self-friction coefficient and ware rate, which was determined to be within the range of 0.8×10-6~5.8×10-6 mm3·N-1·m-1. Pre-oxidation treatment of the B4C-SiC resulted in the formation of B2O3/H3BO3 lubricant layers, which effectively reduced the self-friction coefficient.

To evaluate the effects of lentiviral vector-mediated RNA interfere gene Nogo receptor (NgR) of rat cortical neurons in repairing spinal cord injury.The recombinant-lentiviral vector with small inferring RNA siNgR199 which had been constructed was transfected into rat cortical neuron cells in vitro in 3 multiplicity of infection (MOI). The infection rate was determined with fluorescent microscope, and the target gene was detected by PCR analysis. Then, the recombinant was injected into the cortical motor area of the rats with severe spinal cord injury, and the saline was also injected into other rats with severe spinal cord injury as a match control. The functional recovery of the rats' hindlimb was assessed using BBB score and the nerve fiber of the injured region was observed by nerve tracing.The rate of recombinant infecting rat cortical neuron in vitro exceeded 99%. PCR analysis confirmed that the effect of lentiviral vector-mediated RNA interfering gene NgR of rat cortical neurons in vitro was 61%. Although all rats with spinal cord injury were observed to have the hindlimb functional recovery, these rats injected with recombinant had better hindlimb functional recovery than others showing by more BBB score (P0.01). Moreover, it was found that some nerve fiber passed the injured spinal cord region of the rats which were injected with recombinant.The recombinant lentiviral vector with siNgR199 which had been constructed is able to promote the growth of nerve fiber and the functional recovery of the rats' hindlimb.

In the present study, we examined the mechanisms of hydrogen-rich saline, a reported therapeutic antioxidant, in the treatment of acute spinal cord contusion injury. Male Sprague-Dawley rats were used to produce a standardized model of contuses spinal cord injury (125 kdyn force). Hydrogen-rich saline was injected intraperitoneally (5 ml/kg) immediately, and at 24 and 48 h after injury. All rats were sacrificed at 72 h after spinal cord injury (SCI). Apoptotic cell death, oxidative stress, inflammation, level of Brain derived neurotrophic factor (BDNF) were evaluated. In addition, locomotor behavior was assessed using the Basso, Beattice and Bresnahan (BBB) scale. We observed that administration of hydrogen-rich saline decreased the number of apoptotic cells, suppressed oxidative stress, and improved locomotor functions. Hydrogen-rich saline increased the release of BDNF. In conclusion, hydrogen-rich saline reduced acute spinal cord contusion injury, possibly by reduction of oxidative stress and elevation of BDNF.

To compare the results of anterior cervical corpectomy and fusion with preserved posterior vertebral wall (PWCF) with the classical anterior cervical corpectomy with fusion (ACF).Eighty-four patients with multi-level cervical spondylosis were randomized to ACF (n = 42) or PWCF (n = 42). Postoperative JOA score were evaluated by an independent observer. Fusion rate, segmental lordosis, and disc height were assessed by radiographs at postoperative 3 months, 6 months, and 12 months. Fusion evidence was observed by CT scan.JOA score improvement was similar for both treatments. The operation time was shorter in the PWCF group than in the ACF group. The intraoperative blood loss was less in the PWCF group than in the ACF group. Fusion rate was 100% for both groups 3 months after operation. The segmental lordosis and the disc height increased were similar in both groups.Except for reduced risk, time and blood loss during the operation, PWCF is the same as for ACF procedure. Reservation of posterior vertebral wall results in more reliable fusion. But replication of the results by other team and intensive assessment still need to be carried out.