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Background: To investigate the differences in microbial colony distribution in different parts of a healthy oral cavity. Methods: We assessed four sites and two methods for sampling the bacterial community of healthy individuals, and identified the colonization of bacteria on the tooth surface and buccal mucosa. Specifically, we analyzed buccal mucosa (n=10) and tooth surface (n=20) samples from healthy individuals using 16S rDNA gene sequencing. Additionally, we detected bacterial signals in healthy individuals through fluorescence in situ hybridization (FISH), which targeted the bacterial 16S rDNA gene. Results: The results indicate that there are no significant differences between the buccal mucosa and tooth surfaces in normal individuals. However, when detecting disease-associated pathogens such as Enterococcus faecalis and Porphyromonas gingivalis, it is important to use different methods and specific sampling sites. The statistics suggest that although there were no significant differences in colony composition, there were differences in the abundance and distribution of colonies on the dental and buccal mucosal surfaces. Compared to right tooth sampling with a curette, the swab sampling group had higher levels of Firmicutes, while Fusobacteria and Bacteroidetes were more prevalent in the curette tissues. Conclusions: These data provide a different perspective for future investigation on healthy people’s bacterial distribution. In normal individuals, there is no difference in the bacterial composition of the oral buccal mucosa and the dental surface, differing only in abundance. Thus, the buccal mucosa can ask as a substitute for the teeth in epidemiological investigations exploring the bacterial composition of the oral cavity.

Aims Retinoic acid-inducible gene I-like receptors (RLRs) play an essential role in human innate immune, which may influence the spontaneous clearance of hepatitis B virus (HBV) infection. We aimed to investigate whether the SNPs in RLR family were associated with HBV spontaneous clearance. Methods The current study included 82 participants with spontaneous clearance, 601 asymptomatic hepatitis B surface antigen (HBsAg) carriers and 168 participants with chronic hepatitis B (CHB). Six SNPs (DDX58 rs3824456, rs3205166, DHX58 rs2074160, rs2074158, IFIH1 rs2111485, rs3747517) were genotyped to explore their association with HBV spontaneous clearance. Results Patients carrying the mutant allele C at rs3824456 or A at rs2074160 were more likely to achieve spontaneous clearance compared with asymptomatic HBsAg carriers (additive model: OR = 0.69, 95% CI = 0.49-0.97; dominant model: OR = 0.54, 95% CI = 0.31-0.95, respectively). In addition, patients carrying the mutant allele G at rs2111485 were more likely to achieve spontaneous clearance compared with CHB (dominant model: OR = 0.47, 95% CI = 0.25-0.87). The mutations were protective factors for HBV spontaneous clearance. Conclusion These results suggest the DDX58 rs3824456, DHX58 s2074160, IFIH1 rs2111485 were associated with spontaneous clearance of HBV, which may be predictive markers in the Chinese Han population of HBV. This article is protected by copyright. All rights reserved.

A visible light-induced decarboxylative Chichibabin pyridinium synthesis between α-amino acids and aldehydes was developed. When the in situ generated α-enamine acids were photoexcited, they were oxidized by aerobic oxygen to give radical cation species. After decarboxylation and further oxidation, the generated iminium undergoes Chichibabin cyclization to afford pyridiniums. This photochemical protocol enables the synthesis of various tetra-substituted pyridiniums and related natural products in one-step.

To analyze the rollover safety, finite element models were established for the electric bus body frame, rollover simulation platform, living space, and bus rollover. The strength and stiffness of the body frame were calculated under four typical working conditions considering the main low-order elastic modal characteristics. The results indicate that the initial body frame of the electric bus satisfies the required structural strength, stiffness, modes, and rollover safety, and it has great potential for lightweight design. Sensitivity and structural contribution analyses were performed to determine the design variables for lightweight optimization of the body frame, and a mathematical model was established for multi-objective collaborative optimization design of the electric bus. Then, the radial basis function neural network was used to approximate the optimization model. Besides, the accuracy of the approximate model was verified, and the non-dominated sorting genetic algorithm II was employed to determine solutions for the lightweight optimization. Compared with the initial model, the mass of the optimized model is reduced by 240 kg (9.0%) without any changes in the materials of the body frame.

The spiroindoline skeleton featured with 2,7-diazaspiro[4.4]nonane exists in various structurally intricate and biologically active monoterpene indole alkaloids. A catalytic asymmetric cascade enamine isomerization/spirocyclization/dearomatization succession to construct the spiroindoline was developed, which employed the indolyl dihydropyridine as a substrate under catalysis of the chiral phosphoric acid. This cascade reaction provided various spiroindolines in both diastereoselective and enantionselective fashions.

A process for the α-carboxyalkylation of tryptophols and tryptamines by the functionalization of C-H bonds under visible light irradiation has been developed. The photochemical strategy activated the C-Br bonds of α-bromo-alkylcarboxylic esters to provide carbon-centered radicals under the catalysis of Ir(iii) photocatalyst and coupled with indole derivatives. This methodology displayed wide functional group tolerance and excellent regioselectivity, and was applied to the late-stage functionalization and preparation of indole-containing hybrids.

Background: Closed reduction of pediatric femoral shaft fractures is one of the most difficult types of partial fracture reductions. Open reduction increases the harm to children. Although smaller invasive open reduction is mostly used at present, it has an impact on the microenvironment around the fracture and results in increased intraoperative bleeding, an increased risk of postoperative infection and surgical scarring, which has a great psychological impact on children. Methods: Given the above challenges, we propose another intraoperative reduction method. The technique described involves closed reduction and internal fixation for pediatric femoral shaft fractures using a new type of intraoperative fixator. Result: This technique brings hope that the success rate of closed reduction for pediatric femoral shaft fractures can reach 100%. Conclution: The method is demonstrated in a patient.

Objective The treatment of missed Monteggia fracture remains a challenge, despite the various surgical methods described. The purpose of this study was to explore a new surgical technique utilizing external fixator-assisted ulnar osteotomy and to assess the surgical results in a case series. Methods Thirteen patients with missed Monteggia fractures were treated at our institution using this new surgical technique from August 2012 to January 2016. Our series included 11 boys and 2 girls. The left elbow was involved in 6 patients and the right elbow was involved in 7 patients. According to the Bado classification, 10 fractures were classified as Bado type I with anterior radial head dislocation and 3 were classified as Bado type III with anterolateral dislocation. The average age at the time of surgery was 5 years 8 months (range, 2 years 2 months-10 years). The mean trauma-to-surgery interval was 12 months (range, 2-36 months). All patients underwent ulnar osteotomy with angulation and lengthening using a temporary external fixator, plate fixation of the osteotomy, and open reduction of the radial head dislocation without annular ligament reconstruction. Results The average follow-up was 27 months (range, 16-44 months). The average operation time was 175 min (range, 140-215 min). The average length of distraction was 0.7 cm (range, 0.5-1.2 cm) and the average angulation was 28° (range, 20°-30°) at the ulnar osteotomy site intraoperatively. The elbow performance score (Kim's) was excellent in 10 cases and good in 3 cases. No neurovascular complications, compartment syndrome or implant breakage occurred. No pain in the distal radioulnar joint or limited range of motion of the wrist occurred in any patient. The radial head remained reduced in all patients with no subluxation or redislocation. However, delayed ulnar union occurred in 3 cases, all of which were successfully treated with plaster cast immobilization within approximately 6 months postoperatively. One patient presented with cubitus valgus postoperatively with a carrying angle of 30°, which was 10° greater than the contralateral carrying angle. Conclusions External fixator-assisted ulnar osteotomy offers substantial flexibility for achieving the optimal positioning of the transected ulna to reduce the radial head prior to the final ulnar osteotomy fixation with a plate, thereby facilitating an effective operative performance. Our procedure is a safe and effective method to treat missed pediatric Monteggia fractures.

A research method for multi-echelon inventory allocation of civil aircraft spare parts with lateral transshipments and maintenance ratio is proposed in this paper, and the maintenance rate is considered into the inventory model, aiming at the problem of multi-echelon inventory allocation with lateral transshipments for civil aircraft spare parts. Firstly, the principle of the multi-echelon inventory model with lateral transshipments and maintenance ratio is proposed. Then, by considering the fleet availability and the satisfaction ratio as the constraints, a mathematical model is built with the inventory system total cost as the optimization objective. Secondly, the procedure of solving multi-echelon inventory allocation model considering the influence of lateral transshipments and maintenance ratio is discussed based on the marginal analysis method. Finally, some components of Boeing 737 are selected as the research objects, the multi-echelon inventory allocation is investigated by considering lateral transshipments and maintenance ratio. The analysis results in this paper show the best number of multi echelon inventory allocation, the minimum inventory system total cost and the fleet availability are 1.205 million dollars and 0.9909 respectively. Comparing the traditional inventory model without considering lateral transshipments and maintenance ratio, and the model which only considers the maintenance ratio, the results indicate that the model offered in this paper could reduce the total cost of inventory system significantly, and provides theoretical support and method guidance for the accurate allocation of multi echelon inventory optimization for civil aircraft spare parts.

The real-time phase tracking has a large number of applications in the precise measurement of various physical parameters. The classical limit of fiber phase tracking has been realized with homodyne detection under a low photon flux (typically ~ 106 s−1). However, it is still difficult to approach the coherent state limit when measuring a weak phase fluctuation in real time by using a larger photon flux. In this work, we propose a fiber Mach–Zehnder system and experimentally demonstrate a nearly quantum-limited phase tracking with mean photon numbers of $$\sim3.7 \times 10^{10}$$ s−1. In the experiment, the input state is a continuous-mode coherent state and an adaptive Kalman filter is used to construct a phase-locked loop. We effectively track a very weak random phase varying between − 0.07 and + 0.07 radians, and the minimum mean-squared error is optimized to $$2.5 \times 10^{ - 5}$$ which approaches the coherent state limit. Our method has potentially applications for fiber-based real-time sensing and measurements.

PurposeThe primary aim of our study was to evaluate the comparative efficacy and safety profile of curettage and mixed bone grafting without instrument or with elastic intramedullary nailing in the treatment of humeral bone cyst in children.MethodsOur retrospective study included a total of 48 children harboring humeral bone cyst in our hospital from August 2012 to February 2019. The patients enrolled were divided into elastic nailing group with the application of elastic intramedullary nailing (n= 25) and control group without using instrument (n= 23) during the management of curettage and mixed bone grafting. The following medical outcomes of the two groups were monitored and recorded: the amount of intraoperative blood loss, operation time and postoperative full weight-bearing time, in addition to postoperative clinical effects after 1 year, the function and pain level of shoulder joint before and 1, 3, 6, 9, 12, and 16 months after operation. Follow-up radiographic outcomes were reviewed to observe bone healing, local recurrence and internal fixation loosening, and other postoperative complications.ResultsThe clinical curative effect of the elastic nailing group was higher than that of the control group 16 months after operation (96.00% > 73.91%,P< 0.05). The intraoperative blood loss and postoperative full weight-bearing time in the elastic nailing group were less than those in the control group (P< 0.05), but the operation time was statistically insignificant between the two groups (P> 0.05). Before operation, the shoulder joint function of the two groups was comparable (P> 0.05), while the function showed remarkably better outcome in the elastic nailing group than control group 1 to 16 months after operation (P< 0.05). Before operation, the pain level of the two groups was comparable (P> 0.05), while 1 to 16 months after operation, the pain level of the elastic nailing group was significantly lower than that of the control group (P< 0.05). Patients in both groups were followed up for 16 months. Mixed bone grafting fusion was indicated by imaging CT and X-ray during the follow-up period, with an average fusion time of 11.3 ± 1.2 months (range, 8–16 months). Three months after operation, there was 1 case of incomplete pathological fracture in the control group, while no related complications occurred in the elastic nailing group. Moreover, no tumor recurrence was observed in the two groups. The two groups were comparable in terms of the incidence of complications (P> 0.05).ConclusionChildren with humeral cyst treated with curettage and mixed bone grafting with the additional use of elastic intramedullary nailing exerted superior results to those without using instrument as there are beneficial outcomes and safety profile and no complications.

A visible light-induced decarboxylative Chichibabin pyridinium synthesis between α-amino acids and aldehydes was developed. When the in situ generated α-enamine acids were photoexcited, they were oxidized by aerobic oxygen to give radical cation species. After decarboxylation and further oxidation, the generated iminium undergoes Chichibabin cyclization to afford pyridiniums. This photochemical protocol enables the synthesis of various tetra-substituted pyridiniums and related natural products in one-step.

BackgroundPhosphatidylinositol-4-phosphate-binding protein GOLPH3L is overexpressed in human ductal carcinoma of the breast, and its expression levels correlate with the prognosis of breast cancer patients. However, the roles of GOLPH3L in breast tumorigenesis remain unclear.MethodsWe assessed the expression and biological function of GOLPH3L in breast cancer by combining bioinformatic prediction, metabolomics analysis and RNA-seq to determine the GOLPH3L-related pathways involved in tumorigenesis. Dual-luciferase reporter assay and coimmunoprecipitation (Co-IP) were used to explore the expression regulation mechanism of GOLPH3L.ResultsWe demonstrated that knockdown of GOLPH3L in human breast cancer cells significantly suppressed their proliferation, survival, and migration and suppressed tumor growth in vivo, while overexpression of GOLPH3L promoted aggressive tumorigenic activities. We found that miRNA-1185-2-3p, the expression of which is decreased in human breast cancers and is inversely correlated with the prognosis of breast cancer patients, is directly involved in suppressing the expression of GOLPH3L. Metabolomics microarray analysis and transcriptome sequencing analysis revealed that GOLPH3L promotes central carbon metabolism in breast cancer by stabilizing the p53 suppressor SERPINE1.ConclusionsIn summary, we discovered a miRNA-GOLPH3L-SERPINE1 pathway that plays important roles in the metabolism of breast cancer and provides new therapeutic targets for human breast cancer.

Developing novel functional materials with promising desired properties in enhancing energy conversion and lowering the catalytic reaction barriers is essential for the demand to solve the increasingly severe energy and environmental crisis nowadays. Metal oxide semiconductors (MOS) are widely used in the field of catalysis because of its excellent catalytic characteristics. Introduction of defects, in addition to the adjustment of composition and atomic arrangement in the materials can effectively improve the materials' catalytic performance. Especially, introducing oxygen vacancies (OVs) into the lattice structure of MOS has been developed as a facile route to improve MOS's optical and electronic transmission characteristics. And a large number of metal oxides with rich OVs have been served in oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO2-RR) photo-degradation of organic pollutants, etc. This small review briefly outlines some preparation techniques to introduce OVs into MOS, and the characterization techniques to identify and quantify the OVs in MOS. The applications of OVs contained MOS especially in energy and environmental catalysis areas are also discussed. The effects of OVs types and concentrations on the catalytic performances are deliberated. Finally, the defective structure-catalytic property relationship is highlighted, and the future status and opportunities of MOS containing OVs in the catalytic field are suggested.

To evaluate the effects of respiratory muscle training in a population of stroke patients.The following databases were searched for clinical trials through December 2019: PubMed, EMBASE, Cochrane Library, CINAHL, and China National Knowledge Infrastructure.Randomized controlled trials (N=9) published in English met the inclusion criteria.Data were extracted and assessed for accuracy by 2 reviewers. Any disagreements were resolved after discussions with an independent third reviewer. The quality of the included randomized controlled trials was assessed using the Cochrane bias tool.The meta-analysis showed increased maximal inspiratory pressure (standardized mean difference [SMD], 0.88; 95% confidence interval [CI], 0.62-1.15; P.001; 12-wk follow-up period: SMD, 0.94; 95% CI, 0.42-1.45; P.001), maximal expiratory pressure (SMD, 0.83; 95% CI, 0.15-1.52; P=.017; 12-wk follow-up period: SMD, 0.99; 95% CI, 0.47-1.51; P.001), forced expiratory volume in 1 second (SMD, 1.41; 95% CI, 0.57-2.24; P=.001), forced vital capacity (SMD, 1.36; 95% CI, 0.55-2.16; P.001), peak expiratory flow (SMD, 0.74; 95% CI, 0.16-1.32; P=.013), 6-minute walk test (SMD, 0.67; 95% CI, 0.11-1.23; P=.020), and decreased respiratory complications (odds ratio, 0.55; 95% CI, 0.30-1.00; P=.050) compared with no respiratory intervention or a sham intervention.Respiratory muscle training improved poststroke muscle strength and the benefits were carried over for up to 12 weeks, including improved lung function, walking capacity, and a reduced risk of respiratory impediments.

A multi-echelon inventory allocation technique with maintenance ratio for civil aircraft spare parts was proposed in this paper. Multi-echelon inventory allocation model was established, which integrates maintenance rate into METRIC (Multi-echelon technique for recoverable item control) model, and then marginal analysis method was applied to solve this model and accomplish multi-echelon inventory allocation of spare parts. Firstly, the theory of multi-echelon inventory allocation model with maintenance ratio was elaborated, and the mathematical model was established with the fleet availability as the optimization objective, the cost and the safeguard probability as the constraints. Secondly, the procedure of solving multi-echelon inventory allocation model considering the influence of maintenance ratio is discussed based on the marginal analysis method. Thirdly, landing gear LRU (Line repairable units) of a typical civil aircraft were selected as the research object, multi-echelon inventory allocation was investigated by considering maintenance ratio. The analysis results show that the minimum safeguard cost and fleet availability are respectively 2759833 dollars and 0.9806, and the number of LRU of multi echelon inventory allocation are obtained under the condition of satisfying the constrained optimization. The feasibility and effectiveness of the developed method are verified by comparing the traditional analysis method. This paper provides guidance for the accurate allocation of multi echelon inventory optimization for maintenance resources on the premise of reasonable cost reduction.

Metal oxide Semiconductors with porous hollow heterostructures can provide significant advantages for gas sensing by facilitating the increase of free electron density and the diffusion of target gases. Herein, mesoporous hollow Zn2SnO4/SnO2 microboxes were successfully synthesized by using a facile ZnSn(OH)6-sacrificial template method. In synergy with the special mesoporous hollow structure and the n-n heterojunction formed between Zn2SnO4 and SnO2, the Zn2SnO4/SnO2 composites exhibited excellent acetone-sensing properties. Compared with the pure SnO2 sensor, the Zn2SnO4/SnO2 sensor not only displayed a 2 times higher response (20.1) toward 100 ppm acetone as well as excellent selectivity and stability at the optimal operating temperature of 250 °C, but still maintained a perceived response (2.4) even when the concentration of acetone was down to 1 ppm. In addition, the enhanced sensing mechanism of Zn2SnO4/SnO2 microboxes was also discussed in detail. This work indicates that the mesoporous hollow Zn2SnO4/SnO2 microboxes can be very promising sensing material for the application of acetone gas sensors.

This paper proposes a research method for multi-echelon inventory allocation of civil aircraft spare parts with lateral transshipments and importance degree to investigate the influence of importance degree on inventory allocation of spare parts. Firstly, the procedure of multi-echelon inventory optimal allocation for civil aircraft spare parts is elaborated under considering importance degree and lateral transshipments. Secondly, the inventory optimal model with the fleet availability as the objective function, inventory system total cost and the fill rate as the constraints are constructed. Thirdly, the marginal analysis method is applied to resolve the mathematical model. Lastly, the spare parts of civil aircraft door are selected as the study object, and the inventory optimal allocation is investigated. The analysis results illustrate the optimal configuration quantity for each spare part, and the inventory system total cost and fleet availability are obtained under the condition of satisfying the constraints. Through the comparison of the results of the normal lateral transshipments model, the multi-echelon inventory allocation of civil aircraft spare parts with lateral transshipments and importance degree is validated to be feasible and effective.

The traditional optimization approach for the level of repair analysis (LORA) of civil aircraft and inventory system allocation is to optimize repair level and spare parts allocation separately. But the joint cost of maintenance and inventory allocation policy will not be the necessarily optimal, due to the fact that the direct effect on the inventory system is neglected in the LORA process. Thus, in this paper, a joint optimization model for LORA and civil aircraft inventory system is constructed with the system total cost as the objective function and the fleet availability as the constraint. Next, the particle swarm optimization (PSO) algorithm is applied to solve the proposed multivariable nonlinear optimization model. Finally, some components of the landing gear system are selected as the examples, and through the comparison with the results from traditional sequence method and iterative algorithm, the proposed method is validated to be feasible and effective.

Consumer trust has been more and more recognized as an important factor for a successful e-commerce vendor. Based on the previous research, this paper developed an extended model for analyzing the main attributes of trust of the users in China. A survey regarding the trust of e-commerce users is conducted to empirically test the model. The result shows the perceived reputation and size; the level of multi-channel integration, the system assurance, consumers' propensity to trust and experienced-based familiarity are all positively related with consumers' trust in the vendor. The findings may provide the suggestions for the vendors to consider the trustworthy by the consumers.