Search

In order to promote the safety of the power battery pack in high-temperature environments for electrical vehicles, a thermoelectric cooling system was designed and tested. This system utilized a self-developed pin fin assisted cooling distributor, equipped with 6 thermoelectric cooling modules, and employed circulating cooling water for heat dissipation at the hot-ends. The coefficient of performance (COP) of the thermoelectric cooling system increased rapidly with the increase of the cooling air velocity and flow rate of cooling liquid, and then stabilized. The optimal cooling air velocity and flow rate of cooling liquid were 2.5 m/s and 33.3 mL/s, respectively. The maximum COP reached 0.26. For a lithium-ion power battery pack with a storage capacity of 36 kW·h, the temperature inside the battery pack case decreased by more than 20 ℃ under different heat generation rates (50~200 W). The initial temperature of the power battery pack dropped from 68 ℃ to below 45 ℃ at a heat generation rate of 200 W, indicating that the thermoelectric cooling system designed in this study could effectively reduce the temperature inside the power battery pack and improve the safety of electrical vehicle.

Composite materials have been widely applied to the structure of high-speed flight vehicles due to their excellent performance. In hypersonic flight, the buckling and nonlinear flutter will occur in the composite panel on account of the combined action of unsteady aerodynamic load and thermal effect. In this paper, the nonlinear finite element model of the composite thin-walled structure considering thermal effect is established, and combined with the second-order loose coupling algorithm of dynamic-structure, the nonlinear aeroelastic response of composite panels at Ma∞=5 is analyzed. The influence of the direction of composite layer and tempera-ture load on the flutter characteristics of the panel is discussed. The results show that the flutter of the panel is affected by temperature load, layer direction and free stream dynamic pressure. The flutter critical dynamic pressure of the angle-ply panel is higher than that of the cross-ply panel (the increment is more than 55%). With the increase of temperature, the flutter pressure of the panels will decrease, and the maximum reduction is about 80%. While thermal buckling occurs, the flutter dynamic pressure will increase slowly. When the temperature exceeds the critical buckling temperature of the structure, the panel will have static buckling positions under subcritical conditions, and the buckling equilibrium position changes with different dynamic pressures.

Silicon nitride has high fracture toughness and compressive strength similar to human bone. It meets the basic mechanical requirements of implants and has good biocompatibility. The micrometer/nanometer morphology surface characteristics of silicon nitride give it good osteogenic activity and antibacterial properties, which are helpful to reduce the incidence of periimplant inflammation. Therefore, silicon nitride has good application potential in dental implants. In orthopedics, silicon nitride implants have been used in spine repair and joint implantation. However, there is a lack of research on silicon nitride as dental implant material. The evaluation of the osteogenic and antibacterial properties of silicon nitride bioceramics prepared using different sintering additives and sintering processes, the antibacterial properties of silicon nitride on different dominant oral pathogens, and the osteogenic activity and antibacterial properties of silicon nitride materials implanted into the jaw need to be further studied. Combined with the latest research results at home and abroad, this review discusses the application potential of silicon nitride materials in dentistry.

Objective) To investigate the effects of an infant juice canned auxiliary food on acute inflammation and antioxidant activity in young mice. (Methods) 70 mice were divided into blank group, model group, low dose group (8.697 9 g/kg), middle dose group (17.395 8 g/kg), high dose group (34.791 6 g/kg), high dose group (69.583 2 g/kg) and positive drug control group. Adopting croton oil-induced acute ear edema model in mice to evaluate the effects of juice canned supplementary food on acute inflammation in young mice; calculated the swelling rate of left ear in each group of mice except the blank group. The levels of TNF-α, IL-2, IL-6 and IL-1β in serum were detected by ELISA. HE staining was used to detect the pathological morphology of liver tissue in mice. Electronic tongue for taste analysis. The antioxidant capacity (DPPH free radical scavenging ability, *OH free radical scavenging ability of infant canned auxiliary food was determined by ultraviolet spectrophotometry. (Results) Compared with the blank group, the left ear swelling of the model group was [ABSTRACT FROM AUTHOR]

Objective Retrospective analysis of the distribution of cerebrospinal fluid (CSF) pathogens and drug sensitivity test results in hospitalized neurosurgery patients, to provide a scientific basis for rational drug use. Methods A total of 2733 CSF specimens were collected from 2653 hospitalized patients with intracranial infection for bacterial identification and drug sensitivity tests from January 2016 to June 2018. Results A total of 207 pathogenic bacteria were isolated and the positive detection rate was 7.57% (207/2733). Among them, 115 strains of Gram ⁃ negative bacilli accounted for 57.21% (115/207), including 51 strains of Acinetobacter baumannii, 23 strains of Escherichia coli, 17 strains of Pseudomonas aeruginosa, 12 strains of Klebsiella pneumoniae, 7 strains of Enterobacter and other 5 cases; 86 strains of Gram ⁃ positive cocci accounted for 41.55% (86/207), 25 strains of Coagulase ⁃ negative staphylococci, 23 strains of S taphylococcus aureus, 19 strains of Streptococcus pneumoniae, 16 strains of Enterococcus, and other 3 cases; 1 strains of Gram ⁃ positive bacterium; 5 strains of Fungi. The resistance rates of Gram ⁃ negative bacilli to penicillins and cephalosporins were over 30% . The resistance rates of Gram ⁃ positive cocci to macrolides were over 40% . Conclusions Pathogens of intracranial infection were widely distributed and the rate of drug resistance was high. The drug resistance of hospitalized patients should be closely monitored and antibiotics should be used reasonably. DOI：10.3969/j.issn.1672⁃6731.2020.05.014

Near-field 3-D imaging based on a scanning array is an important application of Synthetic Aperture Radar (SAR) 3-D imaging technology for civil use. Compared with Single-Input-Single-Output (SISO) arrays, a Multi-Input-Multi-Output (MIMO) scanning system is a special imaging method characterized by high imaging quality, high array efficiency, loose requirements for antenna spacing and low cost. In this paper, two imaging regimes, namely, MIMO-planar scanning and MIMO cylindrical scanning, are described in terms of signal models, imaging algorithms, experimental systems, and imaging results. The results show the great application potential of the imaging technology in various scenarios.

Echo simulation is a precondition for developing radar imaging systems, algorithms, and subsequent applications. Electromagnetic scattering modeling of the target is key to echo simulation. At terahertz (THz) frequencies, targets are usually of ultra-large electrical size that makes applying classical electromagnetic calculation methods unpractical. In contrast, the short wavelength makes the surface roughness of targets a factor that cannot be ignored, and this makes the traditional echo simulation methods based on point scattering hypothesis in applicable. Modeling the scattering characteristics of targets and efficiently generating its radar echoes in THz bands has become a problem that must be solved. In this paper, a hierarchical semi-deterministic modeling method is proposed. A full-wave algorithm of rough surfaces is used to calculate the scattered field of facets. Then, the scattered fields of all facets are transformed into the target coordinate system and coherently summed. Finally, the radar echo containing phase information can be obtained. Using small-scale rough models, our method is compared with the standard high-frequency numerical method, which verifies the effectiveness of the proposed method. Imaging results of a full-scale cone-shape target is presented, and the scattering model and echo generation problem of the full-scale convex targets with rough surfaces in THz bands are preliminary solved; this lays the foundation for future research on imaging regimes and algorithms.

With years of development and accumulation, a considerable amount of research has focused on micro-motion, an important auxiliary feature in radar target detection and recognition. With the recent rise of terahertz, micro-motion feature extraction in the terahertz region has increasingly highlighted its advantages. Herein, we systematically surveyed the recent research on terahertz radar micro-motion feature extraction and discussed micro-motion feature analysis, micro-motion feature extraction, and micro-motion target imaging. And then we emphatically introduced the work of our research team, including the theoretical and experimental research on micro-motion feature analysis, micro-motion feature extraction and high-resolution/high-frame micro-motion target imaging. Furthermore, we analyzed the growing trend of micro-motion feature extraction in the terahertz region, and pointed out the new technology directions worth to be studied further and the technical challenges to be solved.

Terahertz coded-aperture imaging follows the basic principles of optical coded-aperture imaging and microwave coincidence imaging and is a novel imaging technique. Herein, the wave spatial distribution or illumination pattern is usually obtained by a sub-reflector antenna. Terahertz coded-aperture imaging has some significant advantages such as a high frame rate, high resolution, and ability of forward-looking and staring imaging. To achieve simultaneous functions of aperture coding and beam scanning, we designed a terahertz coded-aperture imaging system that utilizes digital sub-reflector antenna and quasi-optical techniques. Based on this system, we deduce and simulate the influencing factors on its resolution. Then, different algorithms are applied to the imaging model in order to verify the superiority of sparse reconstruction for coded-aperture imaging. Finally, we compare the imaging results of our imaging system and that of a traditional real aperture imaging structure for the same simulation parameters. The results prove that our imaging system performs better with high resolution, small volume, and low cost. This new imaging technique can be applied to areas such as battlefield reconnaissance, security checks, anti-terrorism, and terminal guidance.

Terahertz radar has unique advantages, including large bandwidth, high resolution, Doppler sensitivity, and anti-interference; it is a significant development in the field of target detection. Herein, the history of electronic and optical terahertz radar systems is introduced, and the current situation and latest progress pertaining to these systems are reviewed. The target characteristics of terahertz radar are summarized based on its mechanism, calculation, and measurement. Moreover, the current research status of terahertz SAR, ISAR, array, and aperture encoding imaging are discussed, and the applications of terahertz radar, such as early warning detection and security anti-terrorism systems, are briefly introduced. Finally, the development direction of terahertz radar technology is forecast.

To improve the imaging accuracy of Interferometry Inverse Synthetic Aperture Radar (InISAR), in this paper, we propose a novel method based on the joint processing of dual-frequency data. First, we divide the radar echo into two parts in the fast-time domain, then we apply the conventional InISAR method to each dataset. By comparing and analyzing the imaging results of the two parts, we can identify and remove redundant and bad pixels. Using the proposed joint processing method, we obtained the InISAR imaging results of a scatter model of an airplane and calculated the Root Mean Square Error (RMSE). The simulation results show that the proposed method can effectively improve imaging accuracy with different Signal-to-Noise Ratio (SNR).

The pressure generated by the compression of the trapped oil lead to a resistance moment,which will result in a certain oil churning power losses,when the external gear pump is working. In order to determine this part of losses,a calculation method of the oil churning power losses of external gear pump is presented. The two- dimensional simulation of a certain type of external gear pump is carried out by using dynamic mesh technology of CFD software FLUENT,and the change of the oil churning power losses in a period of the trapped- oil under different revolving speed and working pressure is analyzed. The results indicate that the oil churning power losses are mainly affected by the trapped- oil pressure,and increase along with the revolving speed and working pressure,which account for 0. 43% 5. 26% of the input power.

Simplified mechanical model of FPB isolated bridges was established,the response amplitude was calculated used mode superposition method.The accuracy of results was verified by finite element simulation based on SAP2000.It was considered that the response amplitude agreed well with that of finite element simulation.Under the action of El Centro seismic wave,the results can meet engineering precision requirements basically.The response of girder and pier were mainly influenced by the isolated mode and second mode.

Objective Retrospective analysis of the distribution of cerebrospinal fluid (CSF) pathogens and drug sensitivity test results in hospitalized neurosurgery patients, to provide a scientific basis for rational drug use. Methods A total of 2733 CSF specimens were collected from 2653 hospitalized patients with intracranial infection for bacterial identification and drug sensitivity tests from January 2016 to June 2018. Results A total of 207 pathogenic bacteria were isolated and the positive detection rate was 7.57% (207/2733). Among them, 115 strains of Gram-negative bacilli accounted for 57.21% (115/207), including 51 strains of Acinetobacter baumannii, 23 strains of Escherichia coli, 17 strains of Pseudomonas aeruginosa, 12 strains of Klebsiella pneumoniae, 7 strains of Enterobacter and other 5 cases; 86 strains of Gram-positive cocci accounted for 41.55% (86/207), 25 strains of Coagulase-negative staphylococci, 23 strains of Staphylococcus aureus, 19 strains of Streptococcus pneumoniae, 16 strains of Enterococcus, and other 3 cases; 1 strains of Gram-positive bacterium; 5 strains of Fungi. The resistance rates of Gram-negative bacilli to penicillins and cephalosporins were over 30%. The resistance rates of Gram-positive cocci to macrolides were over 40%. Conclusions Pathogens of intracranial infection were widely distributed and the rate of drug resistance was high. The drug resistance of hospitalized patients should be closely monitored and antibiotics should be used reasonably. [ABSTRACT FROM AUTHOR]

As China's economic growth goes into the "new normal", the characteristics of huge investment in construction becomes increasingly important. Meanwhile, a large bidding contract mode for large public projects has been created in engineering practice. However, after signed the general contract of the project, unreasonable risk allocation before contract and risk variation after contract may lead to risk backflow to hold-up owners. Therefore, in order to identify the risk backflow path in large public projects, this paper deconstructed the "market-hierarchy" hybrid governance structure in public general contracting projects under the new situation. In this deconstruction, the owner and the general contractor are governed with contract governance, and the general contractor and area enterprises are governed with hierarchical governance. The internal and external coupling is established in the whole life cycle of large public projects under the new situation. On this basis, this paper revealed the risk backflow path of large public projects. This research expands the project governance theory and provides guidance for engineering practices. [ABSTRACT FROM AUTHOR]

[Objective] The cellulase production conditions of Trichoderma harzianum TC10-13 were optimized in order to provide technical support for its application in tobacco. [Method]The conditions of TC10-13 were optimized by single factor and orthogonal test. The best conditions of initial pH, nitrogen source, carbon source, temperature, carbon and nitrogen concentration and surfactant content were determined by cellulase activity. [Result] The optimal carbon source, nitrogen source and initial pH were straw, yeast extract and 5.0, respectively. The best orthogonal combination was 15.0 g/L straw, 2.0 g/L yeast extract, 2.0 mL/L surfactant content and 28 °C. CMCase and FPase were 15.97 and 6.38 U/mL respectively under optimal conditions. The volume of aroma and concentration were improved after the cut tobacco treated by TC10-13, but aroma quality and irritation had no significant change. [Conclusion] TC10-13 could improve the sensory quality of tobacco, hence Trichoderma harzianum TC10-13 has good prospects. [ABSTRACT FROM AUTHOR]

Because of the uncertainties of neuron model and its parameters, some control methods become cumbersome. Iterative learning control (ILC) is independent of the exact system model, therefore is suitable for control of neural network synchronization. This paper proposed PI-type iterative learning control algorithm for synchronization control of Hodgkin-Huxley (HH) neurons. Simulation of synchronization control of master and slave neurons in four cases shows that, when the control is implemented, the dynamic behavior of the controlled slave neuron can rapidly synchronize with that of the master one. The results confirm the feasibility and effectiveness of this control algorithm. [ABSTRACT FROM AUTHOR]

The article presents a study on the live vector vaccine against Eimeria tenella in chickens. Topics mentioned include result of the study wherein the bacteria had shown protective effects on the growth of broiler including the decreased of anti-coccidial index (ACI) in Bacillus Subtilis-31 E group and increased of ACI by 18.8% in casein kinase (CK1) family and the increased in CK2 by 18.8 %.

This paper investigated the underlying mechanisms of electric field (EF) on the synchronization of neural network. Based on HH neuron model, it solved the differential equations of neuron numerically by using the modified Euler method, it investigated the effects of EF on the synchronization of excitatory-inhibitory network. The DC EF weakened the trend of impairing the network synchronization, due to introducing the adaptation current and removing the inhibitory connection; the AC EF also counteracted the negative effect because of adaptation current, moreover, the synchronous activities of the network were dependent on the amplitude and frequency of the AC EF. The results can contribute to further development of EF stimulation on treatment of neurological diseases. [ABSTRACT FROM AUTHOR]

The amplitude and phase characteristics of complex radar cross section (RCS) of a metallic sphere are analyzed based on the precise solution of its back scattering. The high resolution range profile of a sphere takes on one or two peaks at different bands, while its 2D image can be typified by an arc or a point at different bands and rotation angles. A sphere should be characterized by a dispersive, migratory or point-like scattering center model under different conditions. These conclusions may provide an important reference for RCS calibration and scattering source diagnosis. [ABSTRACT FROM AUTHOR]

Objective To screen of high cariogenicity Streptococcus mutans (S. mutans) strains isolated from clinical specimens preliminary. Methods Acidogenicity, aciduricity, extracellular polysaccharicle production and adhesion of 41 strains of S. mutans isolated from clinical specimens were investigated to screen high cariogenicity S. mutans strains. Results There were different cariogenicity among 41 strains of S. mutans, in which 3 strains of S. mutans had all high ability to produce extracellular polyaaccharide, adhere to the saliva-coated hydroxyapatite, produce acid and tolerate acid, indicated there were 3 strains with high cariogenicity S. mutans strains isolated from clinical specimens. Another 3 strains of S. mutans with all low ability to produce extracellular polysaccharide, adhere to the saliva-coated hydroxyapatite, produce acid and tolerate acid indicated they were low cariogenicity S. mutans strains isolated from clinical specimens. Conclusion We may have obtained high cariogenicity S. mutans strains isolated from clinical specimens. [ABSTRACT FROM AUTHOR]

Objective To identify Streptococcus mutans (S. mutans) strains from clinical samples. Methods Plaque samples from caries-active and caries-free sites on enamel surfaces were obtained and cultivated for S. mutans isolation. Morphology, biochemistry, automatic microorganism analysis system and polymerase chain reaction using primers homologous to surface protein antigen I / II (spaP), glucosyltransferase B (gtfB) and dextranase (dexA) were used to identify S. mutans. Genotype of isolated S. mutans was determined by arbitrarily primed polymerase chain reaction. Results Forty-six strains of S. mutans were obtained from the 32 subjects and were identified as S. mutans by biochemistry, automatic microorganism analysis system and polymerase chain reaction. Five identical genotypes were found by arbitrarily primed polymerase chain reaction. Conclusion Forty-one strains of S. mutans with different genotype were obtained from clinical samples. [ABSTRACT FROM AUTHOR]

Four phenylethanoid glycosides were isolated from the 75% EtOH extract of Forsythiae Fructus by various column chromatography methods(MCI, silica gel, ODS and semi-preparative HPLC). Their structures were identified as forsythenside M(1), forsythenside K(2), forsythoside I(3) and forsythoside A(4) by physicochemical properties and extensive spectroscopic analysis(UV, 1 D and 2 D NMR, HR-ESI-MS). Among them, compound 1 was one new phenylethanoid glycoside. The in vitro cytotoxic activities of these compounds against MCF-7, A-375, SGC-7901 and B16 F10 were evaluated. The results showed that compounds 1-4 had cytotoxic activities against MCF-7, A-375, SGC-7901 and B16 F10 at 40 μmol·L~(-1).

Objective: To study the clinical efficacy and complications of Endobutton titanium plate and clavicle hook plate in the treatment of acromioclavicular dislocation., Methods: Total 48 patients with Rockwood Ⅲ to Ⅴ acromioclavicular joint dislocation from March 2015 to May 2019 were retrospectively divided into two groups according to different surgical methods. Among the patients, 23 patients were treated with Endobutton loop titanium plate fixation (observation group), including 15 males and 8 females, ranging in age from 23 to 59 years old, with an average of(36.2±8.1) years old;Rockwood type Ⅲ in 6 cases, type Ⅳ in 11 cases and type Ⅴ in 6 cases. Twenty-five patients were treated with clavicular hook plate(control group), including 17 males and 8 females, ranging in age from 22 to 54 years old, with an average of (34.7±6.4) years old; Rockwood type Ⅲ in 6 cases, type Ⅳ in 14 cases and type Ⅴ in 5 cases. The operation time, intraoperative bleeding, hospitalization time, visual analogue scale (VAS) of pain, Constant-Murley score of shoulder function and postoperative complications were compared between the two groups., Results: All the patients were followed up, and the duration ranged from 24 to 51 months, with a mean of (30.5±6.5) months. The amountof bleeding and hospitalization time in the observation group were (71.9±4.0) ml and(8.2±1.6) d respectively;and those in the control group were (97.6±13.4) ml and (12.8±1.2) d respectively. There was significant difference between the two groups ( P <0.05). There was no significant difference in operation time between the two groups( P >0.05). The VAS scores of the observation group immediately after operation and 12 months after operation were 4.00±0.39 and 1.58±0.13 respectively, which were statistically significant compared with 7.32±0.43 and 3.09±0.23 in the control group ( P <0.05). The Constant-Murley scores of shoulder function in the observation group were 59.65±0.15 and 85.97 ±0.73 immediately and 12 months after operation, which were significantly different from those in the control group 52.77±0.19 and 55.78±0.19( P <0.05). In the observation group, there were 1 case of shoulder pain and 1 case of ectopic ossification; in the control group, there were 1 case of internal fixation failure, 3 cases of acromion impact, 3 cases of shoulder pain and 3 cases of ectopic ossification. There was significant difference between the two groups ( P <0.05)., Conclusion: Compared with clavicular hook plate internal fixation in the treatment of acromioclavicular joint dislocation, Endobutton loop titanium plate internal fixation technology has the advantages of less surgical bleeding, shorter hospitalization time, less postoperative pain, good recovery of shoulder joint function and less complications.

Magnoliae Officinalis Cortex, a common Chinese medicinal in clinic, should undergo &quot;sweating&quot; process in producing area according to Chinese Pharmacopoeia, which affects its genuineness and quality. In light of the concept and research mode of quality marker(Q-marker) for decoction pieces, the active components of Magnoliae Officinalis Cortex pieces which altered significantly before and after &quot;sweating&quot; were identified in this study. The main pharmacodynamic material basis was clarified by pharmacodynamic, pharmacokinetic and drug property research, followed by the prediction of Q-markers of Magnoliae Officinalis Cortex before and after &quot;sweating&quot;, for better improving its quality standard.

Objectives: To determine the association between glycosylated hemoglobin (HbA1c) and ambulatory blood pressure or heart rate in hypertensive patients., Methods: A total of 585 patients, who performed ambulatory blood pressure monitoring (ABPM) from September 2018 to April 2019 in Xiangya Hospital, Central South University, were enrolled and assigned into 2 groups (470 in a hypertensive group and 115 in a normal group). HbA1c levels were compared. According to the HbA1c level, the hypertensive group was divided into 2 subgroups: A high HbA1c group (HbA1c≥6.1%, n =142) and a normal HbA1c group (HbA1c<6.1%, n =328). Whole basic data and ABPM parameter were compared among the groups. Pearson/Spearman correlation analysis was applied to study the association between HbA1c and BPV. Multivariate logistic regression was used to explore the influential factors for HbA1c (≥6.1%) and continuous increase of HbA1c in different hypertensive populations, respectively., Results: The hypertensive group had higher HbA1c level than the normal group [(6.1±1.3)% vs (5.1±1.7)%, P <0.05]. In hypertensive patients, nocturnal systolic blood pressure [(131.1±19.2) mmHg vs (122.5±19.2) mmHg], nocturnal systolic blood pressure load [62.5% (15.5%-100%) vs 28.6% (0-75%)], and daytime heart rate [(74.3±11.6) min -1 vs (71.2±11.4) min -1 ] of the high HbA1c group were higher than those in the normal HbA1c group (all P <0.05). Pearson/Spearman correlation analysis showed that HbA1c was positively correlated with systolic blood pressure and blood pressure load (both P <0.05). Logistic regression analysis showed that nocturnal systolic pressure load was the risk factor for the increase of HbA1c level (OR=1.025, 95% CI 1.003 to 1.048, P <0.05). Multiple linear regression showed that nocturnal systolic pressure load was still positively correlated with HbA1c in total, tertiary, and hypertensive patients without treatment (β=0.155, β=0.171, β=0.384, respectively, all P <0.05)., Conclusions: In hypertensive patients, HbA1c is positively correlated with ambulate blood pressure, blood pressure load, and heart rate, and it has no correlation with blood pressure variability, heart rate variability, or morning blood pressure.

Objective: To study the correlation and clinical value of the arc height of upper and lower endplates, the height of intervertebral space and osteophyte of posterior edge of intervertebral space in patients with cervical spondylosis., Methods: A total of 108 patients with cervical spondylosis who underwent cervical spondylosis surgery from September 2017 to September 2018 were included in the study. Including 48 males with an average age of 52 years (30 to 72) and 60 females with an average age of 54 years (37 to 79). Among them, C 2,3 of 6 cases, C 3,4 of 15 cases, C 4,5 of 32 cases, C 5,6 of 42 cases, C 6,7 of 13 cases. X-ray films of cervical spine were taken before and after operation. The images were accessed by PACS (Picture Archiving and Communication Systems) system. The lower and upper endplate arc heights (L 1 , L 2 ), intervertebral space height (L 3 ), and posterior osteophyte width (L 4 ) were measured. Spearman was used to analyze the correlation between them., Results: L 1 was negatively correlated with L 4 (r=-0.34, P <0.05), L 3 was negatively correlated with L 4 ( r =-0.36, P <0.05). L 1 was positively correlated with L 3 ( r =0.38, P <0.05), L 2 was positively correlated with L 3 ( r =0.48, P <0.05). There was no significant difference between L 1 and L 2 ( P >0.05), L 2 and L 4 ( P >0.05)., Conclusion: The arc height of the lower endplate is negatively correlated with the width of osteophyte in the posterior margin of the intervertebral space. The cervical degeneration degree can be determined by measuring the arc height of the lower endplate, which has guiding significance for the early prevention and treatment of cervical spondylosis.

Objective: To explore whether bariatric surgery can decrease the incidence of obesity-related tumors in obesity patients., Methods: Relevant studies comparing the incidence of obesity-related tumors in obesity patients between bariatric surgery and non- bariatric surgery were identified by search of PubMed, Medline, EBSCO, High Wire Press, OVID, EMbase, China hownet (CNKI) and Wanfang databases since the self-built database. In strict accordance with the standard after the screening, literature quality and extracted data were evaluated. Review manager 5.2 software was used to perform meta-analysis and sensitivity analysis. Inverted funnel chart was used to investigate the publication bias., Results: Five articles including 108 954 patients were enrolled in the analysis. Among them, 26 218 cases were bariatric surgery group, and 82 736 cases of non-surgical weight loss were the control group. Meta analysis showed that bariatric surgery could obviously decrease the incidence of postoperative obesity-related tumor(RR=0.60, 95% CI:0.45-0.80, P=0.0005). Subgroup analysis showed that cancer risk difference of obesity-related tumor in male patients was not significant between two group, while the postoperative incidence of obesity-related tumor of female patients in bariatric surgery group was significantly lower compared to those female patients in control group(RR=0.68, 95% CI:0.61-0.77, P<0.01). During follow-up of 1 to 10 years, the incidence of obesity-related tumor in bariatric surgery group was significantly lower than that in control group(P<0.05). When follow-up was more than 10 years, the incidence of obesity-related tumors was similar between two groups(P=0.70)., Conclusion: Bariatric surgery can decrease the overall risk of obesity-related cancer, especially for female patients, but with the prolongation of time, such effect of bariatric surgery is not obvious.

Objective: To investigate the impact of intestinal spasmolytic on colon polyps and adenoma detection rate during colonoscopy., Methods: Literatures related to the effect of intestinal spasmolytic on colon polyp or adenoma detection rate were retrieved from PubMed, Medline, EBSCO, High Wire Press, OVID, EMBASE, and the China National Knowledge Articles, etc. published before July 2014. Unified data were extracted by two researchers independently and organized using Jadad scale to evaluate the quality of the enrolled studies through Review manager 5.2 Meta-analysis software., Results: Six articles were enrolled with total 47,509 cases, including 16,867 cases in the scopolamine group and 30,642 cases in the placebo group. Meta analysis showed spasmolytic could increase the detective rate of polyps (OR=1.24, 95% CI:1.19-1.30), adenoma (OR=1.25, 95% CI:1.19-1.30) and high-risk adenoma (OR=1.22, 95% CI:1.16-1.29)., Conclusion: Using colonoscopy spasmolytic scopolamine can increase the detection rate of colonic polyp and adenoma.

Objective: To establish an HPLC method for determination of four flavonoids in rat plasma after oral Ecliptae Herba extract., Methods: HPLC separation was carried out in a Neocleodur 100-5 C18 column (250 mm x 4.6 mm, 5 microm) with mobile phase A (consisting of methanol-0.2% phosphoric acid = 50:50) and mobile phase B (acetonitrile)with gradient elution at the flow rate of 1.0 mL/min. The detection wavelength was 350 nm and the column temperature was maintained at 40 degrees C., Results: There were good linear relationships between concentration and peak area ratio of luteolin, apigenin, scutellarein and diosmetin in the ranges of 0.02-50 microg/mL with the recovery rates of 71.5%-90.2%., Conclusion: This method is rapid, accurate and reproducible for determination of luteolin, apigenin, scutellarein and diosmetin in rat plasma and study on pharmacokinetics of Ecliptae Herba extract.

Objective: To analyze horizontal transmission patterns of Streptococcus mutans among caries-active preschool children for early interventions of dental caries., Methods: Plaque samples obtained from 20 caries-active preschool children between 4 and 5 years of age were cultured under anaerobic conditions for isolating S. mutans, which were identified by morphological and biochemical analyses and PCR using primers homologous to the surface protein glucosyltransferase B (gtfB). The genotypes of the isolated S. mutans strains were determined by arbitrarily primed PCR (AP-PCR)., Results: Of the 200 S. mutans isolates obtained, 19 were excluded by biochemical analysis, and the remaining 181 isolates were identified as S. mutans by PCR with primers of gtfB, showing 37 different genotypes as identified by AP-PCR. Six children were found to carry S. mutans of a single genotype, 11 carried 2 genotypes, 2 had 3 genotypes, and 1 had 4 genotypes; 2 children from different classes were found to carry S. mutans of the same single genotype., Conclusion: We identified 37 genotypes of S. mutans in these caries-active preschool children, among whom horizontal transmissions of the strains were not found.

Objective: To select and identify ssDNA aptamers specific to Streptococcus mutans strains with different cariogenicity isolated from clinical specimens., Methods: Subtractive SELEX technology targeting the whole intact cells was used to screen for ssDNA aptamers specific to the clinical isolates Streptococcus mutans strains with different cariogenicity. Radioactive isotope, flow cytometry, gene cloning and sequencing, MEME online software and RNA structure analysis software were employed to analyze the first and secondary structures of the aptamers and identify the screened aptamers., Results: Detection by radioactive isotope showed sufficient pool enrichment after 9 rounds of subtractive SELEX. Flow cytometry showed that the selected aptamers H1, H16, H4, L1, L10 and H19 were capable of binding specifically with highly cariogenic Streptococcus mutans strains but not with strains with a low cariogenicity. The aptamer H19 had the strongest binding capacity to highly cariogenic Streptococcus mutans strains, with a dissociation constant of 69.45∓38.53 nmol/L., Conclusion: We have obtained the ssDNA aptamers specific to the clinical isolates of highly cariogenic Streptococcus mutans strains.

Objective: To screen of high cariogenicity Streptococcus mutans (S. mutans) strains isolated from clinical specimens preliminary., Methods: Acidogenicity, aciduricity, extracellular polysaccharide production and adhesion of 41 strains of S. mutans isolated from clinical specimens were investigated to screen high cariogenicity S. mutans strains., Results: There were different cariogenicity among 41 strains of S. mutans, in which 3 strains of S. mutans had all high ability to produce extracellular polysaccharide, adhere to the saliva-coated hydroxyapatite, produce acid and tolerate acid, indicated there were 3 strains with high cariogenicity S. mutans strains isolated from clinical specimens. Another 3 strains of S. mutans with all low ability to produce extracellular polysaccharide, adhere to the saliva-coated hydroxyapatite, produce acid and tolerate acid indicated they were low cariogenicity S. mutans strains isolated from clinical specimens., Conclusion: We may have obtained high cariogenicity S. mutans strains isolated from clinical specimens.

Objectives: To compare the sensitivity of mammogram and breast dedicated MRI in detecting ductal carcinoma in situ with microinvaion (DCIS-MI) and ductal carcinoma in situ (DCIS) lesions, and to further investigate the independent predictive factors of mammogram and MRI sensitivity., Methods: From August 2009 to November 2011, 122 consecutive confirmed breast cancer patients who had received operations were recruited for this clinical research. These patients were divided into two groups including DCIS (72 cases) and DCIS-MI (50 cases) based on pathologic reports. All the patients were female, with mean ages of 52.6 years and 54.4 years. Preoperative bilateral breast mammogram, breast dedicated MRI depictions and reports as well as histopathological reports were collected., Results: Sensitivity of MRI outstood mammogram in each subgroups: 84.7% vs. 42.4% in DCIS (χ(2) = 27.028, P = 0.000), 94.0% vs. 80.0% in DCIS-MI group (χ(2) = 4.540, P = 0.040). And further analysis showed that MRI was more sensitive to high nuclear grade DCIS and DCIS-MI lesions than low nuclear grade ones (OR = 3.471, P = 0.031)., Results: of logistic regression analysis proved microcalcification was an independent predictive factor of mammogram sensitivity (OR = 11.287, P = 0.001)., Conclusions: Sensitivity of breast dedicated MRI is superior to mammogram in detecting DCIS and DCIS-MI groups. Lesions with microcalcifiation is an independent predictive marker which meant that mammogram would achieve high detection rate in cancers presented calcification on mammogram image when compared with non-calcification. Diagnostic performance of breast MRI is less affected by clinical and pathological characteristics of the early stage breast cancer patients but further increased detection rate is observed in DCIS and DCIS-MI with high nuclear grade lesions which indicated that MRI could detect more early stage cancers with relative more aggression biological behaviour and provide these patients with early surgical interventions before possible progression to invasive breast cancers.

Objective: To investigate the function of myosin light chain kinase (MLCK) in hearing in mouse by generating inner hair cell-specific Mlck knockout mice and analyze the effect on their hearing., Methods: Cross Mlck floxed mice with IHC-Cre mice, the genotype and knockout efficiency were confirmed by PCR. We used auditory brain stem response (ABR) to evaluate mice hearing function at different frequencies., Results: Mlck knockout mice were selected by mice tail DNA genotyping and confirmed the deletion of the target gene by isolated inner hair cell DNA genotyping. Mlck-deficient mice showed impaired hearing with a rise in ABR threshold response to click and three different pure tones (8 kHz, 16 kHz, 32 kHz), and the rise was over 20 dB at high-frequency(32 kHz). Further analyses of waveforms showed that wave-I amplitudes on 60 dB SPL, 50 dB SPL and 40 dBSPL in response to tone (16 kHz) were less than control group(P < 0.05) on average, but the ratio of wave I/II and I/III were not difference (P > 0.05)., Conclusions: Mlck is successfully deleted in inner hair cell-specific Mlck knockout mice. Mlck knockout mice display a significantly higher threshold in response to click and tones, especially in high-frequencies.

Objective: To observe the effect of acupuncture of Zusanli (ST 36) on electroencephalogram (EEG) so as to probe into its law in regulating the interconnectivity of brain functional network., Methods: A total of 9 healthy young volunteer students (6 male, 3 female) participated in the present study. They were asked to take a dorsal position on a test-bed. EEG signals were acquired from 22 surface scalp electrodes (Fp1, Fp2, F7, F3, F2, F4, F8, A1, T3, C3, C2, C4, T4, A2, T5, P3, P2, P4, T6, O2, O1 and O2) fixed on the subject's head. Acupuncture stimulation was applied to the right Zusanli (ST 36) by manipulating the filiform needle with uniform reducing-reinforcing method and at a frequency of about 50 cycles/min for 2 min. Then the stimulation was stopped for 10 min, and repeated once again (needle-twirling frequency: 150 and 200 cycles/min), 3 times altogether. The acquired EEG data were analyzed by using coherence estimation method, average path length, average clustering coefficient, and the average degree of the articulation points (nodes) for analyzing the synchronization of EEG signals before, during and after acupuncture., Results: In comparison with pre-acupuncture, the coherence amplitude values of EEG-delta (1-4 Hz) and y (31-47 Hz) waves were increased significantly after acupuncture of ST 36. No significant changes were found in the amplitude values of EEG-theta (5-8 Hz), -alpha (9-13 Hz) and-beta (14-30 Hz) waves after acupuncture stimulation. During and after acupuncture, the synchronism values of EEG-delta waves of different leads and numbers of interconnectivity between every two brain functional regions in majority of the 9 volunteers were increased clearly. In all volunteers, the degree values of all nodes except A1 and A2, the average clustering coefficients along with the increase of the threshold (r), and the average path lengths of the brain functional network of EEG-delta waves during and after acupuncture were also increased evidently (the latter two items, P < 0.05), suggesting an increase of the information exchange and functional connectivity of different brain regions., Conclusion: Acupuncture of Zusanli (ST 36) can increase the amplitude and synchronization of EEG-delta waves of different leads, and potentiate the functional interconnectivity of brain functional network.

An aerobic denitrifier named F1 was isolated from grass fish pond water by BTB culture medium preliminary screening and denitrification activity analysis. The isolate was identified as Pseudomonas stutzeri through morphological feature, biochemical characteristics and 16S rDNA sequence analysis. Further studies showed that the optimal carbon resources for F1 denitrification were sodium acetate, sodium citrate, glucose and sucrose, with which the nitrate removal rate could reach 100%. When C/N ratio was above 10, the nitrogen removal rate of strain F1 was more than 96% and no nitrite was accumulated. The optimum condition for F1 growth and aerobic denitrification was temperature 30 degrees C and pH 7.0. The F1 could tolerate dissolved oxygen level of 3.4-7.2 mg/L, and its nitrogen removal rate was more than 85% in 24 hours. Denitrification process of F1 mainly occurred in the exponential phase with NaNO3 or NaNO2 as nitrogen resource, and its denitrification rate reached 92.51% and 82.73% , respectively after 32 h of culture. These results suggest that strain F1 can denitrify NO3(-) or NO2(-) directly, and can tolerant a high dissolved oxygen level, and these characteristics make it a good candidate for aquaculture water quality treatment.

Objective: To detect the expression of stem cell transcription factor Oct-4 in squamous cell carcinoma (SCC) and seborrheic keratosis (SK) and its association with cancer stem cells., Methods: Immunohistochemistry was used to detect Oct-4 expression in 35 SCC cases, 21 SK cases and 15 normal control skin tissues., Results: Oct-4 expression was negative in normal skin and showed a significant difference between SCC and SK tissues (P<0.05)., Conclusion: The Oct-4-positive cells in SCC and SK are probably tumor stem cells. Oct-4 expression may provide an important evidence for isolation and identification of human SCC and SK stem cells.

Aim: To detect and characterize of 6 monoclonal antibodies (mAbs) against different epitopes of rat Nogo-A molecule in immunohistochemistry to decide their applications in futrue. Four mAbs against Nogo66 fragment are named Nogo66-1, Nogo66-2, Nogo66-3 and Nogo66-4. The rest of 2 mAbs against N-termial 570-691aa fragment are named NogoN-1 and NogoN-2., Methods: The immunofluorescence staining was used to detect the reactivity and specificity of those 6 mAbs in spinal tissue sections of rat., Results: All 6 mAbs were double-labelled with commercial rabbit anti-Rat Nogo-A polyclonal antibody (PcAb) in spinal cord sections respecitvely. All 6 mAbs were colocalization with MBP respectively. However Nogo66-3 and NogoN-1 could also be double-staining with GFAP respectively., Conclusion: Nogo66-1, Nogo66-2, Nogo66-4 and NogoN-2 could recognize specifically in Nogo-A protein of tissues in immunohistochemical methods.

Objective: To determine the infinite optical thickness of dentine porcelain of IPS E.max A color series., Methods: Cylindrical dentine porcelain specimens of the IPS E.max A color series were prepared with a diameter of 13 mm and thickness of 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 mm. The chromatic value of all the specimens was determined with CM-5 spectrometer against standard black and white background. The chromatic aberration (deltaE) was calculated by regression equation., Results: The infinite optical thickness of dentine porcelain of the IPS E.max A color series ranged from 2.341 to 3.333 mm for a deltaE of 1.0, and from 2.064 to 2.904 mm for a deltaE of 1.5. As the chromaticity or thickness increased, the influence by the background color decreased, and the color of specimens became gradually close to the intrinsic color., Conclusion: The thickness of the background dentine porcelain specimens must exceed its infinite optical thickness to represent the intrinsic color and avoid the influence by the extrinsic color.

Objective: To investigate the effect of three types of veneering porcelain on the bending strength of KAVO Y-TZP/porcelain layered structure., Methods: KAVO zirconia ceramics were used as the substructure. To form Y-TZP/porcelain bilayered structure, a leucite-based veneering porcelain was fired on the zirconia substructures by slip-casting technique with dentin washbake, and two nano-fluorapatite-based veneering porcelains were fired on the zirconia substructures by either slip-casting or pressed-on technique with or without liner coverage. The bending strength was tested according to ISO 6872 standard, and the veneered surfaces of the fracture samples were analyzed by scanning electron microscopy (SEM)., Results: For covering KAVO zirconia core material, the conventional veneering slurry-porcelain combined with liner or wash firing had significant higher bending strength than pressed-on porcelain. SEM showed that the main failure type at the interface was adhesive failure., Conclusion: Thin layer sintering using washbake program or liner on KAVO zirconia surface increases the surface wettability, and this procedure may be indispensable when veneering on the surface of dental zirconia.

Objective: To investigate the effect of two methods of pigmentation on the flexural strength of dental Y-TZP/porcelain layered structure., Methods: KaVo zirconia substructures were pigmented by dipping presintered blocks in the coloring solution VITA LL1 and LL5, and colored TZ-3YS zirconia substructures were fabricated by adding pigments before isostatic pressing. The colors No.1 and No.5 were used for the test. The specimens were made in monolithic or bilayered forms, and the flexural strength was tested. XRD and SEM with EDX were used to analyze the characteristics of the surface structure., Results: In KaVo group, no significant differences were found in the flexural strength between white and LL1 and LL5 colored monoclinic materials, nor in bilayered structures. While in TZ-3YS group, significant differences were noted in the flexural strength between color No.5 white and color No.1 monoclinic materials, but not between the latter two subgroups. The flexural strength was significantly lowered by veneering with porcelain in both zirconia groups, and similar findings were observed with the monoclinic materials. Only the tetragonal phase was detected in both of the zirconia groups., Conclusion: Pigmentation has no apparent effects on the bonding strength between the veneering porcelain and zirconia. Both coloring methods are appropriate when the concentration of the pigments is under deliberate control.

Objective: To study the chemical constituents from the aerial part of Euphorbia chrysocoma., Methods: All compounds were isolated and purified by many methods, including siliga gel and reversed phase RP-18 column chromatographies, preparative thin layer chromatography, Sephadex LH-20, and recrystallization. Their structures were mainly elucidated by ESI-MS and NMR spectra and their physical characters., Results: Six compounds were isolated from the petroleum ether section from 75% ethanol extraction of the material. Their structures were identified as taraxerol (1), epitaraxerol (2), beta-sistosterol (3), beta-sitostenone (4), jolkinolide E (5), and sesamin (6)., Conclusion: Compounds 1, 2, 4, 5, and 6 are isolated from this plant for the first time.

Objective: To determine the chroma value of sintered IL1-IL5 zirconia materials in comparison with the Vita In-Ceram YZ color shade., Methods: Five types of shading dental zirconia ceramics with color gradient were prepared by adding Fe2O3, CeO2, and Bi2O3 to the zirconia powder, and their chroma values were determined using a spectrophotometer and the color difference was calculated., Results: The chroma value ranges were L: 67.76-77.78, a: -2.19-3.80, and b: 12.13-25.01. Slight deltaE was found between IL1 and LL1, IL2 and LL2, and IL3 and LL3. The deltaE between IL4 and LL4 could be compensated by veneering porcelain, whereas deltaL between IL5 and LL5 could not be compensated in this manner., Conclusion: Shading dental zirconia ceramics can be prepared by addition of metal oxides with color similar to the Vita In-Ceram YZ color shades to match that of the veneering porcelain in clinical practice.

Objective: To study the chemical constituents of involatile moiety of Pogostemon cablin., Method: Compounds were isolated and purified by repeated column chromatography, and their structures were elucidated by spectroscopic analysis., Result: Nine compounds have been isolated and identified: epifriedelinol (1), 5-hydroxymethol-2-furfural (2), succinic acid (3), beta-sitosterol (4), daucosterol (5), crenatoside (6), 3'''-O-methylcrenatoside (7), isocrenatoside (8), and apigenin-7-O-beta-D-(6"-p-coumaryl)-glucoside (9)., Conclusion: Compounds 2, 3, 6-8 were isolated from Pogostemon genus for the first time.

Objective: To compare and analyze the mental status of medical staff between Orthopedics Department who treated the victims in the earthquake and other surgical departments who did not treat the victims in the earthquake, and to provide evidence for psychological prevention and intervention in the earthquake aids., Methods: Cross-sectional study was used to choose staff in the Orthopedics Department who treated the victims and other surgical departments who did not treat victims in the earthquake as eligible subject with convenient sampling. The research tool is Symptom Checklist-90. The questionnaire was done by participants with the same psychological instruction. Data were analyzed by SPSS16.0., Results: The scores in somatization, depression,anxiety and opposition, phobic anxiety in the orthopedic staff were significantly higher than those of the other surgical staff (P < 0.05)., Conclusion: There is disorder in mental health of medical staff in Orthopedics Department and mental intervention is needed.