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This study aims to investigate the expression, prognostic value, and function of kinesin superfamily 4A (KIF4A) in cervical cancer.Cervical cancer cell lines (Hela and SiHa) and TCGA data were used for experimental and bioinformatic analyses. Overall survival (OS) and progression free survival (PFS) were compared between patients with high or low KIF4A expression. Copy number variation (CNV) and somatic mutations of patients were visualized and GISTIC 2.0 was used to identify significantly altered sites. The function of KIF4A was also explored based on transcriptome analysis and validated by experimental methods. Chemotherapeutic and immunotherapeutic benefits were inferred using multiple reference databases and algorithms.Patients with high KIF4A expression had better OS and PFS. KIF4A could inhibit proliferation and migration and induce G

To address the problems of thermal damage to a workpiece surface caused by the instantaneous high temperature during grinding and the difficulty in monitoring temperature in real time, the temperature field in the case of composite surface grinding by a cup wheel is studied. In order to predict the grinding temperature, considering material removal and grinding force distribution, a non-uniform heat source model with different function distributions in the circumferential and radial directions in the cylindrical coordinate system is first proposed; then, the analytical model is deduced and the numerical model of the temperature field is established based on the heat source model. The validation experiments for grinding temperature field are carried out using a high-definition infrared thermal imager and an artificial thermocouple. Compared to the temperature field based on the uniform heat source model, the results based on the non-uniform heat source model are in better agreement with the actual temperature field, and the temperature prediction error is reduced from approximately 23% to 6%. Thus, the present study provides a more accurate theoretical basis for preventing burns in cup wheel surface grinding.

High temperature gel permeation chromatography (GPC) equipped with differential refractive index, light scattering and viscometer is used to characterize polyethylene with broad molecular weight distribution (MWD). Methods are discussed through the measurement of broad MWD polyethylene PE52K and 4731B, including Mark-Houwink calibration, universal calibration, triple-detectors and light scattering dual-detectors calibrations. As the broadness of MWD increases, the two fitting curve calibrations with first order equations are chosen, despite a slight inaccuracy within molecular weight range of standards. More reliable polymer dispersity indexes (PDI) are obtained by triple-detectors and light scattering dual-detectors calibrations. From the Mark-Houwink plot of 4731B, branching information can only be obtained from triple-detectors calibration, indicating the validity of triple-detectors calibration on the characterization of branched polyethylene with broad MWD. The triple detectors calibration upon 4731B provides a weight average molecular weight of 313 kg/mol, a PDI of 47 and a branching of 0.30 per chain.

Background: Hand injuries are very common in sports, such as skiing and ball sports. One of the major reasons causing hand and finger deformity is due to ligament and tendon injury. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) can demonstrate the complex anatomy of the fingers and thumb, especially the tendons and ligaments, and provide the accurate diagnosis of clinically important fingers and thumbs deformity due to ligamentous and tendinous injuries during sport activities. Methods: Sixteen fresh un-embalmed cadaveric hands were harvested from eight cadavers. A total of 20 healthy volunteers' hands and 44 patients with fingers or thumb deformity due to sports-related injuries were included in this study. All subjects had MR examination with T1-weighted images and proton density-weighted imaging with fat suppression (PD FS) in axial, coronal, and sagittal plane, respectively. Subsequently, all 16 cadaveric hands were sliced into 2-mm thick slab with a band saw (six in coronal plane, six in sagittal plane, and four in axial plane). The correlation of anatomic sections and the MRI characteristics of tendons of fingers and the ulnar collateral ligament (UCL) at the metacarpal phalangeal joint (MCPJ) of thumb between 20 healthy volunteers and 44 patients (confirmed by surgery) were analyzed. Results: The normal ligaments and tendons in 16 cadaveric hands and 20 volunteers' hands showed uniform low-signal intensity on all the sequences of the MRI. Among 44 patients with tendinous and ligamentous injuries in the fingers or thumb, 12 cases with UCL injury at MCPJ of the thumb (Stener lesion = 8 and non-Stener lesion = 4), 6 cases with the central slip injury, 12 cases with terminal tendon injury, and 14 cases with flexor digitorum profundus injury. The ligaments and tendons disruption manifested as increased signal intensity and poor definition, discontinuity, and heterogeneous signal intensity of the involved ligaments and tendons. Conclusions: Sports injury-related fingers and thumb deformity are relatively common. MRI is an accurate method for evaluation of the anatomy and pathologic conditions of the fingers and thumb. It is a useful tool for accurate diagnosis of the sports-related ligaments and tendons injuries in hand.

To investigate if using high-resolution 3-T MRI can identify additional injuries of the triangular fibrocartilage complex (TFCC) beyond the Palmer classification. Eighty-six patients with surgically proven TFCC injury were included in this study. All patients underwent high-resolution 3-T MRI of the injured wrist. The MR imaging features of TFCC were analyzed according to the Palmer classification. According to the Palmer classification, 69 patients could be classified as having Palmer injuries (52 had traumatic tears and 17 had degenerative tears). There were 17 patients whose injuries could not be classified according to the Palmer classification: 13 had volar or dorsal capsular TFC detachment and 4 had a horizontal tear of the articular disk. Using high-resolution 3-T MRI, we have not only found all the TFCC injuries described in the Palmer classification, additional injury types were found in this study, including horizontal tear of the TFC and capsular TFC detachment. We propose the modified Palmer classification and add the injury types that were not included in the original Palmer classification.

In the present study, we explored the effectiveness and complications of omnidirectional internal fixation using a double approach for treating Rüedi-Allgöwer type III pilon fractures. A retrospective analysis was performed of 19 cases of Rüedi-Allgöwer type III unilateral closed pilon fracture. With preoperative preparation and correct surgical timing, the reduction was performed using anteromedial and posterolateral approaches, and the fracture fragments were fixed by omnidirectional internal fixation. Imaging evaluation was performed using the Burwell-Charnley scoring system. The Johner-Wruhs scoring system was used to assess the functional status of the patients. A comprehensive evaluation of efficacy was performed using a 5-point Likert score. The complications were also recorded and analyzed. All patients were followed up for an average of 16.2 months. The operative incisions of 15 cases healed by primary intent and with delayed healing in 4. All patients had achieved bony union at an average of 16 weeks postoperatively. No deep infection, broken nail or withdrawn nail, exposed plate, or skin flap necrosis occurred. The Burwell-Charnley imaging evaluation showed that 14 patients had anatomic reduction of the articular surface and 5 had acceptable reduction. Using the Johner-Wruhs scoring system, the results were excellent for 8, good for 7, fair for 2, and poor for 2 patients; the combined rate of excellent and good results was 78.9%. The Likert score of efficacy self-reported by the patients was 3 to 4 points for 12 patients, 2 points for 4 patients, and 0 to 1 point for 3 patients. The Likert score of therapeutic efficacy reported by the physicians was 3 to 4 points for 10 patients, 2 points for 5 patients, and 0 to 1 point for 4 patients. Omnidirectional internal fixation using double approaches was an effective method to treat Rüedi-Allgöwer type III pilon fractures with satisfactory reduction and rigid fixation, good joint function recovery, and few complications.

A non-linear torsional vibration model of harmonic gear drive is proposed in the current study. The model includes clearance, nonlinearity torsional stiffness and nonlinearity damping. The clearance model is developed by introducing the piecewise-linear displacement functions. The function of nonlinearity torsional stiffness is obtained by torsional stiffness experimental. The model of nonlinearity damping is used to describe the process of transmission. The non-linear differential equations are solved using Runge-Kutta method. The numerical simulation results show that the influence of nonlinear factors on dynamic behavior, which has chaotic characteristics, is remarkable.

With the rapid development of coal mine resources, heat harm in deep mine is one of the key problems to be solved in our country. In this article, through analyzing the different heat sources of the mine,we get the calculation model of airflow temperature which is related to the different feature points of shaft , horizontal and slant roadways and extraction working areas.We also take the actual geological conditions into consideration and build simulation system in coal mine to imitate and budget the airflow temperature and air amount in roadway which is at different ventilation system conditions. And it can provide theoretical and technical basis for the optimization scheme research of mine ventilation system , the ways to choose the mine refrigeration system and installation position of air cooler.

This work presents an investigation on wear prediction of multibody system including dry revolute clearance joint using a computational methodology. A procedure to analyze multibody system in which wear is present at revolute joints is presented. The study involves integrating a dynamics model of the mutibody system with clearance joint into a wear prediction procedure. The contact model in clearance joint is established using a hybrid nonlinear contact force model and the friction effect is considered by using a modified Coulomb friction model. The wear modeling of revolute clearance joint in multibody systems is presented based on the Archard's wear model. Finally, an academic four-bar multibody mechanical system with revolute clearance joint is used as numerical example application to perform the investigation.

A detailed model of nonlinear self-consistent simulation for a coaxial-waveguide cyclotron autoresonance maser amplifier is presented to analyse the nonlinear characteristics of the device. Mode spectrums in cylindrical-waveguide and coaxial-waveguide are analysed. The effects of the electron-beam velocity spread and the misalignment between the electron-beam axis and the waveguide axis on the characteristics of the device are investigated and found to be detrimental to the power and efficiency. Specific simulations show that the output power and the efficiency drop from 493.4 kW and 10.97% to 382.33 kW and 8.5% when the axial velocity spread is 1% and decrease to 3.33% efficiency at 0.1 cm misalignment. However, the use of a tapering guide magnetic field with a slope e = −0.001 cm−1 and the starting position z = 25 cm may enhance the power and efficiency to 1.84 MW and 40.82%, respectively.

IntroductionUrethral stricture, a frequent source of lower urinary tract disorders in men, is still a difficult problem for urologists. Based the anti-restenosis effect of paclitaxel on coronary artery, the role of docetaxel, a semi-synthetic analogue of paclitaxel, in limiting urethral stricture formation was studied.MethodsForty adult New Zealand male rabbits were involved in this study, which were randomly assigned into 3 groups, namely a high dose docetaxel (DH, 0.1 mg/d), a low dose docetaxel (DL, 0.01 mg/d) and a control (C) group, with 16, 16, 8 rabbits in each group, respectively. All animals underwent a 10 mm-long circumferential electrocoagulation of the bulbar urethra with a 13Fr pediatric resectoscope. Drugs were given by urethral irrigation daily and continuous for 28 days. Stricture formation was assessed by retrograde urethrography and videourethroscopy. Urethra pathology was evaluated by hematoxylin and eosin staining and Sirius red staining.ResultsAt the end of this study, 15, 14 and 7 rabbits remained for evaluation in DH, DL and C group, respectively. Urethral diameters in DH, DL and C group were (7.17±1.63) mm, (6.55±0.62) mm, (3.23±1.36) mm, with a normal urethral diameter of (9.08±1.29) mm. Lumen reduction in DH, DL and C group were (36.93±11.58)%, (48.03±7.89)% and (84.66±14.95)%, respectively. Statistically difference could be found between every two groups (pConclusionsDocetaxel could limit urethral stricture formation, which may be due to inhibition of fibrous tissue and collagen expression. Docetaxel may become a new choice in the prevention of urethral stricture formation.

A nonlinear self-consistent simulation code is employed to investigate the behavior of the outer-slotted-coaxial waveguide gyrotron traveling-wave amplifier (gyro-TWA). The influences of the velocity pitch, frequency, and input power of the electron beam on efficiency, output power, and saturated gain are simulated and discussed in detail. It is predicted that this design with 95 GHz, TE/sub 3,1/ will yield a peak output power of 264.3 KW, a peak efficiency of 33.7%, and saturated gain of 44.2 dB.

A self-consistent nonlinear theory for the outer-slotted-coaxial-waveguide cyclotron autoresonance maser (CARM) amplifier is presented, which includes the characteristic equation of the wave, coupling equation of the wave with the relativistic electron beam and the simulation model. The influences of the magnetic field, the slot depth and width are investigated. The interesting characteristic of the device is that the mode competition can be efficiently suppressed by slotting the outer wall of the coaxial waveguide. A typical example is given by the theoretical design of a 137 GHz outer-slotted-coaxial-waveguide CARM amplifier by utilizing an electron beam with a voltage of 90 kV, current of 50 A, velocity pitch angle of 0.85 and a magnetic field of 43.0 kG. The nonlinear simulation predicts a power of 467.9 kW, an electronic efficiency of 10.4% and a saturated gain of 46.7 dB, if the electron beam has no velocity spread. However, the axial velocity spread deteriorates the device; for example, if the axial velocity spread is 2%, the peak power decreases to 332.4 kW with an efficiency of 7.4% and a saturated gain of 45.22 dB. Simulation shows that the efficiency of the outer-slotted-coaxial-waveguide CARM amplifier may be increased from 10.4% to 29.6% by tapering the magnetic field.

Nonlinear simulations demonstrate the possibility for a coaxial-waveguide cyclotron autoresonance maser (CARM) amplifier to operate at a frequency of 140 GHz emitting hundreds of watts with an ultrahigh gain of 68 dB. Careful design of the operating magnetic field is of importance to the power of the device, although the other initial parameters such as electron-beam radius and voltage also affect the power. Like a cylindrical-waveguide CARM, a coaxial-waveguide CARM amplifier is sensitive to the velocity spread of the electron beam.

A coaxial-waveguide gyrotron-traveling wave amplifier is proposed, which may be suitable for the operation in the spectrum of the short millimeter and submillimeter waves with good mode selectivity, high power, and ultrahigh gain. An example is presented in terms of the linear gyrokinetics and nonlinear simulations. Theoretical results show that tens of kilowatts with ultrahigh gain up to 67 dB might be achieved for the operation of the coaxial-waveguide mode TE/sub 28,16/ in the fundamental cyclotron harmonic at the frequency of 140 GHz. The power enhancement by a tapered magnetic field is discussed.

A nonlinear approach is presented to simulate the coaxial-waveguide cyclotron autoresonance maser (CARM) amplifier. Simulation shows an interesting result that the efficiency of a coaxial-waveguide CARM amplifier may be increased from 7.5% to 33.9% by tapering the magnetic field.

A coaxial-cavity cyclotron resonance maser (CRM) oscillator with tapered guide magnetic field is proposed. It is shown that the transmission quality can be improved by tapering the guide magnetic field. Simulation indicates that the efficiency of a millimeter-wave gyrotron oscillator may be reached up to 38.7% by optimizing the tapered magnetic field.

The free-electron laser (FEL) based on the self-amplified spontaneous emission (SASE) is an effective candidate of the coherent optical sources at wavelengths in ultraviolet and x-rays. It requires a relativistic electron beam with extremely high quality and extremely stable transmission. In this paper we analyze the dynamic behavior of the relativistic electron in that device by calculating the entropy-like quantity. Results show that if there is no adiabatic field of the wiggler, the electron beam may have great fluctuation in velocity space and diverge in configuration space.

To explore the value of Magnetic resonance imaging (MRI) in the early rheumatoid arthritis (RA).56 patients (24 men and 32 women) fulfilling the 2010 ACR/EULAR for RA, 34 with early RA, and 22 with established RA, (disease duration12 months, and12 months, respectively) were enrolled in the study. MRI of the dominant hand and wrist was performed by using short time inversion recovery (STIR), plain and contrast-enhanced T1-weighted sequences. Evaluation of bone marrow edema, bone erosions and synovitis was performed with the OMERACT RA MRI scoring system.Edema, erosions, and synovitis were present in early RA and established RA, and the prevalence was 88.2% (30/34), 91.1% (31/34), 100% (34/34) and 90.9% (20/22) , 95.4% (21/22), 100% (22/22) , respectively. But no significant difference was found in two group (P0.05). Significant differences in edema and erosions were found between earlier RA and established RA (P0.05). No significant difference was found in synovitis (P0.05).Bone marrow edema, bone erosions and synovitis are important sign of early RA. But bone edema and erosions in MRI may play an important role in the diagnosis of early RA.

A coaxial Bragg reflector is suggested for the application in the cyclotron autoresonance masers (CARMs), where both the outer wall and inner rod are corrugated with weak axisymmetric-sinusoidal-ripple, and a concept design is presented. It is found that, compared to the cylindrical Bragg reflector, the coaxial Bragg reflector has larger dimensional size, narrower bandwidth, and larger eigenvalue intervals. These peculiarities are favorable to the mode selectivity, the ability of dissipating the ohmic heat on the wall, the oscillating startup of the operating mode, and machining manufacture, and therefore, this new kind of Bragg reflector can be developed into a coaxial resonator for the high-power CARMs

Rapamycin has been reported to inhibit hepatic fibrosis, lung fibrosis, renal fibrosis, and subglottic stenosis. Fibrosis is also involved in urethral stricture. Therefore, we investigated the effect of rapamycin on the inhibition of urethral stricture formation in a rabbit model. First, models of urethral stricture were successfully established by electrocoagulation of the bulbar urethra in adult New Zealand male rabbits. Forty-six model rabbits were randomly assigned to four groups: high-dose rapamycin (R(H), 1.0 mg/day), low-dose rapamycin (R(L), 0.1 mg/day), dimethyl sulfoxide (DMSO) alone (DMSO, solvent control), and normal saline (NS). Urethral stricture was assessed by a retrograde urethrogram and video-urethroscopy. Urethra pathology was evaluated by hematoxylin and eosin and Sirius red staining. After 28 days of treatment, lumen reduction in the R(H), R(L), DMSO, and NS groups was 36.0, 56.5, 69.1, and 82.9, respectively. Comparison of the rapamycin groups (R(H) and R(L)) and control groups (DMSO and NS) indicated significantly less restriction in the rapamycin groups. Histopathological analysis confirmed the presence of fibroblasts and an increase in collagen at the stricture site in the two control groups but not in the R(H) or R(L) groups. These results indicate that rapamycin inhibits experimentally induced urethral stricture formation in rabbits. This effect may be due to its inhibition of fibroblast proliferation and collagen expression.

Operation of a gyro-TWT amplifier with helical interaction waveguide is investigated by means of nonlinear self-consistent code. Simulation results are in good agreement with reported experimental observation. Reduced sensitivity to the electronspsila velocity spread and broad bandwidth of this type of gyro-device are demonstrated.

A 35-GHz, TE5,1-mode large-orbit coaxial-waveguide CARM amplifier is specifically analyzed. Results show that the operating magnetic field and the electron-beam energy and average radius substantially affect the power, and especially, a small beam current may be unsuitable to a large-orbit CARM amplifier operation.

Nonlinear simulation shows that the misalignment between the electron-beam axis and the waveguide axis substantially decreases the output power of a coaxial-waveguide cyclotron autoresonance maser (CARM) amplifier. This investigation is of importance, because, in practice, there often exists the misalignment between the electron-beam axis and the waveguide (or cavity) axis, and it has been shown by experimental and theoretical studies that this kind of misalignment has substantial influence on the performance of both the cylindrical-cavity and coaxial-cavity gyrotron oscillators.

A calculation approach for evaluating RF-field distribution in an eccentrically coaxial cavity is proposed, where the theoretical model is based on the solution of scalar Helmholtz equation. Numerical analysis is carried out to compare with the software HFSS that is based on the finite element method. It is found that, although the results obtained by these two methods are in close agreement for lower-order modes, both the calculation time and memories used by the present approach are much less than that needed by the software HFSS, and especially, the present approach is still valid for the higher-order mode such as TE/sub 28,16,1/and higher frequency up to hundreds giga hertz which the software HFSS can hardly process.

Structure of cyclotron autoresonance maser (CARM) amplifier with outer-inner-slotted waveguide is proposed. The attractive features are large waveguide radii and low magnetic field. A linear theory for outer-inner-slotted-waveguide CARM amplifier is developed. It is shown using nonlinear simulation code that the proposed device may be well suited for operate at both high power and high gain in millimeter wave and far infrared regions. Example is presented for an outer-inner-slotted waveguide optimized CARM amplifier designed to operated in the TE/sub 28,16/ mode at 138 GHz, yielding a power of 540.33 kW on using a 90 kV and 50 A electron beam controlled by a 43.24 kG magnetic field. The influence of waveguide structures including slot width ratio and the ratio of inner radii to outer radii of outer slot on the output power are investigated. The mode competition is discussed in conclusions.

A numerical approach is presented to analyze the eigenfrequency of a coaxial cavity with large eccentricity. An example is given to a lower mode TE/sub 111/ to compare with the software HFSS, where the eccentricity is up to 70%. Generally, this approach has the following peculiarities: the CPU time needed is much less than that needed by the software HFSS and especially, the calculation can be easily extended to higher-order mode such as TE/sub 28,16,11/as well as to high-frequency domain of hundreds giga hertz, which the software HFSS hardly reaches.