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With the depth increasing and the improvement of mining mechanization of the coal mine, heat hazard is becoming more and more serious, the ice cooling system is gradually promoted and applied in China for recent years, but the cooling capacity and energy efficiency ratio (EER) test and analysis for such system is seldom reported. The cooling capacity and EER of the refrigerating equipment of an ice cooling system of a coal mine are tested and analyzed in Shandong Province in this paper. The test result indicates that the refrigerating capacity and EER are lower and both the pre-cooling units and the ice making system have a large variable range. It points out that it should not evaluate the ice cooling system by the test data only in this mine but expect more test data and analysis of the ice cooling system in other coal mines to get a more scientific conclusion. And the test, analysis and comparison for different kinds of cooling system are also expected to explore suitable cooling system while a full consideration of the geological conditions and other factors of the mine are taken into consideration.

Circulating Tumor Cells (CTCs) are cancer cells that split away from the primary tumor and appear in the circulatory system as singular units or clusters, which was first reported by Dr. Thomas Ashworth in 1869. CTCs migrate and implantation occurs at a new site, in a process commonly known as tumor metastasis. In the case of breast cancer, the tumor cells often migrate into locations such as the lungs, brain, and bones, even during the early stages, and this is a notable characteristic of breast cancer. Survival rates have increased significantly over the past few decades because of progress made in radiology and tissue biopsy, making early detection and diagnosis of breast cancer possible. However, liquid biopsy, particularly that involving the collection of CTCs, is a non-invasive method to detect tumor cells in the circulatory system, which can be easily isolated from human plasma, serum, and other body fluids. Compared to traditional tissue biopsies, fluid sample collection has the advantages of being readily available and more acceptable to the patient. It can also detect tumor cells in blood earlier and in smaller numbers, possibly allowing for diagnosis prior to any tumor detection using imaging methods. Because of the scarcity of CTCs circulating in blood vessels (only a few CTCs among billions of erythrocytes and leukocytes), thorough but accurate detection methods are particularly important for further clinical applications.

Transcription intermediary factor 1γ (Tif1γ), a ubiquitous nuclear protein, is a regulator of transforming growth factor‑β (TGF‑β)/Smad signaling. Tif1γ can function as an oncogene and as a tumor suppressor. In the present study, Tif1γ levels were measured in the plasma of patients with breast cancer in order to investigate the association of Tif1γ with overall survival (OS). The results indicated that Tif1γ is an independent prognostic and predictive factor in breast cancer, and thus, a promising target protein for use in diagnostics and patient follow‑up. Plasma levels of Tif1γ were measured in samples obtained from 110 patients with operable breast cancer and in 110 healthy volunteers at the Breast Cancer Department of Yangpu Hospital between 2008 and 2016. The association between Tif1γ levels and clinicopathologic parameters, and the OS in a follow‑up period of 98 months was evaluated. The prognostic significance was assessed using the Kaplan‑Meier method. The levels of Tif1γ were significantly lower in patients with breast cancer compared with healthy controls. The average concentration of 18.40 ng/ml was used to discriminate between Tif1γ‑positive (52) and Tif1γ‑negative patients (58). Tif1γ‑positive patients had a significantly improved OS compared with Tif1γ‑negative patients. In the multivariate analysis, Tif1γ was an independent predictor of a favorable OS in a prospective follow‑up setting; thus, Tif1γ plasma levels are an independent prognostic factor for patients with breast cancer. These findings support the potential of using measurements of Tif1γ plasma levels to guide breast cancer therapy and monitoring. Further studies are required to validate Tif1γ as an easily detectable, non‑invasive prognostic biomarker for breast cancer.

We proposed a high sensitivity and a high resolution surface plasmon resonance sensor composed of graphene–WS2 hybrid nanostructure and Au–Ag bimetallic-layers film. The bimetallic-layer configuration uses the high sensitivity of gold and the narrow full width at half maximum (FWHM) of silver to improve the sensor's sensitivity and resolution respectively. Graphene and WS2 serve as an effective light absorption medium. Once they cover the bimetallic-layer, the sensitivity can be further improved significantly. Graphene–WS2–Au–Ag model shows a higher sensitivity and higher resolution than that of the conventional sensing scheme where pure Au thin film is used. In our paper, we mainly use Fresnel equations and the transfer matrix method (TMM) to study the reflectivity and sensitivity as well as the full width at half maximum (FWHM) of the SPR sensor.

Anthracyclines are highly effective chemotherapeutic agents, used for a wide variety of malignancies. Cardiotoxicity is a well-recognized side effect of anthracycline therapy that limits the total amount of drug administered and can cause heart failure in some patients. Most experimental data support oxidative stress as the etiology of anthracycline-induced cardiotoxicity. The objective of this paper was to provide a review of the clinical classification, risk factors, monitoring and prevention of anthracycline-induced cardiotoxicity in patients with breast cancer.

Nanogap-rich silver nanoislands with fascinating optical properties are desirable substrates for surface-enhanced Raman scattering (SERS). Here, we propose a simple and high-throughput approach through the laser molecular beam epitaxy (LMBE) technique for preparing silver nanoislands containing large numbers of intra-nanogaps on a silicon wafer (6×6 cm2). By optimizing the deposition time, the enlarged silver nanoislands with ∼5 nm interstitial gaps of abundance and homogeneity were formed. Remarkably, the optimized SERS substrate with high-density hotspots demonstrated a high analytical enhancement factor (AEF) as large as 1.17×105, excellent reproducibility with relative standard deviation (RSD) of 7.76% over the entire substrate, and good stability after storage for 21 days. The electromagnetic field distribution of the optimized SERS substrate was simulated using the software COMSOL Multiphysics based on the actual SEM image of the fabricated sample, and the calculated enhancement factor (EF) is as high as 109. Furthermore, it can enable sensitive and quantitative detection of malachite green at concentrations as low as 10−8 M. This simple fabrication of silver nanoislands with homogeneous ∼5 nm interstitial gaps provides a practical solution for wafer-scale, sensitive, and reproducible SERS substrates.

In this paper, we designed a 2D distance and rotation angle plasmon ruler based on Fano resonance of a trimer nanostructure, which consists of a concentric square nanoring–disk and an outside nanorod (CSRDR). The Fano dip energy and depth are fairly sensitive to the nanometer-scale displacements and rotations, when the nanodisk moves in all direction and rotates around its center. When the symmetry of the nanoring is broken, we can identify the moving and rotating direction of the nanodisk more accurately. We use the CSRDR nanostructure which supports a narrow line-width as a 2D plasmon ruler, which can enhance the sensitivity of a plasmon ruler significantly.

The development of paper-based SERS substrates that can allow multi-component detection in real-word scenarios is of great value for applications in molecule detection under complex conditions. Here, a multifunctional SERS-based paper sensing substrate has been developed through the uniform patterning of high-density arrays of GO-isolated Ag nanoparticles on the hydrophilic porous cellulose paper strip (GO@AgNP@paper). Wet-chemical synthesis was used to provide the cover of SERS hot spots on any part of the paper, not just limited surface deposition. In virtue of the inherent ability of paper to deliver analytes by the capillary force, the detection ability of the GO@AgNP@paper substrate was greatly promoted, allowing as low as 10-19M R6G detection from microliter-volume (50 μL) samples. For the components with different polarity, the paper substrate can be used as an all-in-one machine to achieve the integration of separation and high-sensitive detection for ultralow mixture components, which improves the practical application value of SERS-based paper devices.

We investigate a new class of nondiffracting optical beams carrying fractional orbital angular momentum (FOAM Bessel beams), which can be constructed by modifying the phase step of the spiral phase plate in a setup originally for the generation of traditional Bessel beams. The FOAM Bessel beams have entirely stable vortex structures, and form an infinite number of orthogonal and complete subsets for monochromatic scalar light in free space. With the advantages of structural stability and orthogonality-completeness, the FOAM Bessel beams are expected to be useful for study and application in various fields of modern optics.

In the process of cutting, cutting tool wear has an important influence on the surface quality of the work piece, therefore, it is of great significance for the research of tool wear detection. In this paper, this work focuses on researching relationship between cutting force and tool flank wear. In different experiment conditions, the consistency of the results of simulation and experiment results was obtained through the comparative analysis between the two. It is a complex problem that cutting tool wear and measuring process and not easy to get the accurate ideal results by experiment， the simulation experiment has the characteristics of simple and easy to operate and the result is diminutively influenced by complex factors, therefore, it is the primary method to carry out this work by simulation experiment .In this paper, it is mainly investigated into the simulation analysis of the tool flank wear. The specific content of the simulation experiment is explaining the causation for the tool flank wear through the analysis of the temperature field at the tip and obtaining the data of cutting force in different tool flank wear(10,100,200,300um). The empirical cutting force model was established through multiple regression analysis and the tool flank wear prediction model was reversed and gained by analysis of the results of simulation experiments.

Passively Q-switched mode-locked dual-wavelength Nd:GYSGG laser using graphene oxide saturable absorber is demonstrated. The output spectrum peaked at 1057.28 nm and 1060.23 nm with wavelength spacing of 3 nm has been measured. At the pump power of 5 W, the maximum average output power of 0.189 W was obtained with the optical conversion efficiency of 3.79%. The mode-locked pulse inside the Q-switched envelope has a repetition rate of 100 MHz and its pulse width is estimated to be about 441 ps. In addition, a simple way to fabricate few layers graphene oxide saturable absorbers has been reported.

A dual-wavelength self-Q-switched operation of Nd:GYSGG laser with different output couplers is proposed and demonstrated. In self-Q-switched operation, two laser lines between 1056.86 nm and 1060.23 nm were found. Under the pump power of 4 W, the shortest pulse width of 2.02 μs was obtained with a maximum average output power of 565 mW and the optical conversion efficiency of 14.13%. The pulse repetition rate and single pulse energy were 50.2 kHz and 11.25 μJ, respectively. The system is very stable and suitable for generation of multi-wavelength pulses.

A homogeneous titanium oxide device is fabricated by Molecular Beam Epitaxy and the excellent memristive behavior could be observed. The resistance ratio between high resistance state and low resistance state increases as the thickness of titanium oxide or the oxygen content reduces. The forming voltage is lower than the previous report. Based on the experimental results, we suggest a double-interface conductive filament model and calculate the current–voltage curve of the device in agreement with experimental measurements. The result indicates that the forming voltage of the device will rise with increasing of the chemical potential differences across the two interfaces. In other words, the switching voltage could be adjusted by selecting a proper electrode and oxide materials.

We demonstrate the use of molybdenum disulfide (MoS2)-based saturable absorber to develop a passively Q-switched Nd:YVO4 laser. The few-layer MoS2 saturable absorber was prepared by mixing MoS2 with alcohol and then evaporating the mixture on a substrate. Using an MoS2 saturable absorber, stable Q-switching operation was achieved with a laser pulse width of 327 ns and a repetition rate of 5 kHz under a pump power of 2.23 W. Due to the simple manufacturing process and high saturated absorption characteristics, MoS2 seems to be a suitable material as a saturable absorber for solid-state lasers.

The structure of 1 × 2 type photonic crystal power splitter with ring resonators is designed in a two-dimension square-lattice dielectric-rod photonic crystal structure, and it consists of one input and two outputs. Its transmission performance is investigated by using the finite-difference time-domain (FDTD) method. The results show that the structure has high transmission efficiency in the third communication window (wavelength 1550 nm), can split pass band electromagnetic waves equally. It is compact with low loss and design flexibility in propagation direction of electromagnetic waves.

Metal film is an essential part of the electrically pumped organic semiconductor lasers. But the large loss is the most important factor restricting the electrical pumping. In this paper, we investigate optically pumped amplified spontaneous emission (ASE) in the presence of metal films. The ASE threshold of device with metallic film is reduced by 2.5 times in comparison with that of the metal-free devices. The SiO2 space layer with optimizing thickness between gain media and metal film can effectively prevent absorption loss but also provides a proper waveguide effect. Furthermore, the metal film can prevent the light leaking to the substrate and reflect the lights back into the media, which increases the intensity of pumping and emission again.

We have fabricated blue organic light-emitting devices (OLEDs) with higher color purity and stability by optimizing the structure of the Glass/ITO/NPB(50 nm)/ BCzVBi (30 nm)/ TPBi (x nm)/Alq3(20 nm)/LiF/Al. The results show that the introducing of hole blocking layer(HBL) TPBi greatly can improve not only the color purity but the color stability, which owe to its higher the Highest Occupied Molecular Orbital (HOMO) energy levels of 6.2 eV. We expect our work will be useful to optimizing the blue OLEDs structure to enhancing the color property.

The contribution of the Green's function to the scattered magnetic field is not well expressed in the traditionally used magnetic field integral equation (MFIE) when the source and field points lie on the same plane. This decreases the accuracy of MFIE for objects with flat surfaces. To solve this problem, the normal magnetic field integral equation resulting from the use of the normal boundary condition is considered. It is then combined with the traditionally used MFIE into a new MFIE formulation, named the combined magnetic field integral equation (CMFIE). Through the use of an appropriate combination parameter, the omitted contribution of the Green's function to the scattered magnetic fields in the traditionally used MFIE can be recovered in this new CMFIE. Numerical results validate the analysis and show that the proposed MFIE formulation is much more accurate than the traditional one for small objects with flat surfaces.

Passively Q-switched mode-locking performance of Nd:GdTaO4 crystal using molybdenum disulfide (MoS2) as a saturable absorber at 1066 nm was demonstrated for the first time. The MoS2 saturable absorber was prepared simply by transferring the MoS2 suspension onto a quartz substrate. By inserting the MoS2 saturable absorber into the Nd:GdTaO4 laser, stable Q-switched modelocked operation can be achieved. At the pump power of 4 W, the maximum average output power of 0.156 W was obtained with the optical conversion efficiency of 3.9%.

The performance of a diode end-pumped passively Q-switched dual-wavelength Nd:GYSGG laser operating at 1057.28 and 1060.65 nm with graphene oxide as the saturable absorber was demonstrated. The maximum dual-wavelength average output power of 521 mW was achieved under the absorbed pump power of 5.4 W, corresponding to the optical-to-optical conversion and slope efficiency of 9.8% and 21%, respectively. The minimum pulse width was 115 ns with a pulse repetition rate of 338 kHz.

A free electron laser (FEL) amplifier with an elliptical waveguide and a planar wiggler is proposed. A set of coupled operating equations for this FEL operating in the Raman regime is derived using three-dimensional nonlinear theory. The numerical simulation code is developed, and the characteristics of this FEL amplifier are analysed numerically. Our numerical simulations are conducted to model a 34.6 GHz amplifier with an electron beam with an energy of 3.1 MeV. The results indicate that the elliptical waveguide is more suitable for a FEL with a planar wiggler system than a rectangular waveguide.

A novel Smith–Purcell (SP) free-electron laser (FEL) with axial-symmetrical structure is proposed. The distribution of the high frequency field in the resonator is analyzed and the operating frequency and output power are also studied by the use of particle-in-cell (PIC) simulation method. Results indicate that coherent radiation with output peak power up to 58 MW at millimeter wavelengths can be generated by using relativistic electron beams of moderate energy.

The compact free electron maser (FEM), with the advantages of small size and low cost, is important for realistic applications in medicine and industry. In order to utilize the planar wiggler to the best advantage and simultaneously to reduce the necessary electron beam voltage and the size of FEM device, we propose to utilize an elliptical waveguide as the high frequency structure of planar wiggler FEM. A set of universal operating equations suitable for elliptical waveguide and rectangular waveguide FEMs is derived by using the nonlinear theory. The characteristics of the FEMs are numerically analyzed, comparatively.

Dispersion equation of planar-wiggler free-electron laser with background plasma is derived using linear fluid theory. The characteristic of this plasma FEL is analyzed in detail. It is shown that reasonable background plasma density tends to improve FEL growth rate. We also find there exits a critical plasma density for FEL operating. When the background plasma density is higher than critical density, the FEL can no longer be excited.

A set of nonlinear three-dimension equations for the FEM amplifier with elliptical waveguide and planar wiggler is derived. Based on these equations, a universal numerical simulation program is developed independently. The characterisitics of this FEM including the evolution of power, saturation efficiency and bandwidth are investigated. Electron momentum spread and wiggler taper are also considered.

The physical phenomenon, surface-enhanced Raman scattering (SERS), is mainly based on the local electromagnetic fields enhancement located at the nano-gaps between metal nanostructures attributed to localized surface plasmon resonance. Therefore, nano-gaps are very important for obtaining high-density hot spots and optimal and uniform SERS signals. However, it remains a challenge to form the three-dimensional ultra-narrow nano-gaps. Here, a gyrus-inspired Gyrus-SERS substrate was fabricated with the nanostructure of Ag gyrus/graphene/Au film using an extremely simple method. The lateral and vertical hot spots respectively were obtained from the dense nano-gaps (~3 nm) between gyrus and the coupling of Ag gyrus and Au film in bilayer graphene nano-gaps (0.68 nm), which were demonstrated in experiment and theory. The proposed Gyrus-SERS platform performs an excellent SERS activity (EF~5 × 109), high sensitivity (the minimum detected concentration of R6G and CV respectively is 10−13 and 10−12 M), and outstanding reproducibility (RSD~7.11%). For practical application, the in situ detection of Malachite green (MG) residue on prawn skin was executed using the prepared flexible Gyrus-SERS substrate, which shows the wide potential in food safety field.

We experimentally demonstrated a laser diode-pumped Q-switched Nd:GdTaO4 crystal laser at 1066 nm using a multilayer graphene oxide as the saturable absorber (GOSA). The GOSA is fabricated by transferring the liquid-phase-exfoliated GO nanosheets onto a K9 glass substrate. When the GOSA was inserted into the plano–plano laser cavity, a stable Q-switched laser operation is achieved with a maximum average output power of 0.382 W and repetition rate of 362 kHz. The shortest pulse duration is 194 ns and the single pulse energy is about 1.05 μJ.

OBJECTIVE: Our purpose was to investigate the spatiotemporal properties of the fetal magnetocardiogram. STUDY DESIGN: Fetal magnetocardiogram maps were measured for the first time in 20 subjects from 22 to 39 weeks' gestation. Waveform and topographic maps were used to display the data. RESULTS: The maps showed spatiotemporal properties consistent with simple volume conductor theory: topography was closely related to the presentation of the fetus, Q-wave sources were dipolar and localized, the magnetic heart vector rotated extensively during the QRS complex, and close correspondence was observed between fetal and neonatal maps. Ventricular depolarization and events in the cardiac cycle could be visualized in considerable detail by means of a time series of topographic maps. CONCLUSION: Fetal magnetocardiogram shows excellent spatiotemporal properties and is well suited for in utero studies of fetal heart activity. (AM J OBSTET GYNECOL 1994;170:770-6.)

Fetal heart rate variability was derived from fetal magnetocardiogram recordings in ten subjects at gestation ages 32–38 weeks. Maternal interference was negligible and R-wave detection was highly reliable. Oscillations suggestive of respiratory sinus arrhythmia (RSA) were prominent in many of the heart rate tracings. Spectral analysis was used to quantify heart rate variability and to examine the influence of the RSA-like oscillations on heart rate variability. The oscillations were associated with increased power in the frequency range 0.4–1.0 Hz (P ≤ 0.05). Magnetic recording appears to offer significant advantages for investigation of beat-to-beat fetal heart rate throughout the latter stages of pregnancy.

Based on pattern recognition theory and support vector machine (SVM) network technology, automatic detection, location, segmentation and recognition of license plates characters are discussed in detail. A new method is presented to adopt gray-grads, shape and posture, vision model and so on. And a new multi-sorts classification method - binary exponent classification is proposed. By comparing least squares support vector machines (LS-SVM) with BP neural network in vehicle license plates pattern recognition and classification, Experimental results showed that SVM is more convenient, fast and nicely of judgment, and will be the mainstream of the future development in the application of finite sample data pattern recognition

The authors show that oscillations at foetal breathing frequencies observed in foetal heart rate (FHR) tracings obtained from foetal magnetocardiogram (FMCG) recordings are often accompanied by synchronous modulation of FMCG signal amplitude. This implies an association between the FHR oscillations and foetal chest wall movements, corroborating the hypothesis that the oscillations are due to respiratory sinus arrhythmia.

We describe the development of computer visualization tools that display topographic maps of neuromagnetic data on a realistic head shape. Two topographic display modes are implemented — a "raw" mode that shows the actual position and orientation of the detection coils with respect to the head shape, as well as the magnetic field sensed by each coil, and a "cooked" mode, where the magnetic data is interpolated onto the scalp. False coloration is used to represent magnetic field strength. The topographic displays are combined with waveform displays in order to integrate spatial and temporal visualization of the data. Dipole fitting routines have also been incorporated into the software.

We have measured fetal magneto-cardiograms in three subjects of gestation ages 33–37 weeks. Maternal interference was negligible in all recordings. Accurate measures of heart rate, beat-to-beat variability, and averaged MCG waveforms were derived. The results confirm that magnetic monitoring offers significant advantages for antepartum monitoring and deserves further investigation.