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Background Malignant pleural mesothelioma (MPM) is a rare tumor in the pleura. This study was carried out to identify key genes and pathways that may be involved in MPM. Methods Microarray datasets GSE51024 and GSE2549 were analyzed for differentially expressed genes (DEGs) between normal and MPM tissues. The identified DEGs were subjected to functional analyses using bioinformatics tools. Results A total of 276 DEGs were identified, consisting of 187 downregulated and 79 upregulated genes. Gene ontology and Kyoto encyclopedia of genes and genomes pathway enrichment analysis indicated that the DEGs were enriched in extracellular structure organization, extracellular matrix, and ECM−receptor interaction. Due to high degree of connectivity among 24 hub genes, EZH2 and HMMR are likely to play roles in the carcinogenesis and progression of MPM. The two genes were found over-expressed in MPM tissues. Patients with elevated EZH2 and HMMR expressions had poor overall survival. Conclusions EZH2 and HMMR are identified to be the hub genes for MPM and they may be further characterized to better understand the molecular mechanisms underlying the carcinogenesis of MPM.

Purpose To compare clinicopathologic factors including tumor-node-metastasis (TNM) stage between young and elderly patients with non-small cell lung cancer (NSCLC). Methods This retrospective study compared the following characteristics between 52 young patients with NSCLC ( 60 years): duration of symptoms before medical consultation, smoking index, family history of cancer, Ki-67 index, and pTNM stage. A binary logistic regression analysis was used to identify factors predictive of greater stage NSCLC (stage III/IV compared to stage I/II) within each age group. Results The incidence of adenocarcinoma was higher in the young than in the elderly (P=0.006). Smoking index (P=0.002) and Ki-67 index (P

The rise of heteromorphic architecture brings great challenges to engineering design, blanking, construction, completion testing, and maintenance. The 3D laser scanning measurement technology can quickly achieve the “copy” measurement of the target, especially suitable for the digitization of complex structure and the accurate construction of true 3D model and it takes care of other things which are necessary environment point of view. In this paper, we are considering the steel structure inspection and curtain wall blanking in the construction of the Grand Theater in the “Shangqiu Cultural and Art Center” as a case study. First, the laser scanning technology has been introduced to complete the data acquisition of steel structure objects and to screen the other details of the structure. Then, the high-quality point cloud is obtained through multistation splicing, filtering, denoising and smoothing, compression, and simplification. Through field comparison, the point cloud accuracy reached an acceptable level. Through field comparison, it can be seen that the difference between the designed building model combining laser technology and BIM technology is distributed within the range of ±(1–5)mm, and the mean square error is ±3.5 mm, and the deviation of numerical simulation is small, which meets the building requirements. Therefore, this method can effectively detect steel structure, and the BIM model can be updated according to the measured point cloud data. We provide accurate data reference for curtain wall material and installation.

In this work, a visual colorimetric method for the rapid and selective detection of triacetone triperoxide is reported. This visual colorimetric method is based on the reaction between potassium titanyl oxalate and hydrogen peroxide (H2O2) released from triacetone triperoxide degradation. Potassium titanyl oxalate can selectively react with H2O2 to form peroxo-titanic acid (an orange complex), enabling the colorimetric detection of triacetone triperoxide. Based on the theory that triacetone triperoxide produces hydrogen peroxide under acidic conditions, acid types, acid concentration, response time, visual limit of detection, and reactants ratio are systematically studied simultaneously for this colorimetric method. Under sulfuric acid concentration is 60%, the proposed method can almost detect triacetone triperoxide instantly, and the color of the solution reaches the maximum within 1 min and remains stable with a visual limit of detection as low as 3.0 × 10−5 mol/L. Interference experiments were carried out on other kinds of explosives (hexamethylene triperoxide diamine, trinitrotoluene, etc.). The use of colorimetric card brings great convenience to the rapid, qualitative, and semi-quantitative on-site detection of triacetone triperoxide. Because of its rapidity, high sensitivity, simplicity, and selectivity, the proposed visual colorimetric method can serve as a valuable and promising reference for triacetone triperoxide’s rapid, qualitative on-site detection.

We wished to construct a prognostic model based on ferroptosis-related genes and to simultaneously evaluate the performance of the prognostic model and analyze differences between high-risk and low-risk groups at all levels. The gene-expression profiles and relevant clinical data of patients with non-small-cell lung cancer (NSCLC) were downloaded from public databases. Differentially expressed genes (DEGs) were obtained by analyzing differences between cancer tissues and paracancerous tissues, and common genes between DEGs and ferroptosis-related genes were identified as candidate ferroptosis-related genes. Next, a risk-score model was constructed using univariate Cox analysis and least absolute shrinkage and selection operator (Lasso) analysis. According to the median risk score, samples were divided into high-risk and low-risk groups, and a series of bioinformatics analyses were conducted to verify the predictive ability of the model. Single-sample gene set enrichment analysis (ssGSEA) was used to investigate differences in immune status between high-risk and low-risk groups, and differences in gene mutations between the two groups were investigated. A risk-score model was constructed based on 21 ferroptosis-related genes. A Kaplan–Meier curve and receiver operating characteristic curve showed that the model had good prediction ability. Univariate and multivariate Cox analyses revealed that ferroptosis-related genes associated with the prognosis may be used as independent prognostic factors for the overall survival time of NSCLC patients. The pathways enriched with DEGs in low-risk and high-risk groups were analyzed, and the enriched pathways were correlated significantly with immunosuppressive status.

We present a three-dimensional (3D) imaging system that incorporates a stationary camera and Risley prisms. By planning prism rotation to generate a spatially adaptive virtual camera field, the system allows multiple virtual cameras in the field to capture any object from different perspectives for 3D reconstruction. An automatic virtual camera calibration method based on perspective projection and geometric optics is developed to enable virtual camera field construction and characterization. Moreover, a 3D computational reconstruction framework is proposed for multiview information fusion using the virtual camera field. This framework combines nonlinear distortion correction with epipolar geometry computation to efficiently perform image rectification and stereo matching, which can further facilitate 3D object reconstruction through multiview triangulation. The experiments on synthetic and real data validate the feasibility and flexibility of our 3D imaging technique.

Purpose To compare clinicopathologic factors including tumor-node-metastasis (TNM) stage between young and elderly patients with non-small cell lung cancer (NSCLC). Methods This retrospective study compared the following characteristics between 52 young patients with NSCLC (60 years): duration of symptoms before medical consultation, smoking index, family history of cancer, Ki-67 index, and pTNM stage. A binary logistic regression analysis was used to identify factors predictive of greater stage NSCLC (stage III/IV compared to stage I/II) within each age group. Results The incidence of adenocarcinoma was higher in the young than in the elderly (P=0.006). Smoking index (P=0.002) and Ki-67 index (P

Fast imaging tracking technology exhibits attractive application prospects in the emerging fields of target tracking and recognition. Smart and compact tracking model with fast and flexible tracking strategy can play a decisive role in improving system performance. In this paper, an effective imaging tracking model from a target to a rotation Risley prism pair embedded with a camera is derived by the beam vector propagation method. A boresight adjustment strategy using the inverse ray tracing and iterative refinement method is established to accomplish the function of fast locating a target. The influence of system parameters on boresight adjustment accuracy and even the dynamic characteristics of the tracking system are investigated to reveal the coupling mechanisms between prism rotation and imaging feedback. The root-mean-square tracking error is below 4.5 pixels by just once adjustment in the static target experiment, while the error in the dynamic experiment is below 8.5 pixels for a target moving at the speed of 50 mm/s, which validates the feasibility of the proposed method for fast imaging tracking applications.

Scan blind zone and control singularity are two adverse issues for the beam scanning performance in double-prism Risley systems. In this paper, a theoretical model which introduces a third prism is developed. The critical condition for a fully eliminated scan blind zone is determined through a geometric derivation, providing several useful formulae for three-Risley-prism system design. Moreover, inverse solutions for a three-prism system are established, based on the damped least-squares iterative refinement by a forward ray tracing method. It is shown that the efficiency of this iterative calculation of the inverse solutions can be greatly enhanced by a numerical differentiation method. In order to overcome the control singularity problem, the motion law of any one prism in a three-prism system needs to be conditioned, resulting in continuous and steady motion profiles for the other two prisms.

In this paper, the packaging-induced stresses are theoretically calculated by modeling multilayered structures for different packaging structures. We report a method to measure the packaging-induced stress of a laser diode array (LDA) by comparing the emission wavelength of the single emitter located in the middle of a laser bar before and after packaging. The wavelength is tested under a low duty cycle (50 μs/10 Hz, DC 0.05%) to eliminate the thermal effect to wavelength shifting. Experimental calculation results for the packaging-induced stress of LDAs are in good agreement with the theoretical calculations and simulation results. For a GaAs laser bar, we find the packaging stresses are compression stresses, which make the emission wavelength blue-shift in terms of 1.09×10−2 nm/MPa. We propose a mapping of packaging-induced stress distribution in laser bars on a microscopic scale by considering the emission spectra of each emitter in a laser bar. Compared to single-emitter resolved photo-current or micro-photoluminescence measurements, as proposed by other authors, we offer a much easier tool to test and map the distribution of packaging-induced stress in laser bars.

In this paper, 3-D, steady-state, analytical thermal models of high-power single-emitter semiconductor lasers (SEs) and laser diode arrays (LDAs) are derived, considering the heat conduction in multi-layered laser structures. Heat flow in the laser chips for an epi-down bonded SE and LDA is described using this model, and it is observed that the laser chips contribute to 8% and 6% of total heat dissipation for the SE and LDA, respectively. The submount size requirement for this model is discussed by revealing the heat flow in the submount. Through finite element simulations, the solution accuracy for the lasers with non-ideal submounts is confirmed. Finally, the performance of our proposed analytical models is verified by finite element simulations and experimental measurements based on the wavelength shift method.

Near-field bowing a laser diode bar (i.e., the "SMILE" effect) degrades the laser beam brightness, adversely affecting optical coupling and beam shaping. Due to thermally induced stress during the bonding process, the emitters in a laser diode array (LDA) are vertically displaced, which causes the SMILE effect. The mismatch between the coefficients of thermal expansion of an LDA (GaAs with 6.4 ppm/K) and a heat sink (Cu with 16.4 ppm/K) is a large obstacle in the LDA bonding process, because it provokes thermal stress and a large SMILE value, resulting in a larger divergence angle and a wider line after focusing and collimation. In this paper, the changes in stress and strain (SMILE value) and their effects on the laser bar as a function of the copper-tungsten (CuW) submount thickness were theoretically and experimentally studied. The finite element modeling simulations and experimental results show that the compression stress on the laser bar decreases with increasing CuW submount thickness because the CuW submount works as a buffer layer and can absorb stress. However, the laser bar out-of-plane strain (SMILE value) is approximately zero when the LDA is directly bonded onto the heat sink without a submount; the SMILE value is maximized when the CuW submount thickness is increased to approximately one half or 44% of the heat sink. Beyond that, the SMILE value decreases with increasing CuW submount thickness.

In this paper, the error analysis model for the three-element Risley-prism scan system (TRSS) is established, and categories of error sources are redefined. The impact of each error on the pointing accuracy is graphically presented with analytical and numerical results. The analysis method can be implemented to any Risley-prism beam scan system. For thin prisms, an error compensation algorithm for the TRSS is developed to accomplish high-accuracy beam scanning, which can be referred to the error calibration of the TRSS.

Spectral-width broadening has many factors. Diode lasers are not always monochromatic due to several broadening mechanisms, widening the energy distribution of emitted photons. In this paper, we report the two main factors affecting time average spectral-width broadening of a laser diode array (LDA)-a transient rise of the active region temperature of an LDA due to injection current, and the temperature and stress nonuniform distribution of different emitters within an LDA. We find that temperature and stress nonuniformity broadens the spectral width by almost 0.1-1.0 nm as a function of different operating conditions, while the thermally induced chirp that is attributed to injection current plays a more signification role in spectral-width broadening.

A cleaner process for synthesis of zeolite MCM-22 by vapor-phase transport method was studied in this paper. Firstly, zeolite MCM-22 was synthesized at different hexamethyleneimine (HMI) dosages by vapor-phase transport (VPT) method. It was concluded that the aluminosilicate gel was not crystallized completely and the product crystallinity was low when the HMI/gel mass ratio was

Self-bonded bodies of zeolite MCM-22 were prepared by vapor-phase transport method. The resultant materials were characterized by means of X-ray diffraction, scanning electron microscope, mercury porosimetry, and nitrogen porosimetry. Self-bonded MCM-22 bodies were in situ prepared at pH 10.0 with the molar composition of 0.05Na2O:SiO2:0.033Al2O3. It was found that the bodies, prepared by aluminosilicate gel, had been transformed into zeolite MCM-22. The MCM-22 bodies of which the mechanical resistance was 126 N/cm avoided binder accession. By adding auxiliary chemical–PEG20000 to the aluminosilicate gel, the pore size distributions of MCM-22 bodies could be adjusted. The average pore radius of MCM-22 bodies reached in the 149.41–653.64 nm range when AC/SiO2 ratio was 1.5 × 10−4–9.0 × 10−4.

Self-bonded bodies of zeolite MCM-22 were prepared by vapor-phase transport method. The resultant materials were characterized by means of XRD, SEM, NH3-TPD, BET, 27Al MAS NMR, Pascal 140 and Pascal 240. It was found that the bodies, prepared by aluminosilicate gel, had been transformed into zeolite MCM-22. The zeolite bodies that were composed of MCM-22 crystal chips avoided binder accession. The total acid sites, the specific surface area, mechanical resistance and the average pore radius of the zeolite bodies reached 1.01 × 10−3 mol/g, 486.82 m2/g, 126 N/cm and 57.93 nm, respectively.

Solder joint fatigue failure is a serious reliability concern in area array technologies, such as flip chip and ball grid array packages of integrated-circuit chips. The selection of different substrate materials could affect solder joint thermal fatigue life significantly. The reliability of solder joints in real flip chip assembly with both rigid and compliant substrates was evaluated by the accelerated temperature cycling test and thermal mechanical analysis. The mechanism of substrate flexibility on improving solder joint thermal fatigue lifetime was investigated by fracture mechanics methods. Two different methods (crack tip opening displacement, CTOD and virtual crack closure technique, VCCT) are used to determine the crack tip parameters which are considered as the indices of reliability of solder joints, including the strain energy release rate and phase angle for the different crack lengths and temperatures. It was found that the thermal fatigue lifetime of solder joints in flip chip on flex assembly (FCOF) was much longer than that of flip chip on rigid board assembly (FCOB). The flex substrates could dissipate energy that otherwise would be absorbed by solder joints, that is, substrate flexibility has a great effect on solder joint reliability and the reliability improvement was attributed to flex buckling or bending during thermal cycling.

Abnormal spectral characteristics are observed in high-power semiconductor pump laser modules with ultralow chip front-facet reflectivity levels. We have identified the root cause as destructive interference in an external-cavity reflection from an antireflection (AR) coated fiber tip. This suppressive external cavity imposes a practical limit on the lower desirable bound for front-facet AR coatings for high-power lasers and uncooled fiber Bragg grating stabilized semiconductor devices.

A parasitic-free technique using outband optical modulation for measuring a semiconductor optical amplifier's (SOA's) dynamic response is proposed. It is demonstrated that a counter-propagating scheme is useful in measuring the carrier lifetimes and the response obtained with a co-propagating scheme includes the transmission function of an SOA.

The use of a thick quantum well enables coherence-collapse operation of a Bragg grating stabilised laser diode over 110°C temperature range, yielding 975 nm wavelength emission with >40 dB sidemode suppression ratio

High efficiency continuous-wave operation of 1.53 /spl mu/m vertical cavity surface emitting lasers (VCSELs) with buried tunnel junction grown by metal organic chemical vapour deposition (MOCVD) has been demonstrated. Devices show a high differential quantum efficiency of 46% and a singlemode power of 1 mW. Minimum threshold current and voltage are 0.45 mA and 1.3 V at room temperature, respectively for devices of 5 /spl mu/m diameter.