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Study objectives Sleep is associated with a reduction in ventilation and an increase in upper airway resistance (UAR) in patients with obstructive sleep apnea (OSA). However, there is no consensus on the standard for assessment of UAR and therefore it is important to develop a method to reliably assess UAR in patients with OSA. The purpose of the present study is to determine whether the ratio of neural respiratory drive (NRD) to flow can be used to assess changes in UAR in OSA during sleep. Methods A total of 24 patients (21 men) with OSA and 10 normal subjects (6 males) were studied. The UAR was assessed by the ratio of NRD to flow, which measured by esophageal pressure (Poes), diaphragm electromyography (EMGdi) and superficial diaphragm electromyography (SEMGdi) in various stages including wakefulness, N2 sleep, N2 sleep with snoring, hypopneas, the in the “preapnea” states in OSA versus wakefulness, sleeponset, N2 sleep, N3 sleep in normal subjects. All subjects underwent overnight full polysomnography using standard techniques. Results Our study indicate that UAR was progressively higher from wakefulness to N2 sleep, N2 sleep with snoring, hypopneas, and the in the “preapnea” states in patients with OSA and had obvious difference in statistical significance (p Conclusions It is feasible to use the ratio of neural respiratory drive to flow to assess UAR in patients with OSA during sleep.

In the construction of English teachers’ classroom competence system, traditional evaluation methods are incomplete in data collection, inaccurate in classification and insufficient in decision-making basis. Therefore, this paper introduced the K-means clustering algorithm in artificial intelligence algorithm to evaluate the English teaching ability. Based on the research of the K-means clustering algorithm and the implementation method, a fuzzy clustering algorithm combined with big data and information analysis is established to cluster various indicators in the English teaching ability system, which is the basis for improving teaching plan and evaluating teaching ability. It is proved by the simulation experiment that the evaluation of the English teaching ability is more accurate, and the scientific nature of the construction of the teaching ability system is effectively improved.

The use of traditional chemical insecticides for pest control often leads to environmental pollution and a decrease in biodiversity. Recently, insect sex pheromones were applied for sustainable biocontrol of pests in fields, due to their limited adverse impacts on biodiversity and food safety compared to that of other conventional insecticides. However, the structures of insect pheromones are complex, and their chemical synthesis is not commercially feasible. As yeasts have been widely used for fatty acid-derived pheromone production in the past few years, using engineered yeasts may be promising and sustainable for the low-cost production of fatty acid-derived pheromones. The primary fatty acids produced by Saccharomyces cerevisiae and other yeasts are C16 and C18, and it is also possible to rewire/reprogram the metabolic flux for other fatty acids or fatty acid derivatives. This review summarizes the fatty acid biosynthetic pathway in S. cerevisiae and recent progress in yeast engineering in terms of metabolic engineering and synthetic biology strategies to produce insect pheromones. In the future, insect pheromones produced by yeasts might provide an eco-friendly pest control method in agricultural fields.

The mismatch between energy distribution and power load in China can be alleviated by inter-regional and inter-provincial power transactions. However, it also brings challenges to transaction settlement. In the new round of electric power reform, the transaction settlement deviation quantity needs to be more standardized. Based on the analysis of the related work, this article used the analytical framework of the analytic hierarchy process to calculate the transaction type weight, the inter-regional, and the inter-provincial weight, respectively, and accordingly, quantifies the amount of deviation quantity allocated by the corresponding trading subjects. According to the size and volatility of the trading quantity, we further propose a comprehensive weighting method based on kernel density and entropy weight to quantify the deviation quantity of inter-regional and inter-provincial trading subjects of different trading types. Specifically, this article first used the kernel function weighting method to calculate the weights of different transaction types that measure the transaction quantity, and then the improved entropy weight method was used to calculate the weights of different transaction types that reflect the volatility of the transaction quantity. Then, the comprehensive weights were constructed by considering the influence of the above two dimensions on the distribution of the deviation electricity simultaneously. The deviation electricity responsibility determination model was used to clarify the transaction subject's deviated electricity responsibility, and the deviated electric quantity calculation model was used for quantification. At last, the validity and practicability of the method were verified through the analysis of examples using the inter-regional and inter-provincial power transaction data from China.

The efficient yellow phosphors with broad emission bandwidths play quite important roles in the realization of high-performance two-color white organic light-emitting devices (OLEDs). Herein, by using a chlorine-functionalization method, we designed three efficient yellow iridium(III) complexes (Ir1–Ir3 ) bearing chlorine atoms. At room temperature, these phosphors exhibit bright yellow phosphorescence with emission wavelengths of 549–574 nm and high photoluminescence efficiency of 0.49–0.73 in the N 2 -saturated dichloromethane. Importantly, these complexes feature extremely broad emission bandwidths (reaching 104 nm), making them the record-high values in the yellow iridium(III) phosphors reported so far. Using these complexes as the triplet dopants , the prepared OLEDs show yellow phosphorescence with the emission maximum at 565, 548, and 551 nm, respectively. The extremely high external quantum efficiency of 23.8% was realized for the as-prepared yellow OLEDs. Furthermore, Ir2 -based two-color white OLED with high spectral quality was also realized, and the color rendering index and CIE coordinates for two-color white OLED are 74 and (0.32, 0.34), respectively. The broad yellow emission band and high-efficiency of the device proved that these phosphors show great potentials in developing high-performance yellow and white electroluminescence .

In the preliminary design stage of the full form ships, in order to obtain a hull form with low resistance and maximum propulsion efficiency, an optimization design program for a full form ship with the minimum thrust deduction factor has been developed, which combined the potential flow theory and boundary layer theory with the optimization technique. In the optimization process, the Sequential Unconstrained Minimization Technique (SUMT) interior point method of Nonlinear Programming (NLP) was proposed with the minimum thrust deduction factor as the objective function. An appropriate displacement is a basic constraint condition, and the boundary layer separation is an additional one. The parameters of the hull form modification function are used as design variables. At last, the numerical optimization example for lines of after-body of 50000 DWT product oil tanker was provided, which indicated that the propulsion efficiency was improved distinctly by this optimal design method.

The objective of this study is to detect the p66shc mRNA and protein expression of the peripheral blood monocytes (PBMs) in coronary heart disease patients (CHD) and controls, to evaluate the correlation between the expression of p66shc mRNA in the PBMs and endothelium-dependent vasodilatation. This study included 78 coronary angiography-documented CHD patients (CHD group) and 38 non-CHD controls (control group). The p66shc mRNA and protein levels were determined by quantitative real-time PCR and western blotting. The flow-mediated dilatation (FMD, endothelium-dependent), nitroglycerine-induced dilatation (NID, endothelium-independent) and carotid intimal medial thickness (CIMT) were detected using high-resolution ultrasound. The p66shc mRNA and the protein expression levels in the PBMs were significantly higher in the CHD group compared with the control group (p = 0.007 and 0.001). The FMD (p < 0.001) and NID (p = 0.013) were significantly lower and the CIMT (p = 0.007) was significantly thicker in the CHD patients than in the controls. In the univariate analysis, the expression of the p66shc mRNA in the PBMs was significantly positively correlated with the serum LDL-C and homocysteine levels and the CIMT and was inversely correlated with the FMD and the NID (all p < 0.001). In the multiple linear regression analysis, the FMD (p < 0.001), LDL-C (p = 0.002) and homocysteine levels (p = 0.002) remained independently correlated with the p66shc mRNA expression. These findings highlight a pivotal role for the expression of p66shc in CHD and endothelial dysfunction, which might represent a molecular target to prevent endothelial dysfunction-related disease.

The rapid process design technology about box parts based on 3D model was researched in this paper, in order to analyze process feature, it has broken through key technology for obtaining 3D process knowledge from the process knowledge database. The process knowledge sharing and technique process optimization were realized. It shortens the preparation cycle of process of new product development.

Optical coherence tomography (OCT) based on a wave front division (WD) interferometer is demonstrated for the first time. Unlike a conventional amplitude division interferometer based OCT, WD OCT utilizes different wave front portions of the light source for sample and reference arm. Due to easy manipulation of the wavefront portions for sample and reference arm, it is feasible for WD OCT, provided that the source power of light is fixed, to optimize the ratio of light power for sample and reference arm to achieve both high power efficiency and high system sensitivity. The system sensitivity as a function of the ratio of light power directed to the two arms is experimentally studied and the result found to be well consistent with the theoretical analysis. In our current time-domain WD OCT, we have achieved the system sensitivity as high as 115 dB at a total source power of only 7.5 mW with 8% to the reference arm. Real-time WD OCT imaging of bio-tissues in vivo is also demonstrated.

Absorption dyes are widely used in traditional cytology and pathology clinical practice, while fluorophores and nanoparticles are more often used in biologic research. Optical projection tomographic microscopy (OPTM) is a platform technology that can image the same specimen in multiple modes in 3D, providing morphologic and molecular information concurrently and in exact co-registration. The depth-of-field of a high numerical aperture objective is extended by scanning the focal plane through the sample to generate an optical projection image. Samples of cells or tissue are brought into the OPTM instrument through a microcapillary tube filled with optical index-matching gel. Multiple optical projection images are taken from different perspectives by rotating the tube. Computed tomography (CT) algorithms are applied to these optical projection images to reconstruct 3D structure of the sample. Image segmentation and analysis based on these 3D images provide quantitative biosignatures for cancer diagnosis that represents a clear improvement over conventional 2D image analysis. In this article, we introduce the OPTM platform, optical Cell-CT, and Tissue-CT instruments, and some applications using these OPTM instruments.

Cu2ZnSnS4(CZTS) film was prepared by screen printing process with the advantages of simple, high-effective and cost-effective. The annealing effects on the screen printed CZTS films were studied. It was found that the crystallinity of the CZTS can be effectively improved by the annealing process, whereas overlong annealing can also introduce defects to the CZTS. The bandgap value of the CZTS is about 1.4 eV. The short-circuit current density, open-circuit voltage, fill factor and conversion efficiency of the best solar cell with superstrate structure of Carbon/CZTS/In2S3/TiO2/FTO glass (without using any vacuum conditions) are 6.20 mA/cm2, 290 mV, 0.29 and 0.53%, respectively.

Partial wave spectroscopy (PWS) enables quantification of the statistical properties of cell structures at the nanoscale, which has been used to identify patients harboring premalignant tumors by interrogating easily accessible sites distant from location of the lesion. Due to its high sensitivity, cells that are well preserved need to be selected from the smear images for further analysis. To date, such cell selection has been done manually. This is time-consuming, is labor-intensive, is vulnerable to bias, and has considerable inter- and intraoperator variability. In this study, we developed a classification scheme to identify and remove the corrupted cells or debris that are of no diagnostic value from raw smear images. The slide of smear sample is digitized by acquiring and stitching low-magnification transmission. Objects are then extracted from these images through segmentation algorithms. A training-set is created by manually classifying objects as suitable or unsuitable. A feature-set is created by quantifying a large number of features for each object. The training-set and feature-set are used to train a selection algorithm using Support Vector Machine (SVM) classifiers. We show that the selection algorithm achieves an error rate of 93% with a sensitivity of 95%.

Conventional Optical Projection Tomography (OPT) can image tissue samples both in absorption and fluorescence mode. Absorption image can show the anatomical structure of the sample, while fluorescence mode can determine specific molecular distribution. The depth of focus (DOF) of the lens in conventional OPT needs to transverse the whole sample. As a result, resolution will be poor due to the low numerical aperture (NA) needed to generate large DOF. In conventional pathology, the specimens are embedded in wax and sliced into thin slices so that high NA objective lens can be used to image the sections. In this case, the high resolution is obtained by using high NA objective lens, but 3D images can be only obtained by stitching different sections together. Here, we propose a new method that can image entire specimen without sectioning with the same high resolution as the conventional pathology. To produce high resolution that is isotropic, the original OPTM system scans the focal plane of the high NA objective through the entire specimen to produce one projection image. Then the specimen is rotated so that the subsequent projection is taken at different perspective. After all the projections are taken, 3D images are generated by the filtered back-projection method. However, the scanning rate is limited by scanning objective lens due to the large mass of the lens. Here we show a new OPTM system that scans the mirror in the conjugate image space of the object to produce projections.

Phase-contrast imaging in the x-ray regime has become increasingly appealing for medical and security applications. I will review techniques for recovery under sparsity priors, and describe some key results demonstrating the value of this approach.

We develop a compressive reconstruction method for tomographic reconstruction of refractive index distribution of weakly attenuating objects using the transport of intensity imaging in a microfocus X-ray system.

Optical projection tomography (OPT) requires the depth of field (DOF) of the lens to cover at least half of the sample. There is a trade-off between obtaining high resolution with a high-NA lens and obtaining large DOF with a low-NA lens. The DOF of a high-NA objective lens can be extended by scanning its focal plane through the sample. We call this extended DOF image a “pseudoprojection.” Images reconstructed from these pseudoprojections have isometric resolution, which can be the same as the lateral resolution of the high-NA objective. The focal scanning method produces an over 10× improvement in OPT resolution.

An optical projection tomography microscope (OPTM) can improve axial resolution by viewing a sample from different perspectives. Here, we report a dual-mode OPTM that can generate 3D images of single cancer cells in both absorption mode and polarization mode. Cancer cells were labeled with hematoxylin for absorption imaging and nanorods for polarization imaging. Absorption images can provide morphologic information, and polarization images can provide molecular information. The combination of molecular detection and 3D cytological cell analysis may help with early cancer diagnosis.

A dual-modal optical projection tomography microscope (OPTM) is presented, which produces three-dimensional images of single cells with isometric high resolution both in fluorescence and absorption mode. Depth of field of a high numerical aperture objective is extended by scanning the focal plane through the sample in order to enable reconstruction by back-projection method. Cells are fixed, stained, and mixed with optical gel and injected into the capillary for imaging. Combining absorption and fluorescence mode allows us to image different aspects of the disease process. Images of cells stained with both hematoxylin and fluorescence probes are shown. Registrations between two modes are discussed.

The optical projection tomography microscope (OPTM) is an optical microscope that acquires focus-invariant images from multiple views of single cells. Although the depth of field of the objective is short, it can be extended by scanning the objective's focal plane. This extended depth of field image is similar to a projection in conventional X-ray CT. Samples flow through a microcapillary tube filled with optical gel. Optical distortion is minimized by matching refractive index of optical gel and tube. Multiple projection images are taken by rotating the microcapillary tube with sub-micron mechanical precision. After these pseudoprojection images are further aligned, computed tomography methods are then applied to the images to create a 3D reconstruction with isometric resolution of 0.35 microns. Three-dimensional reconstructed images of fluorescent microspheres and cells are shown.

The optical projection tomography microscope (OPTM) acquires three-dimensional images with isometric high resolution both in absorption and fluorescence modes, employing computed tomographic image reconstruction. The three-dimensional chromosome structure of a female muntjac cell is shown.

A power-conserving wave-front division Fourier domain optical coherence tomography (WD FDOCT) has been successfully demonstrated. Unlike conventional Michelson-based FDOCT system, splitting ratio of WD FDOCT can be arbitrarily adjusted to enhance signal-to-noise ratio (SNR). Both theoretical and experimental SNR of this system are evaluated. WD FDOCT imaging of the anterior eye of a rat is also demonstrated.

In this paper, the mathematic model of receiver about electromagnetic compatibility is described. The basic process about effectiveness evaluation is given, and receiver models on every evaluation process are built.

We develop and implement a compressive reconstruction method for tomographic recovery of refractive index distribution for weakly attenuating objects in a microfocus x-ray system. This is achieved through the development of a discretized operator modeling both the transport of intensity equation and the x-ray transform that is suitable for iterative reconstruction techniques.

The practice of clinical cytology relies on bright-field microscopy using absorption dyes like hematoxylin and eosin in the transmission mode, while the practice of research microscopy relies on fluorescence microscopy in the epi-illumination mode. The optical projection tomography microscope is an optical microscope that can generate 3-D images of single cells with isometric high resolution both in absorption and fluorescence mode. Although the depth of field of the microscope objective is in the submicron range, it can be extended by scanning the objective's focal plane. The extended depth of field image is similar to a projection in a conventional x-ray computed tomography. Cells suspended in optical gel flow through a custom-designed microcapillary. Multiple pseudoprojection images are taken by rotating the microcapillary. After these pseudoprojection images are further aligned, computed tomography methods are applied to create 3-D reconstruction. 3-D reconstructed images of single cells are shown in both absorption and fluorescence mode. Fluorescence spatial resolution is measured at 0.35 microm in both axial and lateral dimensions. Since fluorescence and absorption images are taken in two different rotations, mechanical error may cause misalignment of 3-D images. This mechanical error is estimated to be within the resolution of the system.

Previous studies on either animal model or clinical settings have demonstrated that the expression of AML1/ETO9a (AE9a), a truncated version of AML1-ETO (AE) generated by alternative splicing during transcription, in patients with acute myeloid leukemia M2 subtype may have clinical significance. Moreover, the simultaneously expression of both AE and AE9a may even be more meaningful to the prognosis of the patients. To validate this hypothesis, we have measured the mRNA level of both AE and AE9a in each individual M2 patient by quantitative real-time RT-PCR, and correlated the ratio of AE/AE9a mRNA levels with the clinical outcome and prognosis in these patients. In 35 newly-diagnosed AML-M2 patients with t(8;21), expression of AE9a was detected in 30 cases (85.71%). The median value of the percentages of AE9a and AE within overall transcripts of the fusion gene in these patients were 18.16% and 81.84%, respectively (p

Optical Coherence Tomography (OCT) is a new technique mainly used in biomedical imaging. We present here a Particle-Fixed Monte Carlo (PFMC) simulation for OCT signal. In the PFMC model, the scattering particles of the sample are assumed to be temporarily fixed and randomly distributed in the simulation of the backscattered light. An efficient partitioning scheme is proposed to speed up this simulation process. The new model explains the exponential decay signal at the interfaces of different media layers observed in OCT experimental measurements.

Background: This study investigated the correlation of lipoprotein-associated phospholipase A2 (Lp-PLA2) levels with angiographic coronary artery disease, the extent of angiographic coronary artery lesions and coronary artery disease risk factors in the elderly. Methods: Plasma Lp-PLA2, lipid, and high-sensitivity C-reactive protein levels were measured in 192 elderly patients who underwent coronary angiography because of suspected coronary artery disease. The extent of coronary artery lesions was recorded according to the number of vessels with lesions and the Gensini score system. The relationships of Lp-PLA2 with angiographic coronary artery disease, the extent of coronary artery lesions, and associated risk factors were assessed. Results: Plasma Lp-PLA2 (359.56 ± 133.47 μg/L vs. 215.12 ± 58.93 μg/L, p