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Exploring the changes in intracellular viscosity in response to inflammatory stress is of great significance for the detection and treatment of various diseases.

In order to reconstruct the wavefront of reception diversity atmospheric laser communication, the paper first improves the reconstructing modal method of traditional single-input-single-output laser communication based on mutual information. Because the distortion wavefront caused by atmospheric turbulence is a fractal surface of Fractional Brownian motion, a fast wavefront reconstructing method of reception diversity atmospheric laser communication is proposed in this paper. The result shows that the wavefront reconstructing method based on mutual information can optimize the reconstructing performance effectively. Besides, the running time of proposed reconstructing method of reception diversity atmospheric laser communication decreases greatly. Through the comparison of generated wavefront and reconstructed wavefront, the feasibility of the proposed method is demonstrated. It proves that the wavefront reconstructed by proposed method based on Fractional Brownian motion can fit the theory well through the comparison of phase structure function.

Camel milk (CM) is considered to protect the liver in the practice of traditional medicine in nomadic areas. The purpose of the present study was to investigate the effects of CM on the hepatic biochemical and multiple omics alterations induced by chronic alcoholic liver disease (ALD). An intragastric gavage mice Lieber DeCarli + Gao binge model (NIAAA model) was employed to investigate the inflammatory mechanism of camel milk on the liver tissue of mice. A gut microbiota of the feces of mice and transcriptomic and proteomic analyses of the liver of mice were performed. Analysis of serum and liver biochemical indexes revealed that camel milk not only prevents alcohol-induced colonic dysfunction and lipid accumulation, but also regulates oxidative stress and inflammatory cytokine production to protect against chronic ALD in mouse. The gut microbial community of mice treated with camel milk was more similar to the untreated control group than to the model group, indicating that the intake of camel milk pre- and post-alcohol gavage effectively prevents and alleviates the intestinal microbial disorder caused by chronic alcoholism in mice. Furthermore, the results of the transcriptomic and proteomic analyses of the liver tissue showed that camel milk can improve alcoholic liver injury in mice by regulating inflammatory factors and immune system disruptions. This study provides insights into the molecular mechanism by which camel milk can be developed as a potential functional food with no side effects and against liver injury.

We propose an orbital angular momentum (OAM) state detection method based on diffractive deep neural network (D2NN). The correct classification of the topological charge (TC) of the range [ ± 1, ± 2, …, ± 10] is implement. Based on the designed phase-only, amplitude-only and hybrid type network, we analyzed the influence of the number of diffractive layers and the strength of turbulence on the detection accuracy. The results show that the method can realize the rapid detection of OAM state, which has potential value for free space optical (FSO) communication based on optical vortex (OV) beam.

The phase screen method is a well-established approach to analyze the effects of atmospheric turbulence in free space optical (FSO) communication and astronomical imaging system. Owning to the variation of atmospheric turbulence, low complexity modeling is required. Meanwhile, low frequency power should be compensated to overcome shortcomings of classical methods. The method based on sub-bands division and multirate sampling is proposed to solve these problems, and analytic formulas of the model is derived correspondingly. Simulation results are provided to show that our method overperforms the existing methods when both computational complexity and power compensation are taken into account. Furthermore, the proposed method is flexibly in operating which could be used to simulate the base phase screen of time-varying atmospheric turbulence.

Existing wavefront reconstruction methods are usually low in resolution, restricted by structure characteristics of the Shack Hartmann wavefront sensor (SH WFS) and the deformable mirror (DM) in the adaptive optics (AO) system, thus, resulting in weak homodyne detection efficiency for free space optical (FSO) communication. In order to solve this problem, we firstly validate the feasibility of liquid crystal spatial light modulator (LC SLM) using in an AO system. Then, wavefront reconstruction method based on wavelet fractal interpolation is proposed after self-similarity analysis of wavefront distortion caused by atmospheric turbulence. Fast wavelet decomposition is operated to multiresolution analyze the wavefront phase spectrum, during which soft threshold denoising is carried out. The resolution of estimated wavefront phase is then improved by fractal interpolation. Finally, fast wavelet reconstruction is taken to recover wavefront phase. Simulation results reflect the superiority of our method in homodyne detection. Compared with minimum variance estimation (MVE) method based on interpolation techniques, the proposed method could obtain superior homodyne detection efficiency with lower operation complexity. Our research findings have theoretical significance in the design of coherent FSO communication system.

Aimed at analyzing the coherent receiving efficiency of a satellite-ground coherent laser communication system, polarization state of the received light is analyzed. We choose the circularly polarized, partially coherent laser as transmitted light source. The analysis process includes 3 parts. Firstly, an theoretical model to analyze received light's polarization state is constructed based on Gaussian-Schell model (GSM) and cross spectral density function matrix. Then, analytic formulas to calculate coherent receiving efficiency are derived in which both initial ellipticity modification and deflection angle between polarization axes of the received light and the intrinsic light are considered. At last, numerical simulations are operated based on our study. The research findings investigate variations of polarization state and obtain analytic formulas to calculate the coherent receiving efficiency. Our study has theoretical guiding significances in construction and optimization of satellite-ground coherent laser communication system.

Considering the weather’s influence to atmospheric transmittance, the paper modifies the attenuation matrix in the basement of original MIMO FSOC system channel model. And then, based on the modified channel model, the capacity in different given conditions is shown through numerical simulation. The paper simulates the capacity in different transmitting antenna’s height as well as in different weather. Considering that in most conditions, the optical signal doesn’t transfer vertically, the paper stimulates the capacity versus system slant angle. The paper also simulates difference value of capacity. At last, the paper designs a software to evaluate whether the given conditions are fit for communication or not.

The application of asymmetrically clipped optical-orthogonal frequency division multiplexing (ACO-OFDM) in free-space optical (FSO) communication system can increase the system channel capacity, while the use of channel estimation technology can ensure that ACO-OFDM has better performance. Since the channel estimation performance is directly affected by the selection of pilot patterns, especially when using compressed sensing (CS), it has been a major task in OFDM transmission schemes. In order to improve the channel reconstruction accuracy, a hybrid optimization algorithm based on genetic algorithm (GA) and particle swarm optimization (PSO) algorithm is proposed for two types of pilot design criterion. Simulation results show that compared with other three algorithms, the proposed algorithm has faster convergence speed and lower convergence value. With the pilots designed by the proposed algorithm, the system can achieve higher channel reconstruction accuracy.

Reception diversity laser communication can improve the channel capacity as well as weaken light intensity scintillation caused by atmospheric turbulence. However, it can’t reduce the wave front distortion. Wave front distortion is usually corrected by adaptive optics system, because that reception diversity laser communication has more than one receiver, it would take much more time as well as resources to correct the distortion of different receivers. Based on the analysis of wave front distortion of different receivers, we set the best correcting voltage of one receiver as the initial correcting voltage of the other receiver, it can be concluded from the simulation that using the method we propose need less iteration times than the traditional methods when achieving same correcting effect and it can also achieve higher correcting effect when setting same iteration times.

In this paper, the wavefront phase distortion of laser beam caused by atmospheric turbulence is corrected by an adaptive optics sensor-less system. According to the shortcoming that particle swarm optimization algorithm(PSO) is easily falling into local optimum, an improved PSO algorithm based on metropolis criterion is proposed in order to improve the efficiency and effect of wavefront correction. The metropolis criterion is used to judge whether an inferior state is accepted or not, so that the particle swarm optimization algorithm can jump out of the local optimum. Finally, the correcting effect of the improved PSO algorithm is compared by numerical simulation analysis, which verifies that the improved PSO algorithm can improve the correcting speed and effect, and the running time of achieving the same correcting effect is greatly reduced.

Interleaving scheme has found its applications in free space optical (FSO) communication system to cope with successive burst errors caused by atmospheric turbulence. However, the high data transfer rate of FSO communication requires high throughput interleaving, which poses unique challenges for the existing interleaver. In this paper, we present a novel interleaving scheme by using combinations of byte-wise interleaver and serializer/deserializer (SerDes) structure. A straightforward model is established to derive tight approximate expressions of post forward error correction (FEC) bit error rate (BER) over the atmospheric turbulence channel. Simulation results show that the proposed scheme has advantage of better BER performance in coping with successive burst errors over the existing interleaving schemes, and it also has a relatively high throughput capacity which is applicable to the FSO communication system.

Differential item/test functioning (DIF/DTF) are routine procedures to detect item/test unfairness as an explanation for group performance difference. However, unequal sample sizes and small sample sizes have an impact on the statistical power of the DIF/DTF detection procedures. Furthermore, DIF/DTF cannot be used for two test forms without common items. One of the advantages of person-fit analysis (PFA) is that even with small sample sizes, and/or no common items, PFA can still be utilized to investigate whether different subgroups are on the same scale. This study used simulation data and empirical data from a large-scale state high school assessment to demonstrate test fairness between nonaccommodated and accommodated forms. The results of this study showed that the accommodated form was comparable with the nonaccommodated form within the same construct, and PFA performs well for scale comparability purposes regardless of the size of the subgroups and number of common items.

An analytical formula model which is used to describe laser beam’s depolarization characteristics is solved based on multiple Rayleigh scattering model. Firstly, by using Stokes vector to characterize intensity and polarization, while at the same time using Mueller matrix and rotation matrix to characterize polarization changing in scattering procedure, a single scattering model is built. Then, a multiple scattering model is built considering the effects of atmospheric absorbing and scattering attenuation. The received light’s Stokes vectors through multiple scattering procedure are separately solved. At last, on the basis of multiple scattering vectors, the depolarization characteristics of laser beam propagation through atmosphere are estimated though calculating ratio of depolarization and polarized angle shifting. The numerical analysis based on analytical conclusion of this paper shows that for a horizontal polarized laser beam, its ratio of depolarization is about 1% and polarized angle shifting is about 0.3。 when propagates through atmosphere and arrives into the receiver on the ground, and both the above characteristics have only a small change compared with the change of cloud’s depth. The findings of these research show that Rayleigh scattering from atmosphere has a weak effect on the laser beam’s polarization status. The multiple scattering model and Stokes vector analytical formulas raised in the paper could also be used to study the depolarization characteristics of ellipse polarized laser beam and partially polarized laser beam propagating through atmosphere. The research findings of this paper will have theoretical guiding significances in the domain of laser communication, laser detection and laser imaging.

In satellite-to-ground laser communication, atmospheric turbulence will seriously deteriorate the system performance. The DPSK modulation technology is usually used to control the influence of atmospheric turbulence. The Meijer G-function is used to give the closed-form expression of the average bit error rate (ABER) of the system considering the combined influence of the atmospheric turbulence and the pointing errors, where the atmospheric turbulence channel is submitted to the Gamma-Gamma distribution and the pointing errors is submitted to the Beckman distribution. Through numerical simulation, the influence of system transmitting power, normalized beam width and zenith angle on the BER performance of the system is analyzed. The simulation results show that the ABER of the system decreases with the increase of the transmitting power, the error performance of the system considered the bias errors is obviously higher, and the error performance is also different when the azimuth and elevation normalized jitter deviation are not equal. The system performance will decline rapidly with the increase of the zenith angle. The BER of the system decrease firstly and then increase with the increase of the normalized beam width, and the optimal normalized beam width can be found to achieve the best performance.

The utilization of beam-carrying orbital angular momentum (OAM) for free-space optical (FSO) communication can increase channel capacity. However, the misalignment of the beam is an effect that must be mitigated in FSO communication systems. Due to the robustness of deep learning technology in pattern recognition, a neural network structure is proposed and improved to mitigate the effect of misalignment error. First, compared with the simple convolutional neural network proposed, data augmentation is adopted in the training. Then, a view-pooling layer is added after the convolutional layer. This layer can longitudinally compress feature maps from multiple receiving angles. In order to verify the performance of the proposed method, related experiments are reported in this paper. It can be seen from the results that when the tilt angle is less than 35°, the accuracy of OAM mode detection is above 99%, 93%, and 88%, respectively, corresponding to the condition of weak (Cn2=1×10−15 m−2/3), medium (Cn2=1×10−14 m−2/3) and strong (Cn2=1×10−13 m−2/3) turbulence.

Immigrant students are commonly assumed lower performers in US schools. Their inadequate English language skills and adaptation to the mainstream US school norms are often seen as obstacles to their successful school learning. However, whether and to what extent this assumption is sustainable for immigrant students' performances in mathematics is the question that has not been empirically explored. Proper answer to the question would help verify the popular assumption about the immigrant students and their learning in the mainstream US schools. Guided by the straight-line, segmented assimilation and cultural capital theories, this study examined this issue using US grades 4 and 8 datasets of Trend in International Mathematics and Science Study 2007 and 15-year-old dataset of Program for International Student Assessment 2009. It was found that there were substantial differences in the mathematics performances of students across different racial groups. Being immigrant students does not always mean they are lower performers than their mainstream peers. The immigrant students coming to the USA earlier did not always show worse mathematics performance over their immigrant peers who came to the USA later. These findings challenge the popular assumption that immigrant students' inadequate English language skills and adaptation to the mainstream US school norms are obstacles to their successful school learning and call for a deeper understanding about the academic performance of immigrant students in different content areas and at various stages of immigration across different racial groups.

This study, through multilevel analyses of the data of four English-speaking nations (i.e., Canada, England, New Zealand and the United States) from the Progress in International Reading Literacy Study (PIRLS) 2001 database, investigated the relationship between teachers' uses of various types of classroom assessments and their fourth-graders' reading literacy achievement, reading self-concept, and attitudes toward reading. The results showed varied outcomes associated with teachers' uses of different types of assessments (multiple-choice items, short-answer and paragraph writing, and oral communication) across countries and across aspects of student reading achievement. Implication of the study and recommendations for future research are discussed.

This article introduces two new classification consistency indices that can be used when item response theory (IRT) models have been applied. The new indices are shown to be related to Rudner’s classification accuracy index and Guo’s classification accuracy index. The Rudner- and Guo-based classification accuracy and consistency indices are evaluated and compared with estimates from the more commonly applied IRT-recursive procedure using a simulation study and data from two large-scale assessments. Results from the simulation study and practical examples suggested that the Guo- and Rudner-based indices tended to produce estimates that were closer to the simulated values and exceeded those from the IRT-recursive-based procedure. However, results did suggest that the Rudner- and Guo-based indices can have some undesirable features that are important to keep in mind when applying them in practice. The values of the classification accuracy and consistency indices appeared to be affected by a number of factors including the distribution of examinees, test length, the placement of the cut-scores, and the proficiency estimators applied to estimate examinee ability. Suggestions are made that an important part of investigations evaluating classification accuracy and consistency indices should be the creation of figures that show the value of the classification accuracy and classification consistency for individual examinees across the range of possible scores as these figures can help provide indications into subtle and important differences between indices.

Orthogonal frequency division multiplexing (OFDM) technique applied to the atmospheric optical communication can improve data transmission rate, restrain pulse interference, and reduce effect of multipath caused by atmospheric scattering. Channel estimation, as one of the important modules in OFDM, has been investigated thoroughly and widely with great progress. In atmospheric optical communication system, channel estimation methods based on pilot are common approaches, such as traditional least-squares (LS) algorithm and minimum mean square error (MMSE) algorithm. However, sensitivity of the noise effects and high complexity of computation are shortcomings of LS algorithm and MMSE algorithm, respectively. Here, a new method based on compressive sensing is proposed to estimate the channel state information of atmospheric optical communication OFDM system, especially when the condition is closely associated with turbulence. Firstly, time-varying channel model is established under the condition of turbulence. Then, in consideration of multipath effect, sparse channel model is available for compressive sensing. And, the pilot signal is reconstructed with orthogonal matching tracking (OMP) algorithm, which is used for reconstruction. By contrast, the work of channel estimation is completed by LS algorithm as well. After that, simulations are conducted respectively in two different indexes -signal error rate (SER) and mean square error (MSE). Finally, result shows that compared with LS algorithm, the application of compressive sensing can improve the performance of SER and MSE. Theoretical analysis and simulation results show that the proposed method is reasonable and efficient.

The field of literacy education has long been concerned with the question of how to help classroom teachers improve their practices so that students will improve as readers. Although there is consensus on what characterizes effective professional development, the reading research on which this consensus is based most often is small scale and involves direct support provided by university faculty. The South Carolina Reading Initiative is an exception: It is a statewide, site-based, large-scale staff development effort led by site-selected literacy coaches. Although university faculty provide long-term staff development to the coaches, the faculty are not directly involved with the professional development provided to teachers. In this study we sought to understand whether site-based, site-chosen literacy coaches could help teachers’ beliefs and practices become more consistent with what the field considers to be best practices. To understand teacher change, we used two surveys (Theoretical Orientation to Reading Profile, n = 817; South Carolina Reading Profile, n = 1,005) and case study research ( n = 39) to document teachers’ beliefs and practices. We also had access to a state department survey ( n = 1,428). Across these data, we found that teachers’ beliefs and practices became increasingly consistent with best practices as defined by standards set by the South Carolina State Department of Education, standards that were consistent with national standards. This suggests that large-scale staff development can affect teachers when the providers are site-based, site-selected literacy coaches.

We present the performance benefits of differential phase-shift keying (DPSK) modulation in eliminating influence from atmospheric turbulence, especially for coherent free space optical (FSO) communication with a high communication rate. Analytic expression of detected signal is derived, based on which, homodyne detection efficiency is calculated to indicate the performance of wavefront compensation. Considered laser pulses always suffer from atmospheric scattering effect by clouds, intersymbol interference (ISI) in high-speed FSO communication link is analyzed. Correspondingly, the channel equalization method of a binormalized modified constant modulus algorithm based on set-membership filtering (SM-BNMCMA) is proposed to solve the ISI problem. Finally, through the comparison with existing channel equalization methods, its performance benefits of both ISI elimination and convergence speed are verified. The research findings have theoretical significance in a high-speed FSO communication system.

The present study was designed to examine pre‐service teachers’ attitudes towards teacher self‐disclosure in Chinese and US classroom teaching. The participants of this study included 126 Chinese pre‐service teachers and 180 US pre‐service teachers. Results showed statistically significant differences between the two groups in their attitudes towards five dimensions of teacher self‐disclosure: common topics, uncommon topics, common purposes, uncommon purposes and consideration of students. The discussion focuses on the underlying reasons for the differences and the implications for cross‐cultural education.

In the scoring of performance assessments, when two raters assign different ratings some method must be used to resolve the discrepant ratings to form an operational score for reporting. This study investigated the differential impact of various resolution methods on the operational scores for gender and ethnic groups. The mean operational scores, and the passing rates for each group on two essay prompts were compared using three resolution methods (rater mean, tertium quid, and parity). The results indicated that for female and African American students, resolution typically resulted in greater reduction of mean operational ratings and passing rates than for those of their male or White counterparts. Differential item functioning (DIF) analyses were conducted using IRT-based logistic regression models. No apparent gender-related DIF was detected. Although uniform DIF was found for the ethnic groups, the effect was small, and there was not enough evidence to support the hypothesis that DIF could be associated with a resolution method.

Because of parameter sensitivity of chaotic systems, the minute variation of system parameters results in entirely different activation of system. Aimed to solve the problem resulted from the variation of parameters in the period of chaos synchronization, a adaptive synchronization controlling rule was presented and analyzed. According to the controlling rule an adaptive synchronization controller was designed. The theoretical analyses and simulations show that continuous-time chaotic systems with the unknown parameters and the different initial conditions can be quickly synchronized by the controlling rule. In addition, the parameters of driver system can be accurately identified by the controlling rule.