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Additional file 1: Figure S1. Overview of RNA-seq mapping in chicken genome. Figure S2. Gene coverage of different samples. Figure S3. Sample randomness distribution.

Anomalous behaviors such as the memory of the initial state, the ballistic diffusion, and the break of the equipartition theorem and the ergodicity in Brownian motions are investigated by solving analytically the generalized Langevin equation of non-relativistic Brownian particles with colored noise. These behaviors can also be observed in the Brownian motion of relativistic particles by solving numerically the generalized Langevin equation for specially chosen memory kernels. Our analyses give rise to think about the possible anomalous motion of heavy quarks in relativistic heavy-ion collisions., Comment: 13 pages, 12 figures

Additional file 2: Table S1. Data quality assessment in sequencing.

PurposeThis study aimed to evaluate the rates of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki67 heterogeneity in multifocal or multicentric breast cancer (MMBC) and its association with treatment pattern and disease outcomes.MethodsMMBC patients with ER, PR, HER2, and Ki67 results for each tumor focus were retrospectively analyzed using Kappa test and categorized into the homogeneous group (Homo group) and the heterogeneous group (Hetero group). Chi-square tests were performed to compare the clinical features and treatment options between the groups. Disease-free survival (DFS) and overall survival (OS) rates were estimated from Kaplan–Meier curves and compared between two groups.ResultsA total of 387 patients were included, and 93 (24.0%) were classified into the Hetero group. Adjuvant endocrine therapy was more frequently assigned for patients in the Hetero group than in the Homo group (84.9% vs. 71.7%, p = 0.046). There was no difference in terms of adjuvant anti-HER2 therapy (28.3% vs. 19.6%, p = 0.196) and chemotherapy (69.9% vs. 69.8%, p = 0.987) usage between the two groups. At a median follow-up of 36 months, DFS rates were 81.2% for the Hetero group and 96.5% for the Homo group (p = 0.041; adjusted HR, 2.95; 95% CI, 1.04–8.37). The estimated 3-year OS rates for the groups were 95.8% and 99.5%, respectively (p = 0.059; adjusted HR, 5.36; 95% CI, 0.97–29.69).ConclusionHeterogeneity of ER, PR, HER2, or Ki67 was present in 24.0% patients with MMBC. Biomarkers heterogeneity influenced adjuvant endocrine therapy usage and was associated with worse disease outcomes, indicating further clinical evaluation.

African swine fever (ASF) is a highly contact infectious disease caused by the African swine fever virus (ASFV). The extremely complex structure and infection mechanism make it difficult to control the spread of ASFV and develop the vaccine. The ASFV genome is huge with many antigenic genes. Among them, CP204L (p30), CP530R (pp62), E183L (p54), B646L (p72), and EP402R (CD2v) are involved in the process of the virus cycle, with strong immunogenicity and the ability to induce the body to produce neutralizing antibodies. In this study, the recombinant virus rBartha-K61-pASFV that expresses the above ASFV antigen genes was constructed by Red/ET recombineering technology using pseudorabies virus (PRV) vaccine strain Bartha-K61. Western blot analysis showed that the ASFV antigen gene was expressed and the recombinant virus showed good genetic stability and proliferation characteristics in 15 continuous generations on porcine kidney (PK15) cells. The results of immunoassay of piglets and mice showed that rBartha-K61-pASFV had good immunogenicity and could induce higher antibody levels in the body. Therefore, PRV was a promising viral vector for expressing the ASFV antigen gene, and all the experiments in this study laid a foundation for the further development of a new viral vector vaccine of ASFV.

Additional file 1: Supplementary Figure 1. The workflow of ML in this study is as follows. A dataset was built using baseline demographic characteristics (gender, age, marital status, education level), clinical questionnaires (HAMD-24, CTQ), and cognitive function (SST, IGT). For the missing data problem, averages filled two missing values in RT of "suicide" word, and no other features were missing. Then, the data were normalized to the range of 0-1 by calling the MinMaxScaler function from sklearn.preprocessing module in Python 3.7, so that different specification could be converted into an exact specification. Subsequently, the dataset was randomly divided into training and test sets in a ratio of 7:3 by calling the train_test_split function from sklearn.model_selection module. Because this is a small sample size study, and we wanted to observe the importance of all features in assessing the suicide risk of MDD patients, we did not perform feature selection to reduce the dimension. In the training phase of the ML models, the XGBoost-1 and XGBoost-2 were constructed with different feature sets but the same workflow. We selected hyper-parameters by grid search and 10-fold cross-validation using the Scikit-Learn library, and in this work, we set the n_estimators as a range of 1-200 and the max_depth as a range of 1-10. Then we used the independent test set to validate the performance of the models and got the final results. Supplementary Figure 2. The pre-selected feature sets of XGBoost 1 were evaluated through the Shapley values. Model 1 predicts whether the patients with MMD as suicide attempter mainly according to HAMD-24. Other characteristics affected the judgment of the model to varying degrees.

Supplemental material, sj-docx-1-tct-10.1177_15330338211045198 for Pure and Mixed Tubular Carcinoma of the Breast: Mammographic Features, Clinicopathological Characteristics and Prognostic Analysis by Chanjuan Wen, Weimin Xu, Genggeng Qin, Hui Zeng, Zilong He, Sina Wang, Zeyuan Xu, Mengwei Ma, Zhendong Luo and Weiguo Chen in Technology in Cancer Research & Treatment

Supplemental material, sj-docx-1-tct-10.1177_15330338211045198 for Pure and Mixed Tubular Carcinoma of the Breast: Mammographic Features, Clinicopathological Characteristics and Prognostic Analysis by Chanjuan Wen, Weimin Xu, Genggeng Qin, Hui Zeng, Zilong He, Sina Wang, Zeyuan Xu, Mengwei Ma, Zhendong Luo and Weiguo Chen in Technology in Cancer Research & Treatment

Inducing cell death while simultaneously enhancing antitumor immune responses is a promising therapeutic approach for multiple cancers. Celastrol (Cel) and 7-ethyl-10-hydroxycamptothecin (SN38) have contrasting physicochemical properties, but strong synergy in immunogenic cell death induction and anticancer activity. Herein, a hypoxia-sensitive nanosystem (CS@TAP) was designed to demonstrate effective immunotherapy for colorectal cancer by systemic delivery of an immunostimulatory chemotherapy combination. Furthermore, the combination of CS@TAP with anti-PD-L1 mAb (αPD-L1) exhibited a significant therapeutic benefit of delaying tumor growth and increased local doses of immunogenic signaling and T-cell infiltration, ultimately extending survival. We conclude that CS@TAP is an effective inducer of immunogenic cell death (ICD) in cancer immunotherapy. Therefore, this study provides an encouraging strategy to synergistically induce immunogenic cell death to enhance tumor cytotoxic T lymphocytes (CTLs) infiltration for anticancer immunotherapy.

Sanghuangporus vaninii, also called ‘Sanghuang’ mushroom in Chinese, has various medicinal uses, but its effects on human melanoma cells have not been reported. The present study investigated the inhibitory ability and potential anticancer mechanism of the aqueous extracts of S. vaninii (SH). The results revealed that SH inhibited the proliferation of A375 human melanoma cells in a dose-dependent manner, and flow cytometry analysis suggested that SH induced A375 cell cycle arrest at S phase and apoptosis. Reverse transcription-quantitative PCR, western blotting and immunofluorescence analyses indicated that SH induced S-phase arrest by upregulating p21 expression, and p21 inhibited the expression of cyclin-cyclin-dependent kinases complexes at both the RNA and protein levels. In addition, SH induced apoptosis of A375 cells by inhibiting the expression levels of the anti-apoptosis gene Bcl-2. Therefore, the results suggested that SH may be a potential candidate for the treatment of human melanoma, thus providing new ideas for developing drugs that target melanoma.

In the absence of pre-processing, polyethylene terephthalate (PET) non-woven have strong hydrophobicity. Therefore, patterns printed with pigment ink-jet printing have poor color yield and low reso...

Exogenously administered B-type natriuretic peptide (BNP) has been shown to provide cardioprotection against various heart diseases. However, the underlying mechanisms remain elusive. This study explores whether BNP exerts its cardioprotection against hypoxia/reoxygenation (H/R) injury under high glucose/high fat (HG/HF) conditions in cardiac H9c2 cells and uncovers the underlying mechanisms. Our data revealed that BNP significantly increased the cell viability and decreased the release of lactate dehydrogenase (LDH) and creatine kinase (CK), with a maximal effect at the BNP concentration of 10−7 mol/L. In addition, by analyzing the activation of cleaved caspase-3 and by Annexin V-FITC/PI staining, we showed that BNP attenuated H/R-induced cell apoptosis in HG/HF conditions. Western blot analysis showed enhanced phosphorylation of protein kinase RNA (PKR)-like endoplastmic reticulum (ER) kinase (PERK) and eukaryotic initiation factor 2α (eIF2α)(one of the three main signaling pathways in endoplastmic reticulum (ER) stress), and increased expression of GRP78 and CHOP proteins (ER stress-related proteins) in H9c2 cells which underwent H/R in HG/HF conditions. Treatment with BNP or 8-Br-cGMP (an analog of cGMP) reversed this activation. However, this effect was significantly weakened by KT-5823, a selective cGMP-dependent protein kinase G (PKG) inhibitor. In addition, similar to BNP, treatment with a specific inhibitor of ER stress tauroursodeoxycholic acid (TUDCA) protected the cells against H/R injury exposed to HG/HF conditions. In conclusion, these findings demonstrated that BNP effectively protected cells against H/R injury under HG/HF conditions by inhibiting the ER stress via activation of the cGMP-PKG signaling pathway.

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As the consumption level of my country's residents increases, customers' requirements for the quality of aviation services are also increasing. Airlines must constantly improve service quality to be satisfied with the increasing demands of customers. The application of big data technology is conducive to improving the quality of aviation services and improving customer satisfaction in the air transportation industry. The relation between aviation quality of service and customer satisfaction is studied in this article. At the same time, how big data technology should be used to improve aviation service quality and improve customer satisfaction is discussed in this article.

It is well-known that polypropylene (PP) or aramid fibers are challenging to dye by using conventional dyeing methods, which limits their further development in the textile and garment industry. Herein, we report a new methodology for deep dyeing synthetic fibers employing synthesized diazirine-containing dyestuffs. The combination of the diazirine moiety with a chromophore with heating at 150 °C produced the dye-forming carbene intermediate, which could covalently bond with the C–H bonds in the synthetic fibers. It was demonstrated that the diazirine dyes did not pose any explosive risk, although nitrogen molecules were generated along with the formation of carbene. Compared with the high-temperature–high-pressure dyeing and carrier dyeing-fixation methods, the non-aqueous solvent dyeing–fixation method was screened and certified to be suitable for the reactive dyeing of synthetic fibers. The diazirine-based dyes could efficiently react with poly (ethyleneterephthalate), nylon, PP, aramid, acrylic, and polyurethane (spandex) fibers with moderate to excellent fixation values. Particularly, the color yields of the PP, aramid, and acrylic fabrics were further improved significantly by repeating the non-aqueous solvent dyeing–fixation operation. Thereafter, the detailed dyeing and fixing mechanisms of the reactive dyeing method were proposed. Finally, the color fastness properties of these dyed fabrics were demonstrated to be excellent, thus making such a reactive dyeing method for synthetic fibers a very promising one for the future.

The three genetic populations used in this study included a doubled-haploid (DH) population derived from ‘Hanxuan 10’ × ‘Lumai 14’, a BC3F6 population from ‘Lumai 14’ × ‘Jing 411’ [introgression line (IL) population 1], and a BC3F6 population from ‘Lumai 14’ × ‘Shaanhan 8675’ (IL population 2). The genetic characters underpinning kernel morphological traits, such as kernel length, kernel width, kernel thickness, kernel length/width ratio, kernel length/thickness ratio, and kernel width/thickness ratio were analyzed. Quantitative trait loci (QTL) for all the above traits were mapped in the three populations across six, three, and three environments, respectively. The genetic effects of qKW-6A, which was detected in all three populations, were analyzed. Forty six additive QTLs for kernel morphological traits were detected in the DH population, and 20 additive QTLs were detected in each of the IL populations. A kernel-width QTL, qKW-6A, was located within the same interval in all three populations. qKT-7A-3, qLTR-4A, and qWTR-7A-1 mapped in the DH population were located in the same marker intervals as qKT-7A-1, qLTR-4A, and qWTR-7A-1, respectively, in IL population 2. qLWR-5A-2, qWTR-5A-2, and qWTR-5A-1 from the DH population were detected in five, four, and three environments, and explained 14.72, 25.11, and 25.91%, respectively, of the phenotypic variation. qLTR-7A from IL population 1 and qLWR-5B from IL population 2, detected in all three environments, explained 6.10 and 10.66% of the phenotypic variation, respectively. On the other hand, negative alleles of qKW-6A for kernel width detected in all three populations were derived from ‘Lumai 14’. Donor segments including this QTL were introgressed into 18 lines of IL population 1 and 44 lines of IL population 2. The mean kernel width in these lines was greater than the recurrent parent ‘Lumai 14’ under drought-stress conditions in 2 years, indicating that qKW-6A played an important role in determination of kernel width. Line 157 from IL population 2 contained only five chromosomal segments from the donor parent, and these donor segments harbored no QTL for kernel width other than qKW-6A. However, kernel width in this line was significantly greater than that of ‘Lumai 14’ in all three environments. Thus, Line 157 can be regarded as a near-isogenic line for fine mapping and map-based cloning of qKW-6A.

Isoprenaline-induced cardiac hypertrophy can deteriorate to heart failure, which is a leading cause of mortality. Endogenous vasonatrin peptide (VNP) has been reported to be cardioprotective against myocardial ischemia/reperfusion injury in diabetic rats. However, little is known about the effect of exogenous VNP on cardiac hypertrophy. We further explored whether VNP attenuated isoprenaline-induced cardiomyocyte hypertrophy by examining the levels and activities of cGMP and PKG. In this study, we found that VNP significantly attenuated isoprenaline-induced myocardial hypertrophy and cardiac fibroblast activation in vivo. Moreover, VNP effectively halted the activation of apoptosis and oxidative stress in the isoprenaline-treated myocardium. VNP promoted superoxide dismutase (SOD) activity. Further study revealed that the protective effects of VNP might be mediated by the activity of the cGMP-PKG signaling pathway in vivo or in vitro, while the use of agonists and antagonists confirmed these results. Therefore, we demonstrated that the antiapoptosis and antioxidative stress effects of VNP depends on elevated cGMP-PKG signaling activity both in vivo and in vitro. These results suggest that VNP may be used in the treatment of myocardial hypertrophy.

Background and Objective In recent years, an increasing number of clinical prediction models have been developed to serve clinical care. Establishing a data-driven prediction model based on large-scale electronic health record (EHR) data can provide a more empirical basis for clinical decision making. However, research on model generalization and continuous improvement is insufficiently focused, which also hinders the application and evaluation of prediction models in real clinical environments. Therefore, this study proposes a multicenter collaborative prediction model construction framework to build a prediction model with greater generalizability and continuous improvement capabilities while preserving patient data security and privacy. Materials and Methods Based on a multicenter collaborative research network, such as the Observational Health Data Sciences and Informatics (OHDSI), a multicenter collaborative prediction model construction framework is proposed. Based on the idea of multi-source transfer learning, in each source hospital, a base classifier was trained according to the model research setting. Then, in the target hospital with missing calibration data, a prediction model was established through weighted integration of base classifiers from source hospitals based on the smoothness assumption. Moreover, a passive-aggressive online learning algorithm was used for continuous improvement of the prediction model, which can help to maintain a high predictive performance to provide reliable clinical decision-making abilities. To evaluate the proposed prediction model construction framework, a prototype system for colorectal cancer prognosis prediction was developed. To evaluate the performance of models, 70,906 patients were screened, including 70,090 from 5 US hospital-specific datasets and 816 from a Chinese hospital-specific dataset. The area under the receiver operating characteristic curve (AUC) and the estimated calibration index (ECI) were used to evaluate the discrimination and calibration of models. Results Regarding the colorectal cancer prognosis prediction in our prototype system, compared with the reference models, our model achieved a better performance in model calibration (ECI = 9.294 [9.146, 9.441]) and a similar ability in model discrimination (AUC = 0.783 [0.780, 0.786]). Furthermore, the online learning process provided in this study can continuously improve the performance of the prediction model when patient data with specified labels arrive (the AUC value increased from 0.709 to 0.715 and the ECI value decreased from 13.013 to 9.634 after 650 patient instances with specified labels from the Chinese hospital arrived), enabling the prediction model to maintain a good predictive performance during clinical application. Conclusions This study proposes and evaluates a multicenter collaborative prediction model construction framework that can support the construction of prediction models with better generalizability and continuous improvement capabilities without the need to aggregate multicenter patient-level data.

A series of new azo disperse dyes containing the urethane group were synthesized through the reaction between the hydroxyl group in coupling component of disperse dyes and p-toluene isocyanate. The structures of the new dyes were fully confirmed by 1H NMR, 13C NMR, FT-IR, MS and Elemental analysis. Their characteristics for the visible-light absorption and color fastness on polyamide fibers were respectively measured and compared with those of the original dye. It was found that the new dyes exhibited hypsochromic effect, and had the nearly unchanged absorption half band and higher molar extinction coefficients, the fastness properties has been greatly improved, especially for the washing and sublimation fastness. The new dyes 2d and 2e containing double urethane groups possessed excellent fastness properties on polyamide fabrics. These two dyes for all the fastness tested, including water fastness, sublimation fastness, rubbing fastness and light fastness, had reached 4–5 and 5 rates. It was very clear that the introduction of urethane group and the increase of molecular weight can effectively improve the fastness of disperse dyes for the polyamide fibers.

The photoyellowing progress of silk fibroin and its influence factors under ultraviolet irradiation have been studied, which was conducted by combining different ultraviolet wavelengths, different ultraviolet irradiancies, and different irradiation times. The blue-ray whiteness after ultraviolet irradiation was tested to characterize the course of photoyellowing of silk fibroin. The result shows that the photoyellowing degree of silk fibroin varies significantly under ultraviolet irradiation of different wavelengths and with the increasing in ultraviolet irradiancy at 313-nm wavelength, the photoyellowing degree aggravates correspondingly, while the ultraviolet irradiancy at 340-nm wavelength has little obvious impact. Additionally, the photoyellowing degree of silk fibroin is positively correlated to ultraviolet irradiancy and irradiation time. To quantitatively analyze the alteration of tyrosine content during the photoyellowing of the silk fibroin, l-tyrosine standard curve Y = 8.14666X − 0.88951 was e...

SUMMARYDelayed senescence, or stay-green, contributes to a longer grain-filling period and has been regarded as a desirable characteristic for the production of a number of crops including wheat. In the present study, in order to identify quantitative trait loci (QTLs) for traits related to the progression of wheat flag leaf senescence, green leaf area duration (GLAD) of a doubled haploid (DH) population, derived from two winter wheat varieties Hanxuan10 and Lumai14, was visually estimated under two water conditions and was recorded at 3-day intervals from 10 days after anthesis to physiological maturity using a 0–9 scale. According to GLAD, parameters related to the progression of senescence of DH lines and their parents were estimated by the Gompertz statistical model. Based on the model parameters, DH lines were categorized into three groups under drought stress and four groups under well-watered conditions. A total of 24 additive QTLs and 23 pairs of epistatic QTLs for parameters related to the progression of senescence were identified on 18 chromosomes, except for 3B, 1D and 6D. Of the QTLs detected, 14 and 10 additive QTLs were associated with the investigated traits under drought stress and well-watered conditions, respectively. Furthermore, 4, 7, 6, 2 and 2 additive QTLs for traits related to progression of senescence were clustered around the same or similar regions of chromosomes 1A, 1B, 5A, 5B and 7A, respectively. The present data provided the genetic basis for high phenotypic correlations among traits related to the progression of wheat flag leaf senescence. In addition, 17 loci were co-located or linked with previously reported QTLs regulating chlorophyll fluorescence, high-light-induced photo-oxidation, or heat stress and dark-induced senescence. The markerXwmc336on chromosome 1A, responsible for the onset and end times of leaf senescence, the time to maximum rate of senescence, the time to reach 75% senescence and chlorophyll content under drought stress may be helpful for marker-assisted selection breeding of wheat.

This paper describes how coloration of silk can be achieved using a coupling reaction between a diazonium compound, made from Color Base Red G (C.I. 37105) and tyrosine residues in the silk protein fibroin. A pigment with an azo structure obtained from the reaction between the diazonium of Color Base Red G with p-methylphenol was synthesized and studied as a model compound for the coloration reaction. The colored materials were characterized using UV-vis, FT-Raman, FT-IR, 1H-NMR, and mass spectroscopy. Both the colored silk and the model compound gave yellow colors with absorption maxima in the region of 400 nm. The results suggest that the use of coupling reactions could be developed into a dyeing method for protein fibers or other protein materials that contain tyrosine residues. Because the chromophores are incorporated into the protein chains, such dyed silks should have good wet fastness properties.

Silk fibrillation, one major weakness of silk fibers, can lead to undesirable fabric appearance. In this research, an effective method for reducing the fibrillation of silk fibers through the graft copolymerization with methyl methacrylate (MMA) has been developed. The major copolymerization factors such as the initiator concentration, MMA monomer concentration, reaction time and temperature were investigated. An AATCC Crockmeter was used to rub the fabric to simulate the abrasion in production to generate the fibrillation. The microscope observation and the evaluation of fibrillation index (FI) were applied to assess the degree of fibrillation of silk fibers. The optimum graft copolymerization factors were obtained. Instrumental analyses, such as FTIR, TG and SEM, proved that the silk fabric had been successfully grafted with MMA monomers. The fibrillation of the grafted silk fibers was considerably reduced since the coated PMMA can protect the silk fiber. In addition, the physical properties such as the crease recovery, breaking strength, and the breaking length of the grafted silk fabrics were also improved.

Rate control is an integral part of high-fidelity video coding. Since the first call for proposal, many rate control algorithms have been incorporated into the HEVC standard to prepare for its practical use in the future. The state of the art SATD based intra frame rate control strategy (SATDRC) achieves stable controlling performance. However, the average bit mismatch on the frame level (BMF) reaches 0.62%, with the highest 1.47%, which may lead to unsteady video services in bandwidth constrained applications. In this paper, an adaptive frame level bit mismatch rectification scheme (AFBMR) is proposed for SATDRC to reduce the gap between allocated bits and generated bits. BMF is utilized to adjust bits allocated to a frame adaptively in accordance with sequence characteristics. Experimental results show that the proposed method reduces bit inconsistency by 37.33% on average, enhancing bit rate accuracy as well as providing steadier bit streams without introducing extra computational complexity and loss of video quality.

Foreign and domestic research status of military equipment software supportability is analyzed. Quantitative research and qualitative research is adopted as the measurement principle to depart the research into two parts. The research status is studied from supportability process modelling, model analysis, qualitative comparison and parameters quantitative methods. The comprehensive analysis process of software supportability assessment is researched. The existing problems of current research status are analyzed and the upcoming research direction is put forward.

Abstract In this work, the corrosion behavior and mechanical degradation of two types of pipe steel, Inconoy 825 and L360, after two years of high sour environments service in Puguang gas-field were studied. Results demonstrated that a fearful elemental sulfur layer deposited on the inner wall of pipeline, pitting corrosion and hydrogen-induced cracking was observed in L360 pipe. In comparison, no pitting corrosion and hydrogen-induced cracking was found in Inconoy 825 steel pipe due to its excellent resistance to corrosion. Furthermore, mechanical properties (yield strength, impact strength, elongation, hardness, fracture toughness) and stress corrosion cracking were investigated. Results showed that the yield strength decreased obviously and the percentage of elongation increased in Inconoy 825 steel but little change in L360. The analysis a change of the mentioned mechanical characteristics together with the results of the diffusion and tapping of hydrogen of them indicated that the properties degradation of Inconoy 825 pipeline steel after long term service was associated with essential role of hydrogen in these processes. The consequences of sudden failures and severe corrosion of metallic material in the high sour gas-field, which associated with their exposure to H2S/CO2 containing gas, led to the preparation of evaluation tests of pipeline. However, passing evaluation tests cannot guarantee the safety in actual work condition unless the field experience had been at least two years. As the first attempt to exploit high sour gas-field in China, it is anticipated that this work of Puguang provides valuable data and an essential insight into the corrosion and degradation of pipeline steel services in high-sour environmental.

This paper uses extension classified prediction to predict monthly average humidity of cities. Using the concepts of matter-element and dependent function to establish prediction model, the prediction results can be obtained by means of cluster analysis. Through analyzing and calculating the historical data of Guangzhou City, the result shows that the extension cluster model in the prediction of humidity is valid.

We propose a novel structure of single-polarization single-mode(SPSM) holey fiber designed based on resonant coupling effect. The proposed fiber is able to achieve SPSM operation over an ultra-broad bandwidth as large as 920nm ranging from 1.48μm to 2.4μm, within which only one polarization state of the fundamental mode can be effectively guided. With the aid of six smaller holes around the central core, the effective mode area of the fiber is enlarged and the chromatic dispersion curve is flattened. The numerical results indicate that the proposed fiber achieves nearly zero ultra-flattened dispersion over a wide spectral range and the effective mode area is approaching ∼78μm 2 at 1550nm. Moreover, the structure shows superiority in output beam quality owing to the symmetry of the central core region, and also exhibits great modal compatibility with SMF.

Full-vector effective index method for modeling photonic crystal fiber is developed and the influence of structure parameters such as hole size, pitch and number removed in the center on endlessly single-mode and large mode area are discussed in the detail.

In this paper, a novel broadband polarization-insensitive dual-core photonic crystal fiber with elliptical central hole is proposed and the influence of its structural parameters on coupling characteristic is investigated in detail by the full-vector finite element method. Through optimizing the fiber structural parameters, broadband and polarization-insensitive characteristics are achieved over the whole optical communication band from 1.225 m to 1.675 m. The variation of coupling ratio is stabilized at 50% 1%, and the coupling ratio difference between x polarization and y polarization is less than 0.5% overall the wavelength range. Due to its relatively independent of cores and elliptical central hole and suitable structural parameters, this fiber meets the application requirements, that is, easy to fabricate, easy to splice and low splice loss. This research is freed from the current coupler limit: narrow bandwidth, wavelength dependence, polarization-sensitive, difficulty of fabricating, thereby provides the theoretical basis for the study of the large capacity high speed all-optical networks and multi-wavelength tunable fiber laser.

The flexible structure of photonic crystal fibre not only offers novel optical properties but also brings some difficulties in keeping the fibre structure in the fabrication process which inevitably cause the optical properties of the resulting fibre to deviate from the designed properties. Therefore, a method of evaluating the optical properties of the actual fibre is necessary for the purpose of application. Up to now, the methods employed to measure the properties of the actual photonic crystal fibre often require long fibre samples or complex expensive equipments. To our knowledge, there are few studies of modeling an actual photonic crystal fibre and evaluating its properties rapidly. In this paper, a novel method, based on the combination model of digital image processing and the finite element method, is proposed to rapidly model the optical properties of the actual photonic crystal fibre. Two kinds of photonic crystal fibres made by Crystal Fiber A/S are modeled. It is confirmed from numerical results that the proposed method is simple, rapid and accurate for evaluating the optical properties of the actual photonic crystal fibre without requiring complex equipment.