Evaluation of disease severity and prediction of severe cases in children hospitalized with influenza A (H1N1) infection during the post-COVID-19 era: a multicenter retrospective study.

BACKGROUND: The rebound of influenza A (H1N1) infection in post-COVID-19 era recently attracted enormous attention due the rapidly increased number of pediatric hospitalizations and the changed characteristics compared to classical H1N1 infection in pre-COVID-19 era. This study aimed to evaluate the clinical characteristics and severity of children hospitalized with H1N1 infection during post-COVID-19 period, and to construct a novel prediction model for severe H1N1 infection. METHODS: A total of 757 pediatric H1N1 inpatients from nine tertiary public hospitals in Yunnan and Shanghai, China, were retrospectively included, of which 431 patients diagnosed between February 2023 and July 2023 were divided into post-COVID-19 group, while the remaining 326 patients diagnosed between November 2018 and April 2019 were divided into pre-COVID-19 group. A 1:1 propensity-score matching (PSM) was adopted to balance demographic differences between pre- and post-COVID-19 groups, and then compared the severity across these two groups based on clinical and laboratory indicators. Additionally, a subgroup analysis in the original post-COVID-19 group (without PSM) was performed to investigate the independent risk factors for severe H1N1 infection in post-COIVD-19 era. Specifically, Least Absolute Shrinkage and Selection Operator (LASSO) regression was applied to select candidate predictors, and logistic regression was used to further identify independent risk factors, thus establishing a prediction model. Receiver operating characteristic (ROC) curve and calibration curve were utilized to assess discriminative capability and accuracy of the model, while decision curve analysis (DCA) was used to determine the clinical usefulness of the model. RESULTS: After PSM, the post-COVID-19 group showed longer fever duration, higher fever peak, more frequent cough and seizures, as well as higher levels of C-reactive protein (CRP), interleukin 6 (IL-6), IL-10, creatine kinase-MB (CK-MB) and fibrinogen, higher mechanical ventilation rate, longer length of hospital stay (LOS), as well as higher proportion of severe H1N1 infection (all P < 0.05), compared to the pre-COVID-19 group. Moreover, age, BMI, fever duration, leucocyte count, lymphocyte proportion, proportion of CD3+ T cells, tumor necrosis factor α (TNF-α), and IL-10 were confirmed to be independently associated with severe H1N1 infection in post-COVID-19 era. A prediction model integrating these above eight variables was established, and this model had good discrimination, accuracy, and clinical practicability. CONCLUSIONS: Pediatric H1N1 infection during post-COVID-19 era showed a higher overall disease severity than the classical H1N1 infection in pre-COVID-19 period. Meanwhile, cough and seizures were more prominent in children with H1N1 infection during post-COVID-19 era. Clinicians should be aware of these changes in such patients in clinical work. Furthermore, a simple and practical prediction model was constructed and internally validated here, which showed a good performance for predicting severe H1N1 infection in post-COVID-19 era.

Comparative study of first-principles approaches for effective Coulomb interaction strength Ueff between localized f-electrons: Lanthanide metals as an example.

As correlation strength has a key influence on the simulation of strongly correlated materials, many approaches have been proposed to obtain the parameter using first-principles calculations. However, a comparison of the different Coulomb strengths obtained using these approaches and an investigation of the mechanisms behind them are still needed. Taking lanthanide metals as an example, we research the factors that affect the effective Coulomb interaction strength, Ueff, by local screened Coulomb correction (LSCC), linear response (LR), and constrained random-phase approximation (cRPA) in the Vienna Ab initio Simulation Package. The Ueff LSCC value increases from 4.75 to 7.78 eV, Ueff LR is almost stable at about 6.0 eV (except for Eu, Er, and Yb), and Ueff cRPA shows a two-stage decreasing trend in both light and heavy lanthanides. To investigate these differences, we establish a scheme to analyze the coexistence and competition between the orbital localization and the screening effect. We find that LSCC and cRPA are dominated by the orbital localization and the screening effect, respectively, whereas LR shows the balance of the competition between the two factors. Additionally, the performance of these approaches is influenced by different starting points from the Perdew-Burke-Ernzerhof (PBE) and PBE + U, especially for cRPA. Our results provide useful knowledge for understanding the Ueff of lanthanide materials, and similar analyses can also be used in the research of other correlation strength simulation approaches.

[High-value utilization technology and approach of Chinese medicinal residues under background of "Dual Carbon"].

In recent years, the traditional Chinese medicine(TCM)industry has experienced rapid development, resulting in a significant amount of Chinese medicinal residues generated during the industrial manufacturing process. Currently, the main methods of handling Chinese medicinal residues include stacking, landfilling, and incineration, which lead to substantial resource waste and potential environmental pollution. With "carbon peak" and "carbon neutrality"( "Dual Carbon")becoming national strategic goals, the TCM industry is ushering in a new wave of "low-carbon" trends, and the high-value utilization of Chinese medicinal residues has become a breakthrough for implementing a low-carbon economy in the TCM sector. From the perspective of a low-carbon economy, this article reviewed literature in China and abroad to summarize the microbial transformation technology, enzymatic conversion technology, biomass pyrolysis, gasification, hydrothermal liquefaction, and other high-value utilization technologies for Chinese medicinal residues. It also overviewed the applications of Chinese medicinal residue in feed additives, organic fertilizers, edible mushroom cultivation substrates, preparation of activated carbon for wastewater treatment, and new energy batteries. Considering the current status of resource utilization of Chinese medicinal residues, feasible strategies and suggestions for resource development and utilization were proposed to improve the quality and efficiency of the Chinese medicinal resource industry chain and promote green development, thereby providing research ideas and theoretical basis for achieving carbon peak and carbon neutrality goals.

[Measures for waste and by-product recycling and circular economy of whole industry chain of traditional Chinese medicine resources facing carbon peak and carbon neutrality (dual carbon) goals].

It has become a common consensus that resource conservation and intensive recycling for improving resource utilization efficiency is an important way to achieve carbon peak and carbon neutrality(dual carbon). Traditonal Chinese medicine(TCM)resources as national strategic resources are the material basis and fundamental guarantee for the development of TCM industry and health services. However, the rapid growth of China's TCM industry and the continuous expansion and extension of the industrial chain have exposed the low efficiency of TCM resources. Resource waste and environmental pollution caused by the treatment and discharge of TCM waste have emerged as major problems faced by the development of the industry, which has aroused wide concern. Considering the dual carbon goals, this paper expounds the role and potential of TCM resource recycling and circular economy industry development. Taking the typical model of TCM resource recycling as the case of circular economy industry in reducing carbon source and increasing carbon sink, this paper puts forward the suggestions for the TCM circular economy industry serving the double carbon goals. The suggestions mainly include strengthening the policy and strategic leading role of the double carbon goals, building an objective evaluation system of low-carbon emission reduction in the whole industrial chain of TCM resources, building an industrial demonstration park for the recycling of TCM resources, and promoting the establishment of a circular economy system of the whole industrial chain of TCM resources. These measures are expected to guide the green transformation of TCM resource industry from linear economic model to circular economy model, provide support for improving the utilization efficiency and sustainable development of TCM resources, and facilitate the low-carbon and efficient development of TCM resource industry and the achievement of the double carbon goals.

[Recent research on the application of defoamers in children undergoing digestive endoscopy]. / ç¥›æ³¡å‰‚åœ¨å„¿ç«¥æ¶ˆåŒ–å† é•œä¸­çš„åº”ç”¨è¿›å±•.

Endoscopy is a common tool for the diagnosis and treatment of gastrointestinal disorders in children. The presence of bubbles in the gastrointestinal tract is one of the important factors affecting the clarity of endoscopic visual field, and the application of defoamers can significantly reduce bubbles in the gastrointestinal tract, improve the quality of gastrointestinal preparation, and further increase disease detection rate. Various studies have been conducted on gastrointestinal preparation before endoscopy in children, but there still lacks a uniform protocol for the application of defoamers. This article summarizes the use of defoamers in children before digestive endoscopy and related research advances and points out that existing studies on defoamers have a small sample size and that there are still controversies over the selection and timing of administration, so as to provide a reference for in-depth research on defoamers in the future.

Imaging Features Derived From Dynamic Contrast-Enhanced Magnetic Resonance Imaging to Differentiate Malignant From Benign Breast Lesions: A Systematic Review and Meta-Analysis.

MATERIALS AND METHODS: The PubMed, Web of Science, Embase, and the Cochrane Library databases were searched up to January 2021 to identify original studies that investigated the accuracy of individual DCE-MRI features in differentiating malignant from benign breast lesions. Pooled sensitivity, specificity, and area under the curve were calculated by STATA software based on the data extracted from included studies. Moreover, quality assessment, subgroup analysis, and publication bias evaluation were performed. RESULTS: Twenty-nine studies comprising 2976 patients and 3365 suspicious breast lesions were included. Malignant breast lesions tended to present irregular shapes (83.59%), noncircumscribed margins (85.50%), mass enhancement (52.31%), heterogeneous internal enhancement (71.72%), and type II or III time intensity curve (TIC) patterns (91.17%), showing significant differences compared with benign breast lesions (P < 0.05). For differentiating malignant from benign breast lesions, the area under the curve values of irregular shape, noncircumscribed margin, mass enhancement, heterogeneous internal enhancement, and type II or III TIC patterns were 0.79 (0.76-0.83), 0.87 (0.84-0.90), 0.63 (0.58-0.67), 0.82 (0.78-0.85), and 0.89 (0.86-0.92), respectively. CONCLUSIONS: Imaging features derived from DCE-MRI, especially TIC patterns, are important for diagnosing and differentiating malignant from benign breast lesions.

Whole-Liver Apparent Diffusion Coefficient Histogram Analysis for the Diagnosis and Staging of Liver Fibrosis.

BACKGROUND: Conventional diffusion-weighted imaging is limited in the quantitative evaluation of liver fibrosis, and whole-liver apparent diffusion coefficient (ADC) histogram analysis might contribute to the diagnosis and staging of liver fibrosis. PURPOSE: To explore the value of whole-liver ADC histogram parameters in the diagnosis and staging of liver fibrosis. STUDY TYPE: Retrospective. POPULATION: Twenty individuals with no liver disease and 86 patients with liver fibrosis, including 30 with chronic viral hepatitis, 29 with autoimmune hepatitis, and 27 with unexplained liver fibrosis patients. FIELD STRENGTH/SEQUENCE: 3.0T/T1 -weighted, T2 -weighted, and diffusion-weighted images. ASSESSMENT: A region of interest (ROI) was drawn in each slice of the diffusion-weighted images. Whole-liver histogram parameters were obtained with dedicated software by accumulating all ROIs. The effectiveness of the parameters in differentiating stage 1 or greater (≥F1), stage 2 or greater (≥F2), and stage 3 or greater (≥F3) liver fibrosis was assessed. STATISTICAL TESTS: Mann-Whitney U-test and receiver operating characteristic curve analysis. RESULTS: Kurtosis, entropy, skewness, mode, and 90th and 75th percentiles exhibited significant differences among the pathological fibrosis stages (P < 0.05). Kurtosis was found to be the most meaningful parameter in differentiating fibrosis stages of the viral hepatitis, autoimmune hepatitis, and unexplained liver fibrosis group (area under the curve) (AUC = 0.793, 0.771, 0.798, respectively). In the combined liver fibrosis group, kurtosis achieved the highest AUC (0.801; 95% confidence interval [CI]: 0.702-0.900; sensitivity: 0.750; specificity: 0.850; positive likelihood ratio: 4.953; negative likelihood ratio: 0.302; positive predictive value: 0.946; negative predictive value: 0.486), with a cutoff value of 1.817, in differentiating fibrosis stage ≥F1. DATA CONCLUSION: Kurtosis, entropy, skewness, mode, and 90th and 75th percentiles may contribute to the diagnosis and staging of liver fibrosis, especially kurtosis. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:1745-1754.

Diagnostic Efficacy of Contrast-Enhanced MRI in Detecting Residual or Recurrent Hepatocellular Carcinoma After Transarterial Chemoembolization: A Systematic Review and Meta-analysis.

BACKGROUND: The diagnostic efficacy of contrast-enhanced magnetic resonance imaging (CEMRI) in diagnosing residual or recurrent hepatocellular carcinoma (HCC) after transarterial chemoembolization (TACE) is currently not completely clear. PURPOSE: To investigate the diagnostic efficacy of CEMRI in detecting residual or recurrent HCCs after TACE by meta-analysis. STUDY TYPE: Systematic review and meta-analysis. POPULATION: A systematic literature search was performed in PubMed, Embase, Web of Science, Ovid, and the Cochrane Library database up to June 2019 to find original studies on diagnosing patients suspected of residual or recurrent HCCs after TACE with CEMRI. Thirteen studies comprising 721 nodules were finally included. FIELD STRENGTH/SEQUENCE: 1.5T or 3.0T, CEMRI. ASSESSMENT: Quality assessment of the included studies was performed by applying the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. STATISTICAL TESTS: Sensitivity and specificity were pooled with a bivariate random-effects model. Heterogeneity was assessed by the chi-square test. The potential sources of heterogeneity were explored by subgroup and publication bias analyses. RESULTS: The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic (ROC) curve (AUC) of CEMRI in diagnosing residual or recurrent HCCs after TACE were 91% (95% confidence interval [CI]: 87%-96%), 93% (95% CI: 85%-97%), 12.22 (95% CI: 5.62-26.57), 0.09 (95% CI: 0.05-0.18), 126.99 (95% CI: 34.76-436.99) and 0.97 (95% CI: 0.95-0.98), respectively. Subgroup analysis revealed that CEMRI performed significantly better in prospective studies than in retrospective studies: 0.99 (95% CI: 0.96-1.00) vs. 0.95 (95% CI: 0.92-0.96) with P < 0.05. DATA CONCLUSION: Our meta-analysis suggested that CEMRI had high diagnostic efficacy in detecting residual or recurrent HCCs after TACE and may serve as an alternative method for further evaluation after TACE. LEVEL OF EVIDENCE: 5 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;52:1019-1028.

Evaluation of the feasibility of short-term electrodialysis for separating naturally occurring fluoride from instant brick tea infusion.

BACKGROUND: Removing excessive naturally occurring fluoride from tea and/or infusions is difficult because the process has low efficiency and causes secondary pollution. In this study, a novel electrodialysis (ED) technology was developed. We examined the effect of crucial parameters (electrolyte concentration, operation voltage, ED duration and initial concentration of the tea infusion) on defluoridation performance using a highly efficient ion-exchange membrane with five-compartment cells. RESULTS: The most effective ED system results were obtained at an electrolyte concentration of 10 g kg-1 and operating voltage of 20 V. Moreover, the fluoride removal capacity (10.70-66.93%) was highly dependent on the ED duration (1-15 min) and initial concentration of the tea infusion (0.5-10 g kg-1 ). The longer the ED duration and the lower the initial concentration, the higher was the defluoridation performance. During ED, limited loss of the main inclusions (total polyphenols, catechins, caffeine and selected ions) was observed. Furthermore, the D201 anion resin-filled ED stack (0.5-5 g) and improvement of concentrate compartment electrolyte (≥5 times the dilute compartment electrolyte) in the ED system enhanced the defluoridation rate significantly. CONCLUSION: ED is a potentially effective method that can be used for defluoridation in the deep processing of tea products. © 2019 Society of Chemical Industry.

Diagnostic accuracy of dual-source and 320-row computed tomography angiography in detecting coronary in-stent restenosis: a systematic review and meta-analysis.

BACKGROUND: Dual-source and 320-row computed tomography angiography (CTA) are increasingly used in diagnosing coronary in-stent restenosis (CISR). PURPOSE: We sought to perform this meta-analysis to evaluate the diagnostic accuracy of dual-source computed tomography angiography (DSCTA) and 320-row CTA in detecting CISR when compared to invasive coronary angiography. MATERIAL AND METHODS: Five scientific databases (PubMed, Embase, Scopus, The Cochrane Library, and Web of Science) were searched for research studies in which DSCTA and/or 320-row CTA were used as diagnostic tools for CISR, as recently as October 2017. Study inclusion, data extraction, systematic review, pooled meta-analysis, and subgroup analysis were conducted by two researchers independently. RESULTS: Thirteen studies with 1384 assessable stents on DSCTA and five studies including 622 assessable stents on 320-row CTA were finally included. The sensitivity, specificity, and area under the curve (AUC) of DSCTA in diagnosing CISR were 0.92 (0.87-0.96), 0.91 (0.87-0.94), and 0.97 (0.95-0.98), respectively, and they were 0.91 (0.82-0.96), 0.95 (0.88-0.98), and 0.96 (0.94-0.97) for 320-row CTA. Subgroup analysis result suggested that DSTCA performed significantly better in CISR detection when the stent diameter was ≥ 3 mm compared to stent diameter < 3 mm: 0.98 (0.97-0.99) vs. 0.82 (0.79-0.86) with P < 0.05. CONCLUSION: Our meta-analysis indicated both DSCTA and 320-row CTA had high diagnostic accuracy in detecting CISR and may serve as alternatives for further patient evaluation with CISR, especially for stent diameters ≥ 3 mm.

Comparison of diagnostic efficacy between CLE, tissue sampling, and CLE combined with tissue sampling for undetermined pancreaticobiliary strictures: a meta-analysis.

OBJECTIVE: The accurate diagnosis of undetermined pancreaticobiliary strictures remains challenging. Current ERCP-guided tissue sampling methods are of low sensitivity. Confocal laser endomicroscopy (CLE) is a new procedure and allows real optical biopsies that may improve the diagnosis of undetermined pancreaticobiliary strictures. The aim of this meta-analysis was to determine the diagnostic yield of CLE, tissue sampling, and CLE combined with tissue sampling for undetermined pancreaticobiliary strictures. METHOD: Pubmed, Embase, and the Cochrane Library database were reviewed for relevant studies. Pooled estimates of sensitivity and specificity with 95% confidence intervals (CIs) were calculated using the random-effects meta-analysis model. The summary receiver-operating characteristic (SROC) curve was constructed, and the area under the receiver operating characteristic curve (AUC) was calculated. RESULTS: Twelve studies involving 591 patients were enrolled in our analysis. The overall sensitivity and the specificity estimate of CLE for discriminating benign and malignant pancreaticobiliary strictures were 87% (95%CI, 83-91%) and 76% (95%CI, 70-81%), respectively. The AUC to assess the diagnostic efficacy was 0.8705. For tissue sampling, the overall sensitivity and the specificity estimate were 64% (95%CI, 57-70%) and 94% (95%CI, 90-97%), respectively. The AUC to assess the diagnostic efficacy was 0.8040. A combination of both methods increased the sensitivity (93%; 95%CI, 88-96%) with a specificity of 82% (95%CI, 74-89%). The AUC to assess the diagnostic efficacy was 0.9377. There was no publication bias by Deeks' Funnel Plot with p = .936. CONCLUSIONS: Compared with tissue sampling, CLE may increase the sensitivity for the diagnosis of malignant pancreaticobiliary strictures. A combination of both can effectively diagnose malignant pancreaticobiliary strictures.

Diagnostic accuracy of dual-source computed tomography angiography for the detection of coronary in-stent restenosis: A systematic review and meta-analysis.

We sought to perform a meta-analysis to comprehensively evaluate the diagnostic accuracy of dual-source computed tomography angiography (DSCTA) in detecting coronary in-stent restenosis (CISR) when compared to invasive coronary angiography. The stent-based research studies in which DSCTA was used as diagnostic tool for CISR, as recent as of October 2017, from several reputed scientific libraries (PubMed, Embase, Scopus, The Cochrane Library, and Web of Science) were evaluated. Study inclusion, data extraction, and risk bias assessment were conducted by two researchers independently. Pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under summary receiver operator characteristics (SROC) curve (AUC) were calculated to assess the diagnostic value. In addition, heterogeneity and subgroup analysis were also carried out. A total of 13 studies with a total of 894 patients and 1384 assessable stents were included. The pooled results of DSCTA diagnosing CISR were as follows: SEN 0.92 (95% confidence interval [CI] 0.87-0.96), SPE 0.91 (95% CI 0.87-0.94), PLR 9.83 (95% CI 6.93-13.94), NLR 0.09 (95% CI 0.05-0.15), DOR 114.73 (95% CI 64.12-205.28), and AUC 0.97 (95% CI 0.95-0.98), respectively. The subgroup analysis result suggested that DSTCA performed significantly better in CISR detection when the stent diameter was ≥3 mm compared with the stent diameter <3 mm: (0.98 [0.97-0.99] vs 0.82 [0.79-0.86]) with P < .05. This study revealed that DSCTA has excellent diagnostic performance for detecting CISR and may serve as an alternative for further patient evaluation with CISR, especially for stent diameter ≥3 mm.

[The effect of lnc-RAP3 on 3T3-L1 preadipocyte differentiation in mouse].

The long non-coding RNAs (lncRNAs) are a type of RNAs with more than 200nt in length and without any long open reading frame, but often have mRNA structural features. They can regulate the expression of target genes in different manners at the transcriptional and post-transcriptional levels. In recent years, various studies demonstrated that lncRNAs play crucial roles in adipogenesis. The long non-coding RNA, lnc-RAP3, located on the mouse chromosome 17, possesses a significantly differential expression pattern during mouse adipocyte differentiation; but its specific biological function (s) remains unclear. To investigate the effect of lnc-RAP3 on adipogenesis in the mouse 3T3-L1 preadipocytes, we first constructed a eukaryotic expression vector pcDNA3.1-RAP3. pcDNA3.1-RAP3 and synthetic RAP3-siRNAs were transfected individually into 3T3-L1 preadipocytes by Lipofectamine TM 2000, thereby over-expressing and knocking-down lnc-RAP3 expression, respectively. The transfected preadipocytes were induced to undergo adipogenic differentiation. Oil Red O staining and qRT-PCR were used to detect the effects of lnc-RAP3 overexpression/knockdown on 3T3-L1 preadipocyte differentiation. The results showed that overexpression of lnc-RAP3 led to a notable decrease in lipid accumulation (P<0.05) and remarkably reduced the mRNA expression levels of C/EBPα, Glut4, PPARγ, LPL and FAS on day 0, day 2, and day 4 post differentiation (P<0.05, P<0.01). In contrast, quantitative analysis of Oil Red O on day 4 of differentiation revealed that inhibition of lnc-RAP3 increased the formation of neutral lipid droplets (P<0.05). In addition, silencing lnc-RAP3 also significantly increased the mRNA expression of PPARγ, LPL, C/EBPα, FAS and Glut4 on day 0 and day 2 post differentiation (P<0.05, P<0.01). Our study suggests that lnc-RAP3 might suppress 3T3-L1 preadipocyte differentiation by affecting the expression of the genes involved in adipogenic differentiation.

I2/CHP mediated [1 + 1 + 1 + 1] cyclization of aromatic isocyanides with amines to construct 1,3-diazetidine-2,4-diimine derivatives.

An I2/CHP (cumene hydroperoxide) mediated [1 + 1 + 1 + 1] cyclization of aromatic isocyanides with readily accessible amines via the formation 4 new C-N bonds has been developed to construct unsymmetric 1,3-diazetidine-2,4-diimine derivatives under mild conditions.

[Structure and function of insulin-like growth factor acid-labile subunits in mammalian homologues].

Insulin-like growth factors (IGFs) act as a critical signaling pathway in animals and play significant roles in body growth, development, and occurrence and progression of animal diseases. In the past, structural and functional studies of ligands, receptors and even specific binding proteins in the IGFs system have been extensively investigated. However, the functional study of insulin-like growth factor acid-labile subunit (IGFALS) mainly focused on the prolonging half-life of IGFs. Increasing number of studies indicated that mutations in the IGFALS DNA sequence and low expression level of IGFALS proteins can lead to growth and development retardation in animals. In this review, we summarize recent structural and functional studies of IGFALS in mammals, aiming to further identify detailed genetic mechanism of IGFALS.

[Laser Induced Fluorescence Spectroscopic Analysis of Aromatics from One Ring to Four Rings].

In order to distinguish small aromatics preferably, a Nd : YAG Laser was used to supply an excitation laser, which was adjusted to 0.085 J x cm(-2) at 266 nm. Benzene, toluene, naphthalene, phenanthrene, anthracene, pyrene and chrysene were used as the representative of different rings aromatics. The fluorescence emission spectra were researched for each aromatic hydrocarbon and mixtures by Laser induced fluorescence (LIF). Results showed that the rings number determined the fluorescence emission spectra, and the structure with same rings number did not affect the emission fluorescence spectrum ranges. This was due to the fact that the absorption efficiency difference at 266 nm resulted in that the fluorescence intensities of each aromatic hydrocarbon with same rings number were different and the fluorescence intensities difference were more apparently with aromatic ring number increasing. When the absorption efficiency was similar at 266 nm and the concentrations of each aromatic hydrocarbon were same, the fluorescence intensities were increased with aromatic ring number increasing. With aromatic ring number increasing, the fluorescence spectrum and emission peak wavelength were all red-shifted from ultraviolet to visible and the fluorescence spectrum range was also wider as the absorption efficiency was similar. The fluorescence emission spectra from one to four rings could be discriminated in the following wavelengths, 275 to 320 nm, 320 to 375 nm, 375 to 425 nm, 425 to 556 nm, respectively. It can be used for distinguish the type of the polycyclic aromatic hydrocarbons (PAHs) as it exists in single type. As PAHs are usually exist in a variety of different rings number at the same time, the results for each aromatic hydrocarbon may not apply to the aromatic hydrocarbon mixtures. For the aromatic hydrocarbon mixtures, results showed that the one- or two-ring PAHs in mixtures could not be detected by fluorescence as three- or four-ring PAHs existed in mixture. This was caused by radiation energy transfer mechanism, in which the ultraviolet light was lost in mixtures but the fluorescence intensities were increased with the one- or two-ring PAHs adding. When the mixture only contained three- and four-ring PAHs, the fluorescence emission spectrum showed the both characteristics of three- and four-ring PAHs fluorescence. When three- and four-ring PAHs existed in mixtures at the same time, the fluorescence emission spectra were related to each concentration, so the rings number could be discriminated to a certain extent.

[Research on Spectrum Radiation Characteristics of a New Type Infrared/ Ultraviolet Dual Color Decoy].

The advantage of traditional MTV infrared decoys which are mainly consist of magnesium, Teflon and VITON is that it emits high radiant energy, so it is an effective countermeasure to traditional seekers which seek the target by heat source. The spectral radiant intensity which generated from high temperature combustion of MTV infrared decoys in near infrared region and ultraviolet band is very high, and that in Mid-IR region is relative lower, however the radiant intensity of real jet fighter in ultraviolet band is low and the infrared radiant intensity ratio of Mid-IR to near IR band is greater than 1. Thus, the traditional MTV infrared decoys are hardly able to counter the seekers equipped with dual color combined guidance system. Based on the spectral matching principle, we designed and prepared a new infrared/ultraviolet dual color decoy which is mainly consist of oxidant (wt% 45-75), fuel (wt% 10-25), energetic binder (wt% 25-50) and additives. We conducted theoretical calculations on combustion products of the reagent combinations using CEA (Chemic equilibrium & Application) software and initially determined the content of each component of the decoy formulation on the basis of the calculations results, then investigated the infrared radiation characteristics of decoys employing SR5000 spectrum radiometer and remote sensing interferometer spectrometer Tensor37 and analyzed the possible reasons for test results difference of the two systems separately from the test principle and calculation method, the testing environment, stability of testing results and other aspects. We studied the ultraviolet radiation characteristics of decoys using S2000 fiber optical spectrometer and the test results were consistent with the fighter ultraviolet radiant intensity which gained from theoretical calculation. We researched on the temperature characteristics of decoys by Imager IR 8325 mid-infrared thermal imager and it turned out that the dual color decoy is similar to the real fighter target in temperature characteristics. The results indicates that the infrared radiant intensity ratio of Mid-IR to near IR band is from 1 to 3 (1< I(3-5 microm) : I(1-3 microm) <3). The infrared radiant intensity in 3-5 pLm band is tunable from 0.9 to 2.5 kW x sr(-1) while the ultraviolet radiant intensity in 0.3-0.5 microm is about (20 +/- 5)W x sr(-1). The flame temperature is between 850-1100 degrees C. It is proved that the dual color decoy as-designed has excellent characteristics.

25 Gb/s transmission over 820 m of MMF using a multimode launch from an integrated silicon photonics transceiver.

A new high bandwidth bend-insensitive MMF optimized for 1310 nm is designed and characterized. 25 Gb/s transmission over a record 820 m length using a multimode launch from an integrated SiPh transceiver at 1310 nm through the new fiber is demonstrated with a power penalty of 3.4 dB at 10(-12) BER. Detailed characteristics of the fiber and transceiver are presented along with BER measurements.

The deterministic chaos and random noise in turbulent jet.

A turbulent flow is usually treated as a superposition of coherent structure and incoherent turbulence. In this paper, the largest Lyapunov exponent and the random noise in the near field of round jet and plane jet are estimated with our previously proposed method of chaotic time series analysis [T. L. Yao, et al., Chaos 22, 033102 (2012)]. The results show that the largest Lyapunov exponents of the round jet and plane jet are in direct proportion to the reciprocal of the integral time scale of turbulence, which is in accordance with the results of the dimensional analysis, and the proportionality coefficients are equal. In addition, the random noise of the round jet and plane jet has the same linear relation with the Kolmogorov velocity scale of turbulence. As a result, the random noise may well be from the incoherent disturbance in turbulence, and the coherent structure in turbulence may well follow the rule of chaotic motion.