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Background: Atrial fibrillation (AF) is acknowledged as a disease continuum. Despite catheter ablation being recommended as a primary therapy for AF, the high recurrence rates have tempered the initial enthusiasm. Insulin resistance (IR) has been established as an independent predictor for the onset of AF. However, the correlation between non-insulin-based IR indices and late AF recurrence in patients undergoing radiofrequency catheter ablation remains unknown. Methods: A retrospective cohort of 910 AF patients who underwent radiofrequency catheter ablation was included in the analysis. The primary endpoint was late AF recurrence during the follow-up period after a defined blank period. The relationship between non-insulin-based IR indices and the primary endpoint was assessed using multivariate Cox hazards regression models and restricted cubic splines (RCS). Additionally, the net reclassification improvement and integrated discrimination improvement index were calculated to further evaluate the additional predictive value of the four IR indices beyond established risk factors for the primary outcome. Results: During a median follow-up period of 12.00 months, 189 patients (20.77%) experienced late AF recurrence, which was more prevalent among patients with higher levels of IR. The multivariate Cox hazards regression analysis revealed a significant association between these IR indices and late AF recurrence. Among the four indices, METS-IR provided the most significant incremental effect on the basic model for predicting late AF recurrence. Multivariable-adjusted RCS curves illustrated a nonlinear correlation between METS-IR and late AF recurrence. In subgroup analysis, METS-IR exhibited a significant correlation with late AF recurrence in patients with diabetes mellitus (HR: 1.697, 95% CI 1.397 − 2.063, P < 0.001). Conclusion: All the four non-insulin-based IR indices were significantly associated with late AF recurrence in patients undergoing radiofrequency catheter ablation. Addressing IR could potentially serve as a viable strategy for reducing the late AF recurrence rate. [ABSTRACT FROM AUTHOR]

Background. Whether statins can reduce major cardiovascular adverse events (MACE) in patients with coronary artery spasm (CAS) is controversial. And most of the relevant research to date has been conducted in Asia. Methods. We systematically searched electronic databases for studies on the effect of statins on MACE in patients with CAS in Asia and published up to September 2022. We included data on MACE in a statin therapy patient group and a no-statin therapy control group. We then evaluated the effect of statin therapy on MACE in patients with CAS in Asia by meta-analysis and trial sequential analysis (TSA). All statistical analyses were performed using Stata 16.0 software and TSA software. Results. A total of 10 studies (n = 9333 patients) were included in the final analysis. Meta-analysis showed that the use of statins had a significant effect on MACE in CAS patients (with RR, 0.70; 95% CI, 0.49-0.99), and the sensitivity analysis further confirmed this finding. Subgroup analysis suggested that the correlation between statin therapy and reduced MACE endpoint was stronger in Japanese patients and patients followed up for more than 4 years. But our TSA results indicated that the available samples were insufficient and further research is needed. Conclusions. Our meta-analysis suggests that statin therapy can reduce MACE in patients with CAS in Asia, and the correlation between the two was stronger in Japanese patients and patients followed up for more than 4 years. [ABSTRACT FROM AUTHOR]

The direct graphite-to-diamond transformation mechanism has been a subject of intense study and remains debated concerning the initial stages of the conversion, the intermediate phases, and their transformation pathways. Here, we successfully recover samples at the early conversion stage by tuning high-pressure/high-temperature conditions and reveal direct evidence supporting the nucleation-growth mechanism. Atomistic observations show that intermediate orthorhombic graphite phase mediates the growth of diamond nuclei. Furthermore, we observe that quenchable orthorhombic and rhombohedra graphite are stabilized in buckled graphite at lower temperatures. These intermediate phases are further converted into hexagonal and cubic diamond at higher temperatures following energetically favorable pathways in the order: graphite → orthorhombic graphite → hexagonal diamond, graphite → orthorhombic graphite → cubic diamond, graphite → rhombohedra graphite → cubic diamond. These results significantly improve our understanding of the transformation mechanism, enabling the synthesis of different high-quality forms of diamond from graphite. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: In this systematic review and meta‐analysis, we aimed to validate the predictive role of atrial fibrillation (AF) termination in long‐term arrhythmia recurrence. Method: Our search encompassed databases including MEDLINE, EMBASE, PubMed, and the Cochrane Library up to August 1, 2021. Three independent reviewers conducted screening and data extraction. The data included ablation strategy, recurrence mode, AF termination mode, numbers of patients, and recurrence cases in the termination and nontermination groups. The primary endpoint was the recurrence of atrial arrhythmia at long‐term follow‐up (≥ 12 months). Results: Our analysis included 22 publications, with 11 prospective studies being eligible for further meta‐analysis. Among these, 14 studies reported significantly lower rates of arrhythmia recurrence in the AF termination group compared to the nontermination group. Among seven studies involving 1114 patients that examined single procedure outcomes, the pooled estimated effect was RR 0.78 (95% CI 0.68–1.90) with an I2 value of 57%. Subgroup analysis focusing on termination mode as sinus rhythm yielded a pooled estimated effect of RR 0.74 (95% CI 0.59–0.92) with an I2 value of 47%. Additionally, analysis of seven studies involving 1433 patients for repeat procedures demonstrated a significant preference for the AF termination group (RR 0.83, 95% CI 0.71–0.97, I2 = 84%). Subgroup analysis indicated reduced heterogeneity when the termination mode was sinus rhythm (RR 0.68, 95% CI 0.51–0.90, I2 = 57%). Conclusion: Our study establishes that AF termination serves as an effective predictor for the success of persistent AF ablation procedures. This finding holds potential implications for clinical practice and contributes to our understanding of long‐term arrhythmia recurrence in the context of AF termination. [ABSTRACT FROM AUTHOR]

Background: There is limited available data regarding the impact of cycle length (CL) prolongation when converting atrial fibrillation (AF) to organized atrial tachycardia (AT) and its effect on clinical outcomes. Methods and Method: We retrospectively screened and included a cohort of 132 patients with persistent or long‐standing persistent AF who underwent circumferential pulmonary vein isolation (CPVI) and left atrial substrate modification (LASM) between January 2015 and October 2019. In all 132 consecutive patients, persistent AF was successfully converted into organized AT. For cases with recurrence after a 3‐month blanking period, a repeat procedure was conducted. Results: We observed a notable prolongation in CL after ablation (average increase of 56.6 ± 30 ms). Following a median follow‐up duration of 9.5 ± 5.1 months, 27 patients experienced recurrence. Through receiver operating curve (ROC) analysis, a prolonged CL cut‐off of 42.5 ms was identified, with a specificity of 71% and a sensitivity of 59.4%. Patients were categorized into two groups: those with CL less than 42.5 ms (group A, n = 48) and those with CL more than 42.5 ms (group B, n = 84). The Kaplan–Meier survival curves demonstrated a significantly higher recurrence‐free rate after catheter ablation in group B compared to group A (p = 0.002). Conclusions: Upon termination of persistent AF into AT during ablation, it was found that CL prolongation beyond 42.5 ms was associated with improved freedom from arrhythmia. [ABSTRACT FROM AUTHOR]

The streak tubes with a large effective photocathode area, large effective phosphor screen area, and high photocathode radiant sensitivity are essential for improving the field of view, depth of field, and detectable range of the multiple-slit streak tube imaging lidar. In this paper, a high spatial resolution, large photocathode area, and compact meshless streak tube with a spherically curved cathode and screen is designed and tested. Its spatial resolution reaches 20 lp/mm over the entire Φ28 mm photocathode working area, and the simulated physical temporal resolution is better than 30 ps. The temporal distortion in our large-format streak tube, which is shown to be a non-negligible factor, has a minimum value as the radius of curvature of the photocathode varies. Furthermore, the photocathode radiant sensitivity and radiant power gain reach 41 mA/W and 18.4 at the wavelength of 550 nm, respectively. Most importantly, the external dimensions of our streak tube are no more than Φ60 mm × 110 mm. [ABSTRACT FROM AUTHOR]

The streak tubes with a large effective photocathode area, large effective phosphor screen area, and high photocathode radiant sensitivity are essential for improving the field of view, depth of field, and detectable range of the multiple-slit streak tube imaging lidar. In this paper, a high spatial resolution, large photocathode area, and compact meshless streak tube with a spherically curved cathode and screen is designed and tested. Its spatial resolution reaches 20 lp/mm over the entire Φ28 mm photocathode working area, and the simulated physical temporal resolution is better than 30 ps. The temporal distortion in our large-format streak tube, which is shown to be a non-negligible factor, has a minimum value as the radius of curvature of the photocathode varies. Furthermore, the photocathode radiant sensitivity and radiant power gain reach 41 mA/W and 18.4 at the wavelength of 550 nm, respectively. Most importantly, the external dimensions of our streak tube are no more than Φ60 mm × 110 mm. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the impact of Ang-(1–7) on calcium transient (CaT) in cardiomyocytes during the pathogenesis of heart failure. Cardiac dysfunction was induced by ligation of left anterior descending coronary artery in adult SD rats. Randomly selected rats were ligated and continuously infused with Ang-(1–7) [HF + Ang-(1–7) group] or saline (HF + saline group) via osmotic minipumps. After 28 days, hemodynamic parameters, the CaT, and the heart rate threshold of CaT alternans (CaT-Alt) were measured. Continuous Ang-(1–7) treatment could attenuate the impairment of cardiac function following LAD ligation. The amplitudes (F/F 0 ) and 50%/90% recovery time of CaT were significantly different among HF + saline, HF + Ang-(1–7) and Sham-operated group. Compared to the Sham-operated group, the HF + saline group showed decreased CaT amplitude, and a prolonged 50%/90% CaT recovery time; Ang-(1–7) significantly improved these abnormalities. Compared with Sham-operated group, heart rate thresholds of CaT-Alt significantly reduced in HF + saline group, and Ang-(1–7) partly restored it. These findings indicate that Ang-(1–7) attenuates the CaT disturbance and increases the heart rate threshold of CaT-Alt during the pathogenesis of ischemic heart failure. [ABSTRACT FROM AUTHOR]

By adopting the development method and diagnostic architecture of automotive open system architecture standard AUTOSAR, an automotive electronic fault diagnostic system based on Freescale HCS12X processor is developed and corresponding simulation experiments are conducted. The results show that the system can timely and accurately diagnose malfunctions, and the AUTOSAR-based diagnostic system is configurable and can adapt to a variety of situations. [ABSTRACT FROM AUTHOR]

Abstract: Doublecortin-immunoreactive (DCX+) cells were detected across the allo- and neo-cortical regions in the adult guinea pig cerebrum, localized to layer II specifically at its border with layer I. The density of labeled cells declined with age, whereas no apparent apoptotic activity was detectable over the cortex including layer II. DCX+ cells varied in somal size, labeling intensity, nuclear appearance, and complexity of processes. These cells were often arranged in clusters with cells of similar morphology sometimes packed tightly together. They exhibited complete colocalization with polysialylated neural cell adhesion molecule (PSA-NCAM) and neuron-specific type III β-tubulin (TuJ1). Medium to large-sized DCX+ cells had well-developed neuritic processes, and expressed neuron-specific nuclear protein (NeuN). Large mature-looking cells with weak DCX reactivity invariably displayed heavy NeuN reactivity, implicating a transitional stage of these labeled cells. These “transitional” cells also consistently exhibited weak reactivity for γ-aminobutyric acid (GABA), glutamate decarboxylase (GAD67), β-nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) and neuronal nitric oxide synthase (nNOS), suggestive of them being young GABAergic/nitrinergic interneurons. Our data indicate that DCX+ cells exist widely in the adult guinea pig cerebral cortex, with a predominant localization in upper layer II. The morphological variation and differential expression of neuronal markers in these cells implicate that they might be developing neurons, and that they are probably differentiating into GABAergic interneurons. This population of cells might be involved in interneuron plasticity in the adult mammalian cerebral cortex. [Copyright &y& Elsevier]

Abstract: The optical anisotropic states in the azo-dye Disperse Red 13 doped poly(methyl methacrylate) polymeric film are induced by polarized light and the nonlinear refractive index in these states are studied by the Z-scan technique. It is found that the n 2 of the sample can be controlled by changing both the polarization direction and the intensity of the 514nm light. Photo-induced isomerization and reorientation of azo chromophores in polymer matrices are used to explain the results. [ABSTRACT FROM AUTHOR]

Visualizing ultrafast dynamics at the atomic scale requires time-resolved characterization with femtosecond temporal resolution. For fully relativistic electron bunch probes, existing techniques for single-shot ultrafast electron diffraction (UED) are limited by the achievable electron probe bunch length, charge, and timing jitter. We present the first experimental demonstration of dual-fed THz-driven compression and time-stamping that enables electron probes with improved temporal resolution. This technique utilizes two counter-propagating quasi-single-cycle THz pulses generated from two OH-1 organic crystals coupled into an optimized THz compressor structure. We demonstrate electron bunch compression and time-of-arrival jitter suppression by a factor of 3 paving the way toward unique opportunities for UED time-resolved measurements. [ABSTRACT FROM AUTHOR]

Hierarchical domain structures associated with oxygen octahedra tilting patterns were observed in lead-free (Bi1/2Na1/2)TiO3 ceramics using aberration-corrected high-resolution transmission electron microscopy (HRTEM). Three types of domains are induced by distinct mechanisms: the 'orientation-domain' is induced at micrometer scale formed by different tilting orientations of the oxygen octahedra, the 'meso-chemical-domain' occurs at a few tens of nanometer scale by chemical composition variation on the A-site in the ABO3 perovskite structure, and the 'nano-cluster-region' runs across several unit-cells with apparent A-site cation segregation with oxygen vacancies clustering around Na cations. Based on HRTEM amplitude contrast imaging (ACI), the correlation between the oxygen octahedral tilting pattern and compositional non-stoichiometry was established. The role of the hierarchical domain structure associated with the tilting patterns of the oxygen octahedra on the ferroelectric behavior of (Bi1/2Na1/2)TiO3 is also discussed. [ABSTRACT FROM AUTHOR]

• A multimodal fusion-based compressed ultrafast photography was proposed, which simultaneously records the same dynamic scene with different imaging modes. • Transient images were first utilized to assist in the reconstruction of CUP. • An untrained neural network-based reconstruction algorithm was proposed for conducting image reconstruction of MF-CUP. • The superiority of the proposed method in temporal and spatial fidelity was verified in simulations and experiments. Featuring high frame rate and large sequence depth in a single shot, compressed ultrafast photography (CUP) has emerged as an outstanding tool for observing ultrafast phenomena, especially those unrepeatable or irreversible ones. However, the lower image quality in CUP due to high data compressive ratio has always been a tough issue, hampering its further applications in capturing the transient scenes with fine structural information. To overcome this disadvantage in CUP, here we report a multimodal fusion-based compressed ultrafast photography to achieve high-fidelity ultrafast imaging, termed MF-CUP. MF-CUP simultaneously records the dynamic scenes with three different imaging models, involving CUP, transient imaging and spatiotemporal integration imaging. Attributed to the joint acquisition of the dynamic scenes from different imaging models and the multimodal fusion image reconstruction algorithm enabled by untrained neural network, MF-CUP acquires the higher fidelity in both spatial and temporal domains compared with traditional CUP. Both the simulation and experimental results demonstrate that MF-CUP can effectively enhance the accuracy and quality of reconstructed images. Given this high-fidelity imaging ability of MF-CUP, it will provide a powerful tool for the detection of ultrafast dynamics with fine details. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) is a ubiquitous group of organic compounds in rainwater that plays vital roles in the biogeochemical cycle. However, little is known about its chemical composition, optical characterization, potential sources, and controlling mechanisms in peri-urban atmospheric rainwater. One-year rainfall samples were collected between September 2018 and August 2019 in a Nanjing suburb. Stoichiometric, ultraviolet–visible (UV–Vis) absorption, and three-dimensional fluorescence excitation-emission matrix (EEM) with parallel factor analysis (PARAFAC) analyses were utilized to characterize DOM. Several proxies for DOM concentration, including dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and absorption coefficient (a254), exhibited power-function relationships with the rainfall amount (r2 = 0.33–0.55, p < 0.001). Particularly, the DOC and a254 value showed significant seasonal variability, with lower value in two wet seasons (winter and summer) than in the dry seasons (autumn and spring). The annual wet depositional (WD) flux of DOC in the Xianlin (XL) site was calculated as 1.68 g C m−2 yr−1, agreeing with the range of global WD flux values. Two terrestrial humic-like components (C1–C2), one microbial humic-like component (C3), and one tryptophan-like component (C4) were identified by EEM-PARAFAC in rainwater DOM. The results of the specific absorption indices (SUVA 254, S R) and PARAFAC component analyses revealed that summer DOM samples had lower fluorescence intensities, aromatic contents, and molecular sizes. Principal component analysis (PCA) based on DOM indices showed that rainwater DOM had predominantly terrestrial humic origins, while this characteristic became slightly weaker in summer. The quantity and quality of rainwater DOM were closely related to meteorological variables (i.e., air mass, rainfall amount, and solar radiation) as well as anthropogenic activities. This study could improve the understanding of the quantity and quality of rainwater DOM on carbon budgets and biogeochemical cycling from some new insights of optical proxies about different fates of rainwater DOM under complex controlling mechanisms. Image 1 • Concentration and chemical structure of rainwater DOM showed seasonal variations. • Climatic factors and human activities were dominant effects on rainwater DOM. • Rainwater DOM components were mainly generated from humic substances. • Wet inorganic N in atmosphere was closely coupled with rainwater DOM. [ABSTRACT FROM AUTHOR]

Abstract Perovskite oxides are promising multi-functional materials with enhanced physical and chemical properties. In this study, high-crystalline SrMnO 3 perovskite oxide nanofibers have been successfully synthesized by sol–gel electrospinning followed by calcination at different temperatures, using polyvinylpyrrolidone as a sacrificial polymeric binder. The change in porosity and grain size with calcination temperature imparted a substantial effect on the electrochemical properties of the obtained SrMnO 3 nanofibers. The SrMnO 3 nanofiber electrode calcined at 700 °C exhibits an electrochemical capacitance of 321.7 F g−1 at a discharge current density of 0.5 A g−1. The effect of doping Ba/Ca on Sr, and Co/Fe/Ni on Mn, respectively, on the specific capacitance of SrMnO 3 nanofibers is studied. 20 mol% Ba loading shows the best performance as a supercapacitor electrode with a specific capacitance of 446.8 F g−1 at a discharge current density of 0.5 A g−1. The nanofibers retained 87% its initial capacitance after 5000 successive cycles. The device fabricated using the nanofibers show an energy density of 37.3 W h kg−1 at a power density of 400 W kg−1, and it is retained as 15.7 W h kg−1 even at a high-power density of 8006 W kg−1, indicating the potential of this electrode material for high-rate charge/discharge operations in supercapacitors. Graphical abstract fx1 Highlights • The first study of SrMnO 3 perovskite nanofibers for supercapacitor application. • Evaluation of effects of Ba, Ca, Co, Fe and Ni doping and doping levels. • High capacitance of 446.8 F g-1 of SrMnO 3 doped with 20% Ba at a discharge current density of 0.5 A g−1. • Energy density of 37.3 W h kg−1 at power density of 400 W kg−1 which is retained as 15.7 W h kg−1 at 8006 W kg−1. • High cycling stability retaining 87% of its initial capacitance after 5000 successive cycles. [ABSTRACT FROM AUTHOR]

Azo dyes with different pull/push substituents are selected as photosensitive molecules. Guest-host amorphous azo polymer samples are prepared by doping these azo dyes directly in poly(methyl methacrylate) polymeric matrices. Nonlinear optical properties of these pull/push type azo dye-doped polymers are investigated using the Z-scan experiment. The influence of the pull/push substituents and the azo dye concentration on the nonlinear optical property is studied. [ABSTRACT FROM AUTHOR]

A type of all-optical logical gate based on two kinds of refractive index grating in azo-dye doped polymer film is studied in this paper. Using interference recording method with two 532nm laser beams, the transient refractive gratings can be formed in poly(methyl methacrylate) (PMMA) films containing azo-dye Disperse Red 13 (DR13). The characteristics of the transient gratings in films which are recorded by two 532nm laser beams with different polarization states are investigated by monitoring the first-order diffraction intensity of the readout He-Ne laser beam (632.8nm). It is found that the transient gratings in the polymeric films can be established and decayed in several seconds. Furthermore, we realize XOR and XNOR all-optical logical operation based on the relationship among the polarization states of the recording beams, the reading beam, and the diffraction beam. [ABSTRACT FROM AUTHOR]

Abstract: DCX-immunoreactive (DCX+) cells occur in the piriform cortex in adult mice and rats, but also in the neocortex in adult guinea pigs and rabbits. Here we describe these cells in adult domestic cats and primates. In cats and rhesus monkeys, DCX+ cells existed across the allo- and neocortex, with an overall ventrodorsal high to low gradient at a given frontal plane. Labeled cells formed a cellular band in layers II and upper III, exhibiting dramatic differences in somal size (5–20 μm), shape (unipolar, bipolar, multipolar and irregular), neuritic complexity and labeling intensity. Cell clusters were also seen in this band, and those in the entorhinal cortex extended into deeper layers as chain-like structures. Densitometry revealed a parallel decline of the cells across regions with age in cats. Besides the cellular band, medium-sized cells with weak DCX reactivity resided sparsely in other layers. Throughout the cortex, virtually all DCX+ cells co-expressed polysialylated neural cell adhesion molecule. Medium to large mature-looking DCX+ cells frequently colocalized with neuron-specific nuclear protein and γ-aminobutyric acid (GABA), and those with a reduced DCX expression also partially co-labeled for glutamic acid decarboxylase, parvalbumin, calbindin, β-nicotinamide adenine dinucleotide phosphate diaphorase and neuronal nitric oxide synthase. Similar to cats and monkeys, small and larger DCX+ cells were detected in surgically removed human frontal and temporal cortices. These data suggest that immature neurons persist into adulthood in many cortical areas in cats and primates, and that these cells appear to undergo development and differentiation to become functional subgroups of GABAergic interneurons. [Copyright &y& Elsevier]

Particulate organic carbon (POC) sources, which regulate dissolved organic carbon, sediment organic carbon, and inorganic carbon via deposition, degradation, and mineralization, play an important role in lake ecosystems. Linear or Bayesian algorithms on isotope and n-alkanes have been widely used to identify the source proportion of organic carbon. However, the applicability of these methods is ambiguous because of the unilateral advantages of each model and trace factors. To test the applicability of the various methods for identifying POC sources, we analyzed dual isotopes and n-alkanes in surface water samples of Lake Taihu, and Multi-source mixing model and Bayesian mixing model were used to distinguish between endogenous and exogenous contributions. Carbon isotope presented a clear advantage in West Taihu (-21.85 ± 0.78‰) and Southwest Taih (-22.61 ± 1.35‰); nitrogen isotope also showed high values in Meiliang Bay (9.76 ± 0.92‰). The majority of the lake was dominated by short-chain n-alkanes, except for East Taihu Lake (dominated by medium-chain n-alkanes) and areas with riverine input (dominated by long-chain n-alkanes). Different principles between the Bayesian mixing model (based on the Markov Chain Monte Carlo algorithm) and the Multi-source mixing model (based on linear estimation) caused discrepancies in the estimations of source contributions. But the fraction of chemical compounds during the migration process, and the overlap of potential sources play important role in the inconsistency of results. The estimations from the different models were consistent in indicating the dominance of endogenous organic carbon in Lake Taihu (mean of 60.18 ± 20.26%), particularly in the north and western regions (West Taihu, Meiliang Bay, and Southwest Taihu). This was likely due to algal aggregation influenced by human activities and climatic factors. [ABSTRACT FROM AUTHOR]

Sixteen polycyclic aromatic hydrocarbons (PAHs) in a sediment core from Dianchi Lake, southwest China, were analysed. The influence of changes in China's energy structure for 2–6 ringed PAHs was investigated to assess sources and the impact of socioeconomic development on temporal changes in concentrations. The concentration of the ΣPAH 16 ranged from 746 to 2293 ng g−1. Prior to the 1960s relatively low concentrations of the ΣPAH 16 and a larger proportion of 2–3-ring PAHs indicated that biomass combustion was the main source of PAHs. A rapid increase in the concentrations of 2–3 ring PAHs between 1975 and 2004 was attributed to population growth and coal consumption. A declining trend since 2004 was interpreted as being due to local changes in household energy usage. Increased concentrations of 4-ring PAH between 1975–2005 and 5–6-ring PAHs between the 1980s to 2004 showed correlations with increased coal consumption and the number of motor vehicles, respectively. These were caused by rapid urbanization and industrialization in the Dianchi watershed following the implementation of the Reform and Open Policy in 1978. A subsequent decline in the concentrations of 4-ring and 5–6-ring PAHs may have been due to decreased coal consumption and improvements in emission standards, respectively. Source apportionment by a PMF model revealed that coal combustion (29.2%), vehicle emissions (24.2%), petrogenic sources (21.8%), and biomass combustion (24.9%) were the sources of PAHs in the lake sediment core, and that coal combustion was the most important regional source of PAHs pollution. Image 1 • Sixteen PAHs from Dianchi lake sediment, a plateau lake in China, were studied. • Sediment record of PAHs reflect trends in GDP and total energy consumption. • Sediment records of different PAH rings can reflect the changes of energy structure. • Coal and biomass combustion, vehicle emissions and petrogenic were the PAHs sources. • Time trend of factor contributions are consistent with economic parameters. [ABSTRACT FROM AUTHOR]

Amorphous bulk composites were prepared by doping azo-dye Disperse Red 13 (DR13) in poly(methyl methacrylate) (PMMA) matrices. Photo-induced anisotropy of such kind of bulk polymer material was investigated experimentally by measuring the birefringence when irradiating it with linearly polarized green light. We report the first observation of self-trapping of an optical vortex based on such effect in bulk poly(methyl methacrylate) materials containing photosensitive azo-dye molecules. The dependence of the average core width of a single-charge optical vortex versus time and input power was investigated in detail. [ABSTRACT FROM AUTHOR]