Heavy metal induced shifts in microbial community composition and interactions with dissolved organic matter in coastal sediments.

Heavy metals can impact the structure and function of coastal sediment. The dissolved organic matter (DOM) pool plays an important role in determining both the heavy metal toxicity and microbial community composition in coastal sediments. However, how heavy metals affect the interactions between microbial communities and DOM remains unclear. Here, we investigated the influence of heavy metals on the microbial community structure (including bacteria and archaea) and DOM composition in surface sediments of Beibu Gulf, China. Our results revealed firstly that chromium, zinc, cadmium, and lead were the heavy metals contributing to pollution in our studied area. Furthermore, the DOM chemical composition was distinctly different in the contaminated area from the uncontaminated area, characterized by a higher average O/C ratio and increased prevalence of carboxyl-rich alicyclic molecules (CRAM) and highly unsaturated compounds (HUC). This indicates that DOM in the contaminated area was more recalcitrant compared to the uncontaminated area. Except for differences in archaeal diversity between the two areas, there were no significant variations observed in the structure of archaea and bacteria, as well as the diversity of bacteria, across the two areas. Nevertheless, our co-occurrence network analysis revealed that the B2M28 and Euryarchaeota, dominating bacterial and archaeal groups in the contaminated area were strongly related to CRAM. The network analysis also unveiled correlations between active bacteria and elevated proportions of nitrogen-containing DOM molecules. In contrast, the archaea-DOM network exhibited strong associations with nitrogen- and sulfur-containing molecules. Collectively, these findings suggest that heavy metals indeed influence the interaction between microbial communities and DOM, potentially affecting the accumulation of recalcitrant compounds in coastal sediments.

A spatiotemporal atlas of mouse liver homeostasis and regeneration.

The mechanism by which mammalian liver cell responses are coordinated during tissue homeostasis and perturbation is poorly understood, representing a major obstacle in our understanding of many diseases. This knowledge gap is caused by the difficulty involved with studying multiple cell types in different states and locations, particularly when these are transient. We have combined Stereo-seq (spatiotemporal enhanced resolution omics-sequencing) with single-cell transcriptomic profiling of 473,290 cells to generate a high-definition spatiotemporal atlas of mouse liver homeostasis and regeneration at the whole-lobe scale. Our integrative study dissects in detail the molecular gradients controlling liver cell function, systematically defining how gene networks are dynamically modulated through intercellular communication to promote regeneration. Among other important regulators, we identified the transcriptional cofactor TBL1XR1 as a rheostat linking inflammation to Wnt/ß-catenin signaling for facilitating hepatocyte proliferation. Our data and analytical pipelines lay the foundation for future high-definition tissue-scale atlases of organ physiology and malfunction.

Design and construction of a refrigerator-cooled adiabatic calorimeter for heat capacity measurement in liquid helium temperature region.

Heat capacity is a fundamental thermodynamic property of a substance. Although heat capacity values and related thermodynamic functions are available for many materials, low-temperature heat capacity measurements, especially for novel materials, can still provide valuable insights for research in physics, chemistry, thermodynamics, and other fields. Reliable low-temperature heat capacity data are typically measured using classical adiabatic calorimeters, which use liquid helium as the refrigerant to provide a cryogenic environment for heat capacity measurements. However, liquid helium is not only expensive but also not easy to obtain, which greatly limits the application of adiabatic calorimetry. In this work, an accurate adiabatic calorimeter equipped with a Gifford-MacMahon refrigerator was designed and constructed for measuring the heat capacity of condensed matter in the temperature range from 4 to 100 K. The Gifford-MacMahon refrigerator was utilized to provide a stable liquid helium-free cryogenic environment. A simple mechanical thermal switch assembly was designed to facilitate switching between the refrigeration mode and the adiabatic measurement mode of the calorimeter. Based on the measurement results of standard reference materials, the optimized repeatability and accuracy of heat capacity measurements were determined to be within 0.8% and 1.5%, respectively. The heat capacity of α-Fe2O3 nanoparticles was also investigated with this device. Furthermore, this adiabatic calorimeter only requires electricity to operate in the liquid helium temperature range, which may significantly advance the research on low-temperature heat capacity based on adiabatic calorimetry.

Bottom-up and top-down controls on Alteromonas macleodii lead to different dissolved organic matter compositions.

The effects of both bottom-up (e.g. substrate) and top-down (e.g. viral lysis) controls on the molecular composition of dissolved organic matter have not been investigated. In this study, we investigated the dissolved organic matter composition of the model bacterium Alteromonas macleodii ATCC 27126 growing on different substrates (glucose, laminarin, extracts from a Synechococcus culture, oligotrophic seawater, and eutrophic seawater), and infected with a lytic phage. The ultra-high resolution mass spectrometry analysis showed that when growing on different substrates Alteromonas macleodii preferred to use reduced, saturated nitrogen-containing molecules (i.e. O4 formula species) and released or preserved oxidized, unsaturated sulfur-containing molecules (i.e. O7 formula species). However, when infected with the lytic phage, Alteromonas macleodii produced organic molecules with higher hydrogen saturation, and more nitrogen- or sulfur-containing molecules. Our results demonstrate that bottom-up (i.e. varying substrates) and top-down (i.e. viral lysis) controls leave different molecular fingerprints in the produced dissolved organic matter.

Potential retention of dissolved organic matter by soil minerals during wetland water-table fluctuations.

Wetlands export large amounts of dissolved organic carbon (DOC) downstream, which is sensitive to water-table fluctuations (WTFs). While numerous studies have shown that WTFs may decrease wetland DOC via enhancing DOC biodegradation, an alternative pathway, i.e., retention of dissolved organic matter (DOM) by soil minerals, remains under-investigated. Here, we conducted a water-table manipulation experiment on intact soil columns collected from three wetlands with varying contents of reactive metals and clay to examine the potential retention of DOM by soil minerals during WTFs. Using batch sorption experiments and Fourier transform ion cyclotron resonance mass spectrometry, we showed that mineral (bentonite) sorption mainly retained lignin-, aromatic- and humic-like compounds (i.e., adsorbable compounds), in contrast to the preferential removal of protein- and carbohydrate-like compounds during biodegradation. Seven cycles of WTFs significantly decreased the intensity of adsorbable compounds in DOM (by 50 ± 21% based on fluorescence spectroscopy) and DOC adsorbability (by 2-20% and 1.9-12.7 mg L-1 based on batch sorption experiment), to a comparable extent compared with biodegradable compounds (by 11-32% and 1.6-15.2 mg L-1). Furthermore, oxidation of soil ferrous iron [Fe(II)] exerted a major control on the magnitude of potential DOM retention by minerals, while WTFs increased mineral-bound lignin phenols in the Zoige soil with the highest content of lignin phenols and Fe(II). Collectively, these results suggest that DOM retention by minerals likely played an important role in DOC decrease during WTFs, especially in soils with high contents of oxidizable Fe. Our findings support the 'iron gate' mechanism of soil carbon protection by newly-formed Fe (hydr)oxides during water-table decline, and highlight an underappreciated process (mineral-DOM interaction) leading to contrasting fate (i.e., preservation) of DOC in wetlands compared to biodegradation. Mineral retention of wetland DOC hence deserves more attention under changing climate and human activities.

Uterine Commensal Peptostreptococcus Species Contribute to IDO1 Induction in Endometrial Cancer via Indoleacrylic Acid.

Microbial dysbiosis has an increasingly appreciated impact on carcinogenesis, and the cervicovaginal microbiome plays a critical role in microenvironmental inflammation. Here, we investigated the involvement of the female genital tract Peptostreptococcus species in gynecological cancer via indoleacrylic acid (IAA). IAA production from Peptostreptococcus species and the effect of bacterial culture on tumor growth in vivo were examined. The impact of IAA on cytokine production and indoleamine-2,3-dioxygenase 1 (IDO1) expression in an endometrial cancer (EC) cell line, as well as their effect on Treg and Teff cells, and M1 and M2 macrophage populations were examined in EC patients and tumor-grafted mice. Clinically, Peptostreptococcus species abundance, IAA, and IDO1 expression were verified in EC patients. The results showed that IAA production was induced in the uteri of BALB/c nude mice by Peptostreptococcus species transplantation, and the intratumoral injection of a conditioned medium from Peptostreptococcus cultures into tumor-grafted mice promoted tumor growth. IL-10 expression was upregulated by IAA; IFN-γ expression was increased by IL-10. IFN-γ induced IDO1 expression in the EC cell line. The co-culture of IDO1-expressing EC cells with peripheral blood mononuclear cells upregulated the Treg proportion and decreased the M1/M2 ratio. Clinically, P. anaerobius was more abundant amongst the uterine microbiota of EC patients than the control. The IAA, IDO1, and kynurenine/tryptophan ratios were all higher in EC tissue, and the M1/M2 ratio was lower. Our study sheds light on the link between IDO1 induction and uterine Peptostreptococcus dysbiosis and provides a potential rationale for the role of Peptostreptococcus species in immune tolerance induction in type I endometrial cancer.

A Joint State and Fault Estimation Scheme for State-Saturated System with Energy Harvesting Sensors.

In this article, the issue of joint state and fault estimation is ironed out for delayed state-saturated systems subject to energy harvesting sensors. Under the effect of energy harvesting, the sensors can harvest energy from the external environment and consume an amount of energy when transmitting measurements to the estimator. The occurrence probability of measurement loss is computed at each instant according to the probability distribution of the energy harvesting mechanism. The main objective of the addressed problem is to construct a joint state and fault estimator where the estimation error covariance is ensured in some certain sense and the estimator gain is determined to accommodate energy harvesting sensors, state saturation, as well as time delays. By virtue of a set of matrix difference equations, the derived upper bound is minimized by parameterizing the estimator gain. In addition, the performance evaluation of the designed joint estimator is conducted by analyzing the boundedness of the estimation error in the mean-squared sense. Finally, two experimental examples are employed to illustrate the feasibility of the proposed estimation scheme.

Dynamic multiple-graph spatial-temporal synchronous aggregation framework for traffic prediction in intelligent transportation systems.

Accurate traffic prediction contributes significantly to the success of intelligent transportation systems (ITS), which enables ITS to rationally deploy road resources and enhance the utilization efficiency of road networks. Improvements in prediction performance are evident by utilizing synchronized rather than stepwise components to model spatial-temporal correlations. Some existing studies have designed graph structures containing spatial and temporal attributes to achieve spatial-temporal synchronous learning. However, two challenges remain due to the intricate dynamics: (a) Accounting for the impact of external factors in spatial-temporal synchronous modeling. (b) Multiple perspectives in constructing spatial-temporal synchronous graphs. To address the mentioned limitations, a novel model named dynamic multiple-graph spatial-temporal synchronous aggregation framework (DMSTSAF) for traffic prediction is proposed. Specifically, DMSTSAF utilizes a feature augmentation module (FAM) to adaptively incorporate traffic data with external factors and generate fused features as inputs to subsequent modules. Moreover, DMSTSAF introduces diverse spatial and temporal graphs according to different spatial-temporal relationships. Based on this, two types of spatial-temporal synchronous graphs and the corresponding synchronous aggregation modules are designed to simultaneously extract hidden features from various aspects. Extensive experiments constructed on four real-world datasets indicate that our model improves by 3.68-8.54% compared to the state-of-the-art baseline.

Graph-Based Method for Calibration of High-Resolution Mass Spectra of Natural Organic Matter.

Inaccuracies in ion detection and signal processing can undermine confidence in the molecular formula assignment of high-resolution mass spectrometry, which relies on precise matching of the mass-to-charge ratio (m/z). This study proposes a novel graph-based spectra calibration method, MSCMcalib, which implements coordinate transformation and pattern detection. MSCMcalib maps uncalibrated m/z data onto a modified 2D mass defect plot, facilitating the automatic calibration of detected lines, i.e., the calibration of uncalibrated peaks aligned with these lines. The "propagation" method is subsequently employed to accurately and automatically calibrate 605 m/z values across multiple lines, encompassing 98% of the m/z range. The calibrated m/z values divide the m/z range of the spectrum into multiple subintervals, with each subinterval undergoing a process of "scaling" calibration. The utilization of narrower partitions effectively mitigates divergence issues at both ends that arise from the polynomial fitting of errors against m/z. The effectiveness of MSCMcalib is validated through the calibration of SRFA data with m/z error ranges spanning from -10 to -6 ppm, resulting in an additional assignment of 11%-30% more molecular formulas compared to the quadratic fitting calibration.

Spatiotemporal Utilization of Latent Heat in Erythritol-based Phase Change Materials as Solar Thermal Fuels.

Solar thermal fuels (STFs) have been particularly concerned as sustainable future energy due to their impressive ability to store solar energy in chemical bonds and controllably release thermal energy. However, currently studied STFs mainly focus on molecule-based materials with high photochemical activity, toxicity, and compromised features, which greatly restricts their applications in practical scenarios of solar energy utilization. Herein, we present a novel erythritol-based composite phase change material (PCM) as a new type of STFs with an outstanding capability to store solar energy as latent heat in its stable supercooling state and release thermal energy as needed. This composite PCM with stored thermal energy can be maintained stably at room temperature and subsequently release latent heat as high as 224.9 J/g during the crystallization process triggered by thermal stimuli. Remarkably, solar energy can be converted into latent heat stored in the composite PCM over months. Through mechanical stimulations, the released latent heat can increase the temperature of the composite up to 91 °C. This work presents a new concept of using spatiotemporal storage and release of latent heat in PCMs for solar energy utilization, making it a potential candidate as STFs for developing future clean energy techniques.

Seasonal sensitivity of groundwater dissolved organic matter in recognition of chronic kidney disease of unknown etiology: Optical and molecular perspectives.

Chronic kidney disease of unknown etiology (CKDu) has aroused a great concern due to its widespread prevalence in many developing countries. Dissolved organic matter (DOM) has been proved to be associated with CKDu in groundwater. However, the responses of their association to abiotic influencing factors like seasonal variation are not carefully disclosed. Herein, we revealed the seasonal variation of DOM in CKDu related groundwater (CKDu groundwater) and control group (non-CKDu groundwater) collected from Sri Lanka during the dry and wet seasons by excitation-emission matrix spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry. In both CKDu and non-CKDu groundwaters, the input of exogenous DOM during wet season improved the degree of humification and molecular weight of DOM, while oxidative processes during the dry season increased the ratios of oxygen to carbon (O/C). Furthermore, compared with non-CKDu groundwater, more DOM with high O/C enriched in CKDu groundwater during the dry season, indicating stronger oxidative processes in CKDu groundwater. It may result in the enrichment of carboxyl group and induce the enhanced leaching of CKDu-related Si and F-. The receiver operating characteristic (ROC) analysis showed that the CKDu-recognition ability of most optical and molecular indicators was susceptible to seasonal factors and their recognition abilities were stronger in the wet season. The linkage between DOM and CKDu was affected by seasonal factors through the occurrence, mobility, degradation, and toxicity of typical organic molecules (e.g., C17H18O10S). The study provides a new insight into screening pathogenic factors of other endemic diseases related to organic molecules.

Circularly Polarized Organic Light-Emitting Diodes Based on Chiral Hole Transport Enantiomers.

The circularly polarized organic light-emitting diodes (CP-OLEDs) demonstrate promising application in 3D display due to the direct generation of circularly polarized electroluminescence (CPEL). But the chiral luminescence materials face challenges as intricated synthetic route, enantiomeric separation, etc. Herein, fresh CP-OLEDs are designed based on chiral hole transport material instead of chiral emitters. A pair of hole transport enantiomers (R/S-NPACZ) exhibit intense dissymmetry factors (|gPL |) about 5.0 × 10-3 . With R/S-NPACZ as hole transport layers, CP-OLEDs are fabricated employing six achiral phosphorescence and thermally activated delayed fluorescence (TADF) materials with different wavelengths, in consistence with the generated CPEL spectra. The CP-OLEDs based on achiral red, green, and blue iridium(III) complexes exhibit external quantum efficiencies (EQEs) of 14.9%, 30.7%, and 14.1% with |gEL | factors of 8.8 × 10-4 , 2.3 × 10-3 , and 2.0 × 10-3 , respectively. Moreover, the devices using achiral blue, blueish-green, and green TADF materials display EQEs of 24.1%, 17.9%, and 25.4% with |gEL | factors of 1.0 × 10-3 , 3.6 × 10-3 , and 2.2 × 10-3 , respectively. As far as known, it is the first example of CP-OLEDs based on chiral hole transport materials, which act as the organic circularly polarizers and have potential to generate CPEL from achiral luminescence materials.

Administration of blue light in the morning and no blue-ray light in the evening improves the circadian functions of non-24-hour shift workers.

In modern 24-hour society, various round-the-clock services have entailed shift work, resulting in non-24-hour schedules. However, the extent of behavioral and physiological alterations by non-24-hour schedules remains unclear, and particularly, effective interventions to restore the circadian functions of non-24-hour shift workers are rarely explored. In this study, we investigate the effects of a simulated non-24-hour military shift work schedule on daily rhythms and sleep, and establish an intervention measure to restore the circadian functions of non-24-hour shift workers. The three stages of experiments were conducted. The stage-one experiment was to establish a comprehensive evaluation index of the circadian rhythms and sleep for all 60 participants by analyzing wristwatch-recorded physiological parameters and sleep. The stage-two experiment evaluated the effects of an intervention strategy on physiological rhythms and sleep. The stage-three experiment was to examine the participants' physiological and behavioral disturbances under the simulated non-24-hour military shift work schedule and their improvements by the optimal lighting apparatus. We found that wristwatch-recorded physiological parameters display robust rhythmicity, and the phases of systolic blood pressures and heart rates can be used as reliable estimators for the human body time. The simulated non-24-hour military shift work schedule significantly disrupts the daily rhythms of oxygen saturation levels, blood pressures, heart rates, and reduces sleep quality. Administration of blue light in the morning and no blue-ray light in the evening improves the amplitude and synchronization of daily rhythms of the non-24-hour participants. These findings demonstrate the harmful consequences of the non-24-hour shift work schedule and provide a non-invasive strategy to improve the well-being and work efficiency of the non-24-hour shift population.

Dissolved organic matter composition and characteristics during extreme flood events in the Yangtze River Estuary.

Understanding the molecular composition and fate of dissolved organic matter (DOM) during transport in estuaries is essential for gaining a comprehensive understanding of its role within the global biogeochemical cycle. In 2020, a catastrophic flood occurred in the Yangtze River basin. It is currently unknown whether differences in hydrologic conditions due to extreme flooding will significantly impact the estuarine to oceanic DOM cycle. We determined the DOM composition in the Yangtze River estuary (YRE) to the East China Sea by using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) during the high discharge and the flood period (monthly average discharge was 1.2 times higher) on the same trajectory. Our study found that the composition of DOM is more diverse, and more DOM molecules were introduced to the YRE during the flood, especially in the freshwater end member. The result revealed that the DOM was significantly labile and unstable during the flood period. A total of 1840 unique molecular formulas were identified during the flood period, most of which were CHON, CHONS, and CHOS compounds, most likely resulting from anthropogenic inputs from upstream. Only 194 of these molecules were detected in the seawater end member after transporting to the sea, suggesting that the YRE served as a 'filter' of DOM. However, the flood enhances the transport of a group of terrigenous DOM, that is resistant to photodegradation and biodegradation. As a result, YRE experienced ~1.6 times higher terrigenous DOC flux than high discharge period. Considering the increased frequency of future floods, our study provides a preliminary basis for further research on how floods affect the composition and characteristics of estuarine DOM. With the help of the FT-ICR MS technique, we can now better understand the dynamic of DOM composition and characteristics in large river estuaries.

Differences in Dissolved Organic Matter Molecular Composition along Two Plume Trajectories from the Yangtze River Estuary to the East China Sea.

Analyzing the molecular composition change of dissolved organic matter (DOM) during transportation in estuaries can enhance our understanding of the fate of DOM. However, the impact of hydrologic conditions resulting from large river plumes on the DOM cycle are less explored, and previous studies were insufficient to capture the molecular fate that occur during the transportation process. In this study, we used a range of bulk and optical techniques, as well as Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), to determine the concentration and characteristics of DOM along two trajectories of downstream plumes of diluted water of the Yangtze (Changjiang) River estuary (YRE) during the high discharge season. These two plumes situated along the route of the summer Changjiang diluted water (CDW) have been identified and named CDW-North (CDW-N) and CDW-South (CDW-S), respectively. Despite having the same riverine end-member origin, the turbidity zone in YRE significantly modifies the molecular characteristics and composition of DOM. The results of FT-ICR MS indicated a spatial variation of DOM composition in the coastal zone of the two plumes. The relative intensities of the CHO, CHOS, and CHONS compounds are negatively correlated with salinity. In addition, the coastal zones of both CDW-N and CDW-S are characterized by more autochthonous DOM sources. More CHON compounds in CDW-N are probably due to the production of autochthonous DOM in offshore waters. The activity of phytoplankton increased the surface dissolved oxygen level of CDW-N in the coastal zone. However, the hypoxic zone formed at the bottom of the CDW-N due to microbial degradation of organic matter and may further benefit the preservation of CHON compounds. Our study emphasizes that the characteristics and composition of the estuarine DOM can be significantly shaped by distinct large river plumes. Furthermore, using FT-ICR MS in combination with complementary techniques can better assist in identifying the sources and transformation mechanisms of estuarine DOM in large river plume-affected systems and provide more valuable insights into the role of DOM in the estuarine biogeochemical cycle.

Evolution of dissolved organic nitrogen chemistry during transportation to the marginal sea: Insights from nitrogen isotope and molecular composition analyses.

Estuaries are hotspots where terrestrially originated dissolved organic matter (DOM) is modified in molecular composition before entering marine environments. However, very few research has considered nitrogen (N) modifications of DOM molecules in estuaries, limiting our understanding of dissolved organic nitrogen (DON) cycling and the associated carbon cycling in estuaries. This study integrated optical, stable isotopes (δ15N and δ13C) and molecular composition (FT-ICR MS) to characterize the transformation of DOM in the Yangtze River Estuary. Both concentration of dissolved organic carbon (DOC) and DON decreased with increasing salinity, while their δ13C and δ15N increased with the increasing salinity. A significant positive correlation was found between δ15N and δ13C during the transportation of DOM to marginal seas, indicating that the behavior of both DOC and DON are primarily controlled by the mixing of freshwater and the seawater in the YRE. During the mixing process, the DON addition was observed using the conservative mixing curves. In the view of molecular composition, DOM molecules became more aromatic as the number of N atoms increased. Spearman correlations reveal that DOM molecules with fewer N atoms exhibited a higher enrichment in protein-like components, while those with more N atoms were more enriched in humic-like components. In addition, the δ15N and δ13C tended to increase as the N content of DOM decreased. Therefore, DON molecules with fewer N atoms were likely to be transformed into those with more N atoms based on the isotopic fractionation theory. This study establishes a linkage between the molecular composition and the δ15N of DOM, and discovers the N transformation pattern within DOM molecules during the transportation to marginal seas.

Fecal calprotectin: A novel predictor of ulcerated esophageal injury after atrial fibrillation catheter ablation.

BACKGROUND: Atrial esophageal fistula (AEF) is a lethal complication that can occur post atrial fibrillation (AF) ablation. Esophageal injury (EI) is likely to be the initial lesion leading to AEF. Endoscopic examination is the gold standard for a diagnosis of EI but extensive endoscopic screening is invasive and costly. This study was conducted to determine whether fecal calprotectin (Fcal), a marker of inflammation throughout the intestinal tract, may be associated with the existence of esophageal injury. METHODS: This diagnostic study was conducted in a cohort of 166 patients with symptomatic AF undergoing radiofrequency catheter ablation from May 2020 to June 2021. Fcal tests were performed 1-7 days after ablation. All patients underwent endoscopic ultrasonography 1 or 2 days after ablation. RESULTS: The levels of Fcal were significantly different between the EI and non-EI groups (404.9 µg/g (IQR 129.6-723.6) vs. 40.4 µg/g (IQR 15.0-246.2), p < .001). Analysis of ROC curves revealed that a Fcal level of 125 µg/g might be the optimal cut-off value for a diagnosis of EI, giving a 78.8% sensitivity and a 65.4% specificity. The negative predictive value of Fcal was 100% for ulcerated EI. CONCLUSIONS: The level of Fcal is associated with EI post AF catheter ablation. 125 µg/g might be the optimal cut-off value for a diagnosis of EI. Negative Fcal could predict the absence of ulcerated EI, which could be considered a precursor to AEF.

Barbier Polymerization-Induced Emission towards Fully Substituted Polyethylene Analogues with Non-Traditional Intrinsic Luminescence.

The properties of polyethylene are highly dependent on the variety and quantity of substitutions. Generally, polyethylene can only be fully substituted with fluorine atoms, mainly e. g., polytetrafluoroethylene and nafion, because atomic radius of fluorine atom is small enough. The preparation of fully substituted polyethylene analogues (FSPEA) and their non-traditional intrinsic luminescence (NTIL) are attractive, especially for substitutions with relatively larger atomic radii than a fluorine atom. Here, Barbier polymerization-induced emission (PIE) is demonstrated as a universal method for the molecular design of NTIL type FSPEAs with intriguing aggregation-induced emission (AIE) behaviors. Through Barbier polymerization of diphenyldichloromethane and different peroxyesters in the presence of Mg in one pot, a series of FSPEAs, including polytriphenylethanol (PTPE), polydiphenylfurylethanol (PDPFE), polydiphenylthiophenylethanol (PDPTE) and polydiphenylnaphthylethanol (PDPNE) have been successfully prepared. Further potential applications for explosive detection, artificial light-harvesting system and white phosphor-converted light-emitting diode are investigated. Therefore, this work opens up a new approach for the molecular design of FSPEA with non-conjugated luminescence, which may cause inspirations to different research fields like polyolefin and luminescent materials.

Understanding petroleum vapor fate and transport through high resolution analysis of two distinct vapor plumes.

No field study has provided a detailed characterization of the molecular composition and spatial distribution of a vadose zone plume of petroleum volatile organic compounds (VOCs), which is critical to improve the current understanding of petroleum VOC transport and fate. This is study reports a high-resolution analysis of two distinct vapor plumes emanating from two different light non-aqueous phase liquid (LNAPL) sources (an aliphatic-rich LNAPL for Zone #1vs an aromatic-rich LNAPL for Zone #2) at a large petrochemical site. Although deep soil vapor signatures were similar to the source zone LNAPL signatures, the composition of the shallow soil vapors reflected preferential attenuation of certain hydrocarbons over others during upward transport in the vadose zone. Between deeper and shallower soil gas samples, attenuation of aromatics was observed under all conditions, but important differences were observed in attenuation to aliphatic compound classes. Attenuation of all aliphatic compounds was observed under aerobic conditions but little attenuation of any aliphatics was observed under anoxic conditions without methane. In contrast, under methanogenic conditions, paraffins attenuated more than isoparaffins and naphthenes. These results suggest that isoparafins and naphthenes may present more of a vapor intrusion risk than benzene or other aromatic hydrocarbons commonly considered to be petroleum vapor intrusion risk drivers. While the overall vapor composition changed significantly within the vadose zone, diagnostic ratios of relatively recalcitrant alkylcyclopentanes were preserved in shallow soil vapor samples. These alkylcyclopentanes may be useful for distinguishing between petroleum vapor intrusion and other sources of petroleum VOCs detected in indoor air.

An Adaptive Two-Dimensional Voxel Terrain Mapping Method for Structured Environment.

Accurate terrain mapping information is very important for foot landing planning and motion control in foot robots. Therefore, a terrain mapping method suitable for an indoor structured environment is proposed in this paper. Firstly, by constructing a terrain mapping framework and adding the estimation of the robot's pose, the algorithm converts the distance sensor measurement results into terrain height information and maps them into the voxel grid, and effectively reducing the influence of pose uncertainty in a robot system. Secondly, the height information mapped into the voxel grid is downsampled to reduce information redundancy. Finally, a preemptive random sample consistency (preemptive RANSAC) algorithm is used to divide the plane from the height information of the environment and merge the voxel grid in the extracted plane to realize the adaptive resolution 2D voxel terrain mapping (ARVTM) in the structured environment. Experiments show that the proposed mapping algorithm reduces the error of terrain mapping by 62.7% and increases the speed of terrain mapping by 25.1%. The algorithm can effectively identify and extract plane features in a structured environment, reducing the complexity of terrain mapping information, and improving the speed of terrain mapping.