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Polyethylene terephthalate (PET) is one of the most abundantly produced synthetic polyesters. The vast number of waste plastics including PET has challenged the waste management sector while also posing a serious threat to the environment due to improper littering. Recently, enzymatic PET degradation has been shown to be a viable option for a circular plastic economy, which can mitigate the plastic pollution. While protein engineering studies on specific PET degradation enzymes such as leaf-branch compost cutinase (LCC), Thermobifida sp. cutinases and Ideonella sakaiensis PETase (IsPETase) have been extensively published, other homologous PET degrading enzymes have received less attention. Ple629 is a polyester hydrolase identified from marine microbial consortium having activity on PET and the bioplastic polybutylene adipate terephthalate (PBAT). In order to explore its catalytic mechanism and improve its potential for PET hydrolysis, we solved its crystal structure in complex with a PET monomer analogue, and validated its structural and mechanistic similarity to known PET hydrolases. By structural comparisons, we identified some hot spot positions described in previous research on protein engineering of PET hydrolases. We substitute these amino acid residues in Ple629, and obtained variants with improved activity and thermo-stability. The most promising variant D226A/S279A exhibited a more than 5.5-fold improved activity on PET nanoparticles than the wild-type enzyme, suggesting its potential applicability in the biotechnological plastic recycling.

Solid particle leakage detection in double-wall pipes is industrially important, especially in chemical and petroleum engineering. Here, we developed vibration and acoustic sensor approaches for the characterization and comparative study of the applicability of leakage sand particle detection from the flow of gas pipes. A specific wideband vibration sensor and pressure-field microphone were selected to identify the vibro-acoustic characteristics within 50 kHz of the particle leakage. The vibro-acoustic time-behaviours and characteristic frequencies of particle leakage were observed by the time-frequency method. The leakage gas flow noise was verified by coherence analysis and minimized by a digital bandpass and band-elimination filter. Corresponding experiments were performed, and good agreement was found between the release pressures (0.1–0.3 MPa) with different leak sizes (0–8 mm) under different sand masses (120 μm) and vibro-acoustic Root-Mean-Square (RMS) levels. In the comparison of the two methods, the vibration method has a better frequency response for the leakage flow and is good for identifying whether there are particle leaks. The acoustic method has a time behaviour response and is good for establishing the relationship between the particle mass and signals. In addition, the acoustic method has frequency shift features with a better signal to noise ratio. The acoustic method lays the foundation for future work of more complex leakage detection combining the advantages of vibration and the acoustic method.

Objective The antibacterial activity of copper (Cu)-alloy biomaterials has shown a great potential in clinical application. Here, we evaluated the osteogenesis and antibacterial effects of Ti6Al4V-6.5wt%Cu alloy in an in vivo model of infected bone defects and determine their responsible proteins and pathways using proteomics. Methods After bone defects were filled with Ti6Al4V and Ti6Al4V-6.5wt%Cu implants for 6 week, the tissue and bone samples around the implants were harvested for radiographic, micro-CT, histological, and bone-related gene expression analyses. An iTRAQ-based protein identification/quantification approach was used to analyze the osteogenic and antibacterial effects of Ti6Al4V-6.5wt%Cu alloy. Results Imaging and histological results showed Ti6Al4V alloy induced a stronger inflammatory response than Ti6Al4V-6.5wt%Cu alloy; imaging results and osteogenic protein levels showed Ti6Al4V-6.5wt%Cu alloy exerted a stronger osteogenic effect. In vitro experiment, we found the Ti6Al4V-6.5wt%Cu had significant antibacterial effects and inhibited the activity of Staphylococcus aureus in the early stage. In addition, the bacterial biofilm formed in Ti6Al4V-6.5wt%Cu group was significantly lower than that in Ti6Al4V group. Proteomic screening of 4279 proteins resulted in 35 differentially expressed proteins for further examination which were mainly associated with the cellular process, metabolic process, stimulus response, and cellular component organization. In further exploration of the mechanism of osteogenic mineralization of Ti6Al4V-6.5wt%Cu alloy, we found out SDC4 and AGRN were the top two target proteins associated with osteogenic differentiation and bone mineralization. Conclusion Ti6Al4V-6.5wt%Cu alloy shows a great potential as a bone implant material due to its positive effects against bacterial infection and on bone formation. The Translational potential of this article At present, titanium alloys and other non-antibacterial metal materials are used in orthopedic internal fixation operations. Our study demonstrates that Ti6Al4V-6.5wt%Cu alloy has good antibacterial and osteogenic effects in vivo and in vitro. This means that Ti6Al4V-6.5wt%Cu alloy may become a new kind of antimicrobial metallic material as internal fixation material to continuously exert its antimicrobial effects and reduce the infection rate after clinical internal fixation., Graphical abstract Image 1

The evolution of vascular plants during the Devonian Period has had great impacts on terrestrial ecosystems through innovations of key characters such as leaves, heterospory, seed reproduction, and woods. Here we report a new plant, Qianshouia mira n. gen. n. sp., from the Upper Devonian Wutong (Wutung) Formation of Fanwan section, Changxing County, Zhejiang Province, China. This plant has slender axes which seldom branch. Its leaves are arranged in pseudowhorls, departing from axes with an acute angle. The leaves are strap-shaped and each can be subdivided into proximal, middle and distal portions. At the proximal portion, a middle ridge develops, and at the middle portion this ridge divides at least three times forming four to six daughter ridges, and in between are grooves. The distal portion of leaves (leaf apex) is suggested to be adaxially curved, with no ridges but with forked tips. Qianshouia probably represents a small plant with a shrubby or herbaceous habit. Due to the unique leaf morphology and the lack of fertile structures and anatomy, the exact phylogenetic position of Qianshouia is uncertain. Qianshouia might be a lycopsid in light of the pseudowhorled phyllotaxis, or alternatively, could be a sphenopsid if the dichotomous ridge system of the leaf could be demonstrated to be leaf veins. Nevertheless, Qianshouia adds to the diversity of leaf morphologies among the Late Devonian vascular plants.

The recycle split vapour (RSV) process is used for ethane recovery all over the world. However, improvements in RSV are required to treat unconventional feed gases under special conditions. In this paper, we propose three enhanced processes: RSV with propane refrigeration and pre-pressurization (RSVPP), RSV with propane and ethylene combined refrigeration (RSVPE) and RSV with propane and mixed refrigerant refrigeration (RSVPM). A comprehensive comparative analysis of the performances of these processes is carried out using conventional RSV as a reference. All the enhanced processes exhibit excellent performance in terms of the ethane recovery rate. However, the characteristics of each process cannot be differentiated using a single measure to compare the processes. The aim of this study is to evaluate the modified RSV processes in terms of economy, energy consumption and exergy. Thus, the advantages and disadvantages of each enhanced process are highlighted, enabling researchers to distinguish among the three proposed processes from different perspectives.

Marine macroalgae have gained considerable attention as renewable biomass sources. Ulvan is a water-soluble anionic polysaccharide, and its depolymerization into fermentable monosaccharides has great potential for the production of bioethanol or high-value food additives. Ulvan lyase from Alteromonas sp. (AsPL) utilizes a β-elimination mechanism to cleave the glycosidic bond between rhamnose 3-sulfate and glucuronic acid, forming an unsaturated uronic acid at the non-reducing end. AsPL was active in the temperature range of 30–50 °C and pH values ranging from 7.5 to 9.5. Furthermore, AsPL was found to be halophilic, showing high activity and stability in the presence of up to 2.5 M NaCl. The apparent Km and kcat values of AsPL are 3.19 ± 0.37 mg mL−1 and 4.19 ± 0.21 s−1, respectively. Crystal structure analysis revealed that AsPL adopts a β-propeller fold with four anti-parallel β-strands in each of the seven propeller blades. The acid residues at the protein surface and two Ca2+ coordination sites contribute to its salt tolerance. The research on ulvan lyase has potential commercial value in the utilization of algal resources for biofuel production to relieve the environmental burden of petrochemicals.

Tritium is the main component of radioactive wastewater from nuclear power plants and can be migrated into organisms to form organically bound tritium (OBT), which may pose a potential risk to aquatic ecosystem. Hence, it is essential to monitor OBT conversion in the presence of tritium exposure. In this study, the effects of pretreatment methods such as digestion on the recovery of tritium were discussed. It was found that microwave digestion pretreatment could improve the recovery of tritium by up to 90 % and allow OBT measurement with a small sample size equivalent to about 60 mg (dry weight). In addition, the efficiency of OBT transformation was different among biological samples, and the radiation hormesis phenomenon was induced by tritium exposure (3.7 × 10sup6/supBq/L) in microalgae Chlorella vulgaris（C. vulgaris）. The tritium exposure may induce radiation hormesis through the reactive oxygen species (ROS) signaling pathway, thus improving the photosynthetic capacity and metabolism level of C. vulgaris. Furthermore, enhancement of photorespiration metabolism and the antioxidation system may be important means for C. vulgaris to balance damage by tritium radiation. This study provides insights for further investigating OBT behavior, and will contribute to understanding the equilibrium damage mechanism of algae exposed to tritium.

D-Allulose, as low-calorie rare sugar, possessed several notable biological activities and was biosynthesized by D-allulose 3-epimerase (DAEase). Here, CcDAE from Clostridium cellulolyticum was successfully immobilization via covalent attachment (RI-CcDAE), and Resin-SpyCatcher/SpyTag-CcDAE modular (DI-CcDAE). Both immobilized CcDAEs exhibited higher thermal and pH stabilities than the free form, and they maintained 80.0 % of relative activity after 7 consecutive cycles and 25 days of storage. Predominantly, DI-CcDAE represented superior catalytic efficiency with a 2.4-fold increase of k

Six undescribed meleagrin analogues, isomeleagrin, meleagrin F, meleagrin G, methylmeleagrin G, isomethylmeleagrin G and meleagrin H, were isolated from the endophytic fungus Penicillium commune, which was obtained from the fresh leaves of a toxic medicinal plant, Tylophora ovata. The structures of these analogues were elucidated through extensive spectroscopic data analysis, and their absolute configurations were characterized by calculated electronic circular dichroism (ECD). Structurally, meleagrin F features an undescribed skeleton with an aniline moiety, which is linked to meleagrin through a C-C bond at C8-C26. Connecting N19-C3' through the C-N bond in meleagrin G, methylmeleagrin G, isomethylmeleagrin G and meleagrin H was rare for amino acid condensation. The cytotoxicity activity of these undescribed compounds was evaluated, and isomeleagrin exhibited a selective cytotoxicity activity against HGC27 cells with an IC

Imagery vividness is one of the key indicators to evaluate the ability to generate mental images. There is large inter-individual variability in olfactory imagery (OI) abilities, however, little is known about the underlying factors for individual OI abilities. Using a word cueing imagery paradigm and the trial-by-trial imagery vividness rating method, participants with high or low OI abilities (differentiated by the Vividness of Olfactory Imagery Questionnaire) completed two OI tasks with either shorter (2 s) or longer (8 s) image generation time. Participants' olfactory function, olfactory-related working memory and episodic recognition memory were measured using validated methods. Moreover, olfactory metacognition was assessed using the Odor Awareness Scale (OAS) and the Importance of Olfaction Questionnaire (IOQ). Compared to participants with high OI abilities, those with low OI abilities reported less vivid odor images during OI tasks. For participants with low OI abilities, the imagery vividness significantly improved as the image generation time increased. There was no difference regarding olfactory perception or olfactory-related memory performances between the high and the low OI ability groups. However, participants with higher OI abilities had significant higher scores on the OAS and the IOQ, indicating a superior olfactory-related metacognition. These results provide evidences supporting the underlying factors that related to variances of subjective ability of generating vivid odor mental images.

Sand–oil–water–gas pipe flow is common in the chemical and petroleum industries. In this paper, the identification of the solid phase in sand–oil–water–gas bubbly flow was investigated using a vibration-sensing method. Four identical high-frequency vibration sensors were selected to obtain the multiphase flow signals around the exit of a pipe elbow. Typical frequency-domain, mutual coherence, time-domain statistical, and time-domain joint analysis methods were applied for sand-vibration signal identification and characterization. Verification experiments were performed, and good agreement was found between the sand concentration (0.05–0.25 wt.%), particle size (96–180 μm) and vibrational energy in water–gas bubbly flow and oil–water–gas bubbly flow. Sand characteristic frequency bands of 14–15.39 and 15.63–16.09 kHz for water–gas bubbly flow and of 14–16.45 and 19.31–20 kHz for oil–water–gas bubbly flow were found. Sand particles were more easily identified by varying the water velocity than the gas velocity. The validity of the detected sand signals was also verified using an acoustic sensor. It was proven that the vibration-sensing method can be used to characterize solid particles in oil–water–gas bubbly multiphase flows, laying the foundation for solid identification in more complex multiphase flows.

Leakage flow carrying solid particles from a two-layer pipe system is widely encountered in the oil and gas industry. In this paper, the identification of particle-gas leakage flow from an inner pipe was developed, and leak point simulation equipment was designed. Typical statistical vibration time-behavior and time-frequency joint analyses were applied to characterize the particle leakage signal. Verification experiments were performed, and a sand particle identification frequency band from 10.2–10.95 kHz was discovered. Additionally, good agreement was found for sand particle (150 μm) identification from the leakage gas flow at different leak points (diameters from 2 to 8 mm) under different release pressures (from 0.4 to 0.8 MPa). The sand vibration energy from one leak point increased with released pressure and leak size, while for two leak points, the sand vibration energy is more sensitive to the first point and decreases with the diameter of the second point.

Intensity distribution of the X-ray beam redirected through a conventional monolithic poly-capillary quasi-parallel lens is similar to a Gaussian distribution, which will bring about unsatisfactory imaging quality for medical applications and affect the peak-to-background ratio in X-ray diffraction experiments. These disadvantages can be overcome by adopting poly-capillary X-ray lenses structured with three tiers that fabricated from different diameters of capillaries. This paper developed a mathematical model of monolithic poly-capillary quasi-parallel lens composed with different diameter tubes, and experimental data of intensity distribution, transmission efficiency and divergence have been compared with simulation results based on a ray-tracing technique.

The development of a simple, reliable and low-cost on-line particle detection method for liquid flows has been recognized as a global challenge in the chemical engineering industry. To overcome the existing limitations in the detection of sand particles in water–gas pipe flows, a non-invasive acoustic method with two special acoustic devices (installed separately on a straight pipe and a bend pipe) for the detection of miniscule sand particles was evaluated. A series of detection methods, namely, time-frequency analysis, mutual-coherence analysis, and multi-band elimination filter methods, were developed to extract weak sand features submerged in the background noise of strong flows. Verification experiments were conducted to record acoustic signals from sand-carrying flows, thereby revealing five sand characteristic frequency bands in a water–gas bubbly flow: 20.59–21.31 kHz, 24.10–24.82 kHz, 27.64–28.36 kHz, 31.10–31.84 kHz, and 34.61–35.33 kHz. Additionally, good agreement was found between the sand concentration (0.06–0.24 wt.%) with a particle size of 150 μm and the acoustic sand root mean square (RMS) level within the discovered sand frequency multi-bands, verifying the use of the proposed acoustic detection devices and the corresponding weak sand identification method. This study provides the foundation for the future detection of solids in more complex multiphase flows.

To reduce fresh water load on ships, seawater can be used for toilet flushing on-board. And saline black water was treated on-site by bioaugmentation original marine bacteria with Pseudoalteromonas sp. SCSE709-6 (P. sp. SCSE709-6) to prevent marine pollution. In the batch experiments, P. sp. SCSE709-6 was effective in nutrient removal, which was not closely related to the amount of inoculation. In the on-board continuous experiments, the systems inoculated with P. sp. SCSE709-6 possessed excellent TP removal ability (removal rate: 80.93% for T3 and 88.39% for T4). The inoculum of P. sp. SCSE709-6 changed the microbial community structure and increased the similarity of microbial communities. P. sp. SCSE709-6 had a significant influence on the performance and microbial community of the systems. This study strongly proposes that the P. sp. SCSE709-6 is a promising alternative in saline black water treatment, which has great significance to the practice of on-board seawater flushing toilet.

A dual dynamic chamber system combined with incoherent broadband cavity enhanced absorption spectroscopy (IBBCEAS) was first developed to measure nitrous acid (HONO) emission fluxes from agricultural fields in the North China Plain. The concentrations of HONO were measured with two IBBCEAS instruments in the sample and blank chambers, respectively. To ensure the accuracy and reliability of flux measurement, before the dynamic chamber system was deployed in an agricultural field, the correlation and accuracy of the two IBBCEAS instruments were tested, and the mixing uniformity of the gas in the chamber was verified. Within a week after fertilization, the observed HONO flux exhibited a pronounced diurnal variation profile with a maximum of 20.25 ng N m−2 s−1 at noontime and a minimum of −0.86 ng N m−2 s−1 in the early morning, one order of magnitude higher than the flux observed in previously reported literature from fields. During this period, the concentrations of HONO in both of the chambers was higher in the daytime than that nighttime, and the concentration of HONO in blank chamber reached the maximum of 18.88 ppbv at noon on the 5th day after fertilization. HONO and NO2 in the sample chambers showed opposite diurnal profiles. The field observation results suggested that the high HONO flux is mainly from the direct emission of soil rather than from the heterogeneous reaction of NO2. Agricultural fertilization will affect the balance of the HONO budget, and then affect the atmospheric oxidation in the North China Plain.

Conventional polycapillary X-ray lenses, which are important components of widely used X-ray optics, are very suitable for focusing or parallelling the X-rays. However, for the hexagonal arrangement of the capillary, there are some shortcomings when it is used for X-ray imaging. Although, these shortcomings can be overcome by adopting a polycapillary X-ray lens structure with a square cross-section fabricated from a square matrix array of capillaries, it is challenging to manufacture it. In this paper, we present a new type of X-ray optics: a square polycapillary slice, which is 3 mm thick. It is like a sheet and consists of 1080 × 1080 square arrayed square micro-channels. Each external wall of a square micro-channel can be approximately expressed as a paraboloid. To study its optical properties, we conducted both simulation and experimental measurements. The simulated results showed that the focal distances of the cases in which the square polycapillary slice had no fluctuations and had fluctuations were 36.7 ± 0.9 and 36.7 ± 1.8 mm, respectively. The measured focal distance was 36.6 ± 2.5 mm. The full widths of the simulated focal spot of the cases in which the square polycapillary slice had no fluctuations and had fluctuations were 621 and 657 μ m , respectively. The full width of the measured focal spot was 600 μ m . The centre area of the focal spot was star-like. Its optical properties were similar to those of the polycapillary X-ray lens. Because the micro-channels are squared arrayed, it is more suitable for X-ray imaging than conventional polycapillary X-ray lens.

Nitrous acid (HONO) is the major precursor of OH radicals in polluted areas. Accurate measurement of HONO provides vital evidence for exploring the formation of secondary pollution. Stripping coil (SC) equipped with ion chromatograph (IC) or spectrograph as one of wet chemical methods has been already used to measure HONO. The reliability of the method mainly depends on the collection efficiency and the interference from other species. In this study, a SC-IC method was set up to measure HONO. The performance of the method was assessed in the chamber using two kinds of absorption solutions i.e. ultrapure water and 25 μM Na2CO3 solution under different concentrations of SO2. Results indicated that HONO concentrations absorbed by ultrapure water and Na2CO3 solution were almost identical in the absence of SO2 in the chamber and both the collection efficiencies were >99%. However, the collection efficiency of ultrapure water decreased with the increase of SO2, indicating that the presence of SO2 resulted in the penetration of HONO. The collection efficiency kept >90% when the concentration of SO2 was no >23 ppbv. Comparing with the situation without SO2, HONO performed a remarkable increase with the presence of SO2 when using Na2CO3 absorption solution, indicating that the extra generation of HONO from the reaction between SO2 and NO2 in alkaline solution. Consequently, ultrapure water as the absorption solution could provide a high collection efficiency and avoid the interferences from SO2 when the concentration of SO2 was below 23 ppbv. High correlations (slope = 0.94–1.06, r2 > 0.90) were found during the intercomparisons between SC-IC and other three techniques, suggesting the SC-IC method developed in this study was able to measure atmospheric HONO in the field campaigns.

Rates of seed dispersal have rarely been considered important. Here, we demonstrate through field observations and experiments that rapid dispersal is essential for the unusually short-lived seeds of Aquilaria sinensis (agarwood; Thymelaeaceae), which desiccate and die within hours of exposure by fruit dehiscence in the hot, dry forest canopy in tropical southwest China. We show that three species of Vespa hornets remove most seeds within minutes of exposure. The hornets consume only the fleshy elaiosomes and deposit most seeds in damp shade, where they can germinate, a mean of 166 m from the parent tree. Electrophysiological assays and field experiments demonstrate that the hornets are attracted by highly volatile short-carbon-chain (C5-C9) compounds, including aldehydes, ketones, alcohols, and acids, emitted from the dehiscent fruit capsule. These attractive fruit volatiles share 14 of 17 major electrophysiologically active compounds with those emitted from herbivore-damaged leaves, which attract predators, including hornets. Rapid seed dispersal thus appears to have been achieved in this species by the re-purposing of a rapid indirect defense mechanism. We predict that rapid seed dispersal by various mechanisms will be more widespread than currently documented and suggest that volatile attractants are more effective in facilitating this than visual signals, which are blocked by vegetation.

Opacity interferes with the direct observation of the demulsification of heavy oil emulsions promoted by sand particles. According to measurements of asphaltene adsorbed on the surface of mineral particles (quartz and alginate) by Fourier transform infrared spectroscopy (FTIR), some academics speculated that these particles adsorb asphaltene on an oil/water interfacial film, which destroys the strength of the oil/water interfacial film and promotes the coalescence and settling of water droplets, thus achieving demulsification and delamination. However, this mechanism cannot explain some of the phenomena observed in our experiments. In this study, bottle experiments, rheology tests, and wettability tests were carried out, the results were combined with van Oss theory and liquid bridge theory, and the mechanism by which sand promotes the demulsification of heavy oil emulsions was identified. The polar component of the surface energy of water is much greater than that of oils; as a result, water has better immersion wetting effect on quartz than oils, causing water to preferentially wet sand particles. When sand particles are small, and water droplets are large, the droplets completely wet and encapsulate the sand particles. When this occurs, the specific gravity of water droplets encapsulating sand particles increases and the settling speed of the water droplets is accelerated. This is the main reason why sand particles promote demulsification of heavy oil emulsions, which has been verified in this study by sand deposition experiments in white oil.

NO3 radicals can clean the atmospheric primary contaminants during the night. However, it can also effect the formation of secondary organic aerosol (SOA) and nitrate, which may worsen air quality. We report field observations of NO3 radicals with a home-made long path differential optical absorption spectroscopy (LP-DOAS) at a rural site in the polluted North China Plain in the summer of 2014. The detection limit (1σ) of NO3 with 3.4 km optical path was 3.4 ppt. The observed mean NO3 mixing ratios were 21 ppt with the maximum value of 104 ppt. The average calculated production rates and steady state lifetime of NO3 were 952 ppt/h and 103 s, respectively. The increase of both PM2.5 (>60 μg/m3) and RH (>60%) would result in an increase of the loss of NO3. The proportion of indirect losses rise with the increase of RH (>50%). The fitting kNO3 ranged from 0.0018 to 0.012 s−1 while γN2O5 was 0.0012 to 0.072. The ratios of direct loss ranged from 20.95% to 90.36% with an average of 56.81% during the campaign.

Lithological recognition is of great significance in oil drilling fields. To investigate the relationship between rock properties and the vibro-acoustic signal characteristics generated by drilling, a rock drilling vibration measurement system has been developed, and a relative drilling test is conducted indoors. This paper illustrates the application of a vibration sensor and a special wideband acoustic sensor method to distinguish the specific time–frequency characteristics generated by drilling in different types of rock. Furthermore, an intuitive comparison of these two approaches is performed. In particular, an acoustic focusing device was designed to assist the wideband acoustic condenser microphone in detecting specific signals during the drilling process. In addition, time-domain and time–frequency analyses were proposed to reveal the differences in signal characteristics generated by different kinds of rock. The results indicate that both the vibration spectral characteristics and the acoustic spectral characteristics from 4 types of rock show significant differences, which may be promising for lithological recognition using the feature model. However, the acoustic sensor approach, benefiting from the specially designed acoustic focusing device, presents a better signal-to-noise ratio than the vibration sensor approach.

Plant rhizomes and roots occur in terrestrial ecosystems since at least the Devonian, but the documentation of belowground plant tissues is sparse in the fossil record. In this study, fossils representing belowground rhizomes and roots are described from the top of the Upper Yaopo Formation (Middle Jurassic), at the Yuejiapo section, Mentougou District, Beijing, China. Morphological studies of the plant fossils, together with lithofacies analyses, provide new information on plant–soil interactions during the Jurassic period. Three types of rooting systems are recognized from two fossiliferous beds. The Bed-1 Flora is interpreted as representing a Cladophlebis-dominated community, where abundant foliage remains mainly of Cladophlebis cf. scariosa and Cladophlebis delicatula are associated with Type-A rooting system. The Bed-2 Flora includes Type-B and Type-C rooting systems, although the floristic composition is unknown due to the absence of identifiable foliage remains. The Type-A and Type-B rooting systems consist of abundant in situ vertical rhizomes, fine shoot-borne roots and lateral roots, and are consistent with those of some extant ferns. The Type-C rooting system shows a thick central taproot and at least three orders of lateral roots, an architecture typical of various gymnosperms. The in situ rooting systems, as well as sedimentary evidence, contribute to the recognition of stacked, reworked Entisols in a dynamic waterlogged environment.

Hydroxy amino acids are produced by Fe(II)/αKG-dependent dioxygenases and used widely as medicinal intermediates for chemical synthesis. A novel l -leucine 5-hydroxylase gene from Nostoc piscinale (NpLDO) was cloned into pET28a (+), pColdI and pQE-80 L plasmids. Using a two-step purification process (Ni-affinity chromatography and gel filtration), highly purified recombinant NpLDO was obtained. Recombinant NpLDO displayed unexpectedly high sulfoxidation activity toward l -methionine. The reaction products were analyzed by high-performance liquid chromatography. Sequence alignment analysis implied that residues of His150, His236 and Asp152 constitute the catalytic triad of NpLDO, which is completely conserved in the Fe(II)/αKG-dependent dioxygenase superfamily. Biochemical data showed that NpLDO catalyzed regio- and stereoselective hydroxylation of l -leucine and sulfoxidation of l -methionine with Fe(II) and l -ascorbic acid as cofactor, and αKG as cosubstrate, respectively.

Yangtze River Delta (YRD) area is one of the important economic zones in China. However, this area faces increasing environmental problems. In this study, we use ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) network in Eastern China to retrieve variations of NO2, SO2, and formaldehyde (HCHO) in the YRD area. Three cities of YRD (Hefei, Nanjing, and Shanghai) were selected for long-term observations. This paper presents technical performance and characteristics of instruments, their distribution in YRD, and results of vertical column densities (VCDs) and profiles of NO2, SO2, and HCHO. Average diurnal variations of tropospheric NO2 and SO2 in different seasons over the three stations yielded minimum values at noon or in the early afternoon, whereas tropospheric HCHO reached the maximum during midday hours. Slight reduction of the pollutants in weekends occurred in all the three sites. In general trace gas concentrations gradually reduced from Shanghai to Hefei. Tropospheric VCDs of NO2, SO2, and HCHO were compared with those from Ozone Monitoring Instrument (OMI) satellite observations, resulting in R2 of 0.606, 0.5432, and 0.5566, respectively. According to analysis of regional transports of pollutants, pollution process happened in YRD under the north wind with the pollution dissipating in the southeast wind. The feature is significant in exploring transport of tropospheric trace gas pollution in YRD, and provides basis for satellite and model validation.

Excessive release of phosphorus (P) from wastewater into water systems is a significant environmental problem. Aerobic P removal, a new P removal pathway, was investigated. P removal primary mechanisms of marine bacteria Shewanella sp. CF8-6 (S. sp. CF8-6) were studied by batch tests and characterization analysis. The strain showed wide environmental adaptability (temperature 5.0–35.0 °C, dissolved oxygen (DO) 5.2–8.6 mg/L, pH 5.8–9.6, salinity 0.0–10.0%, P concentration 1.1–11.7 mg/L and COD/N (C/N) 7–13) and a relatively high P removal performance under strict aerobic conditions. The optimum conditions of P removal by S. sp. CF8-6 was: temperature 25.0 °C, DO 7.83 mg/L, pH 7.2, salinity 5.0%, P concentration 11.74 mg/L and C/N 13. The higher P removal rate was associated with better biomass growth of S. sp. CF8-6 in general, but the strategy of biomass-independent P removal was also indicated. Only a small percentage (20.0%) of removed P contributed by bacterial growth and intracellular metabolism, while a considerable part (up to 60%) was reserved in extracellular polymeric substances (EPS) in the form of extracellular phospholipid nanoparticles. The scanning electron microscope-energy dispersive spectrometer (SEM-EDS) results indicated the element in the accumulation nanoparticles was carbon, oxygen, sodium and P. The 31P nuclear magnetic resonance (NMR) analysis illustrated that orthophosphate monoester was the only intracellular P species, while both orthophosphate monoester and diesters existed extracellularly. Batch treatment of actual wastewater showed S. sp. CF8-6 had application potential in saline wastewater treatment. This study introduced a new pathway of P accumulation and removal. Application of marine bacteria S. sp. CF8-6 provided us an alternative method for P removal, especially in saline wastewater.

Conventional polycapillary X-ray lenses are fabricated using an arrangement of hollow cylindrical tubes (i.e., capillaries) in a hexagonal structure, which necessarily includes triangular-shaped non-functional spaces between the capillaries. These non-functional spaces reduce the transmission efficiency of the lens, and can also affect the utilization of the pixels of charge-coupled devices in imaging applications. These disadvantages can be overcome by adopting a polycapillary X-ray lens structure with a square cross-section fabricated from a square matrix array of capillaries, each with equivalent square cross-sections. We develop a mathematical model of a square poly-capillary X-ray lens, and also present a simulation-driven numerical method for calculating the X-ray transmission efficiency, intensity distribution of the exit plane and the focal spot based on a ray-tracing technique.

In this paper, we present the development and evaluation of a new designed light emitting diodes (LEDs) based optical fiber coupling long-path differential optical absorption spectroscopy (LP-DOAS) instrument for atmospheric SO2, O3 and NO2 detections. The strongest absorption structures of these trace gases scattered along a wide spectral range which could not be covered by a single LED. Therefore, a new fiber optic coupling telescope was developed to combine multiple LEDs with different spectral emission ranges as broad band light source for atmospheric trace gas detections. Details of the experimental setup, measurement and retrieval procedure, error analysis and the atmospheric measurement results are presented. The new LED LP-DOAS measurement results show perfect agreements with a co-located Xenon Lamp coaxial LP-DOAS observations with Pearson correlation coefficient (R) larger than 0.9 for SO2, O3 and NO2 observations. The estimated background light contributes about 3–10% of the total measurement error during daytime, which is improved by a factor of 3–10 compared to previous study. Diurnal analysis of the measurement results shows a similar diurnal pattern of NO2 and SO2 which implies that they are probably originated from similar emission sources. Satellite observation and backward trajectories analysis indicated local and regional transports of pollutants have significant impacts on the air quality in Hefei. Analysis of the wind speed and wind direction show that elevated NO2 and SO2 levels were related to the emissions of the power plant and factories located at the east and northeast of the measurement site.

Studies of the human skin microbiome suggest that Propionibacterium acnes strains may contribute differently to skin health and disease. However, the immune phenotype and functions of T helper type 17 (Th17) cells induced by healthy (PH) versus acne (PA) skin-associated P. acnes strains are currently unknown. We stimulated peripheral blood mononuclear cells from healthy donors and observed that PA strains induce higher IL-17 levels than PH strains. We next generated PH and PA strain-specific Th17 clones and show that P. acnes strains induce Th17 cells of varied phenotype and function that are stable in the presence of IL-2 and IL-23. Although PH- and PA-specific clones expressed similar levels of LL-37 and DEFB4, only PH-specific clones secreted molecules sufficient to kill P. acnes. Furthermore, electron microscopic studies showed that supernatants derived from activated PH and not PA-specific clones exhibited robust bactericidal activity against P. acnes, and complete breaches in the bacterial cell envelope were observed. This antimicrobial activity was independent of IL-26, because both natural IL-26 released by Th17 clones and rhIL-26 lacked antimicrobial potency against P. acnes. Overall, our data suggest that P. acnes strains may differentially modulate the CD4+ T-cell responses, leading to the generation of Th17 cells that may contribute to either homeostasis or acne pathogenesis.

Antimonselite (Sb2Se3) bulk material has been prepared by mechanical alloying through ball milling of the elemental precursors antimony (Sb) and selenium (Se) in place of conventional solid state synthesis. X-ray diffraction (XRD), Raman spectroscopy studies and Energy dispersive spectroscopy (EDS) studies confirm the formation of polycrystalline Sb2Se3 along with elemental Sb. The as-milled bulk material was used as source to deposit Sb2Se3 thin films by e-beam deposition. Thin films have been grown at a substrate temperature of ∼373 K with an optimal electron beam current (Ib) of ∼30 mA at fixed voltage of ∼5 kV. The films were studied using XRD and Raman spectroscopy for the structural and phase analyses. Scanning electron microscopy (SEM) studies and energy dispersive spectroscopy (EDS) measurements revealed the formation of near stoichiometric thin films with smooth and uniform surface. Rutherford backscattered spectrometry (RBS) and proton induced X-ray emission spectroscopy (PIXE) tools were employed to confirm the chemical composition of as-grown Sb2Se3 thin films. Optical transmission spectrum showed a very sharp transition near the fundamental absorption edge ∼1.26 eV. The films exhibited an average absorption coefficient values exceeding > 104 cm−1 in the visible region making it a promising material for solar absorber in thin film solar cell.