Tebuconazole is a widely used fungicide that has been detected in water ecosystems, of which the concentrations may affect the endocrine function of aquatic organisms. At present study, ...tissue-specific bioaccumulation of tebuconazole was found in ovary of adult zebrafish, indicating a potential risk of endocrine disruption. In order to evaluate the potential endocrine disrupting effects, three life stages (2 hpf (hours post-fertilization) −60 dpf (days post-fertilization), Stage I; 60–120 dpf, Stage II; 180–208 dpf, Stage III) of zebrafish (Danio rerio) were chronically exposed to tebuconazole at the concentrations ranging from 0.05 mg/L to 1.84 mg/L. Result showed that exposed to tebuconazole could lead to a male-biased sex differentiation in juvenile zebrafish and significant decrease of the percentage of germ cells in sexually-mature zebrafish. Egg production was significantly inhibited by 57.8% and 19.2% after Stage II- and Stage III-exposures, respectively. The contents of 17β-estradiol in gonad decreased by 63.5% when exposed to 0.20 mg/L tebuconazole at Stage II and by 49.5% after exposed to 0.18 mg/L tebuconazole at Stage III, respectively. For all stages exposure, reductions in 17β-estradiol/testosterone ratio were observed, indicating an imbalance in steroids synthesis. Additionally, tebuconazole reduced the expression of cyp19a, which was consistent with the decrease of E2 level. In overall, the present findings indicated that, playing as an anti-estrogen-like chemical, tebuconazole inhibited the expression of Cyp19, thereby impairing steroid hormones biosynthesis, leading to a diminished fecundity of zebrafish.
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•Tebuconazole plays as an anti-estrogen endocrine disrupting effects on zebrafish.•Tebuconazole induces a male-biased gonadal differentiation in juvenile zebrafish.•Tebuconazole delays development of germ cells in puberty and adult zebrafish.•Block of E2 pathway may be the disrupting mechanism caused by tebuconazole.
Tebuconazole blocks E2 pathway, thereby leading to a male-biased differentiation in juvenile zebrafish and delaying germ cells development in puberty and adult zebrafish, playing an antiestrogen-like role.
•The technique of process mining is presented to discover bottlenecks and position deviations of gas explosion accident emergency rescue processes in underground coal mines.•The feasibility and ...advantage of extracting emergency rescue process model for GEAs from historical events log is validated and the emergency rescue process is characterized in the meantime.•The average length of cases is 23.72 events, 60% of the cases are below the average length, and 40% of the cases exceed the average length.•Considerable GEAs consume more time for emergency rescue compared with major GEAs, emergency rescue of GEAs in north part of China consumes more time compared with south part of China, the accident site of heading face is slightly higher than coal face in emergency rescue time, the emergency rescue duration is least affected by coal mine ownership; compared with case length, the factors of accident grade, coal mine region and accident site possess greater influence on case duration.•56% of the cases take less than two days, 38% of the cases take less than one day, 16% of the cases take less than half a day, while 14% of the cases take more than 10 days.•The resources of emergency rescue headquarters, barmaster and medical staff share a better centrality in GEA emergency rescue processes.
Gas explosion has always been one of the major accident types in the coal mines of China, and reliable emergency rescue process is one of the key guarantees to minimize accident losses. As an emerging discipline to discover bottlenecks and position deviations of processes, process mining is widely used to improve various business processes in recent years. Nevertheless, scarcely does any research apply it to the field of coal mine emergency rescue to our knowledge. In this study, we apply the technique of process mining to domain of gas explosion accident emergency rescue in coal mines. 50 considerable and major gas explosion accidents, which occurred from the second half of 2006–2014 in Chinese coal mines, are selected as log data. The aspects of control-flow perspective, case perspective, helicopter view, organizational dimension and performance perspective are analyzed by process mining. In terms of control-flow perspective, the emergency rescue model is extracted by the inductive miner in ProM, correspondingly, conformance checking and comparison with real-life model have shown the validity of our work. Research also shows that the average length of cases is 23.72 events, and 60% of the cases are under the average length; 56% of the gas explosion accident emergency rescue processes last less than two days; emergency rescue headquarters, barmaster and medical staff share the highest centrality in social network of rescue; the rescue performance is more affected by accident grade, compared with the factors of accident site, region of coal mine and coal mine ownership.
In this work, a novel approach that can calibrate the colors obtained with a cellphone camera was proposed for the colorimetric sensor array. The variations of ambient light conditions, imaging ...positions and even cellphone brands could all be compensated via taking the black and white backgrounds of the sensor array as references, thereby yielding accurate measurements. The proposed calibration approach was successfully applied to the detection of glucose in urine by a colorimetric sensor array. Snapshots of the glucose sensor array by a cellphone camera were calibrated by the proposed compensation method and the urine samples at different glucose concentrations were well discriminated with no confusion after a hierarchical clustering analysis.
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•The glucose in urine was detected using a colorimetric sensor array.•A calibration approach for cellphone camera imaging was proposed.•Snapshots of the glucose sensor array by a cellphone camera were calibrated.•Glucose concentrations were well discriminated with no confusion.
The responses of microbial communities in hyporheic zone to the eco-hydrological process have been a hotspot in river ecological health research. However, the impact of different metal pollution ...levels and hyporheic exchange on the microbial communities are still unclear. In this study, we further explored the effects of different degrees of heavy metals pollution and the strength of hyporheic exchange on the structures and functions of microbial community in hyporheic zone sediment ecosystem. Sediments were collected from the Weihe River to determine the concentrations of heavy metals, grain size distribution, and hydraulic conductivity, and the microbial information were obtained by eDNA technology. The comprehensive pollution status of the study area was at the slight and moderate level. The hydraulic conductivity (Kv) varied between 0.20 and 3.65 (m/d). The microbial community structures had complex temporal and spatial heterogeneity. The microbial molecular ecological network had modular characteristics and significant differences in different periods (p < 0.05). Metabolic functional genes in microbial communities had the highest relative abundance. In particular, there is a significant negative correlation between heavy metals and microorganisms (p < 0.05), with Cu and Zn contributing the most to microbial community changes (p < 0.05). Moreover, grain size had a significant impact on microorganisms, heavy metals and grain size significantly affect the predictive functions of microbial communities. Our in-depth research on microorganisms in the hyporheic zone provides references for monitoring and bioremediation of aquatic ecosystems.
•Heavy metals and grain size had significant effects on functions of microorganisms.•Heavy metal pollutants in hyporheic zone will pose certain ecological risks.•Microbial community structure and hydraulic conductivity had seasonal fluctuation.•Cu and Zn contributed the most to variations of microbial communities.•Ni, Cu, Zn and Pb had negative effects on the abundance of certain microbial taxa.
This work aims to study the surface modification and reinforcing effect in carbon fiber (CF)/nylon 12 (PA12) composites of CFs, and more importantly, resolves the practical application problems of ...modified CF/PA12 composite powder in selective laser sintering (SLS). CFs were surface modified by nitric acid (HNO3), the surface changes of CFs were characterized by SEM, FT-IR and XPS. Initially, the effects of the experimental factors on the properties of composites were investigated, and the CF/PA12 composite powder prepared with optimized technological parameters was subsequently adopted in SLS experiments. The sintering behavior and relationship between mechanical properties and porosity of sintered specimens were also discussed. The results indicated that the oxygen functional groups on HNO3 modified CFs were partly thermally decomposed and released as gas in the process of laser sintering, which caused high porosity and poor mechanical properties of sintered specimens. Treating CFs at 400°C (approximately the laser sintering temperature) after HNO3 modification was proposed as a solution. This treatment preserved part of the modified effect and reduced the porosity of the composites at the same time. Compared with the unmodified CF/PA12 sintered specimens, the tensile strength, tensile modulus, flexural strength, and flexural modulus were all increased to different degrees.
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•Modified CFs were firstly used as reinforcement phases of composites made by selective laser sintering (SLS).•The interfacial adhesion between fillers and matrix in SLS were firstly discussed.•The oxygenic groups on the surface of CFs were thermally decomposed during the sintering process.•Treating CFs at 400°C after HNO3 modification can decrease the porosity of sintered composites.•The practical application problems of modified CF/PA12 composite powder in SLS were resolved.
•In situ preparing Au nanoparticles by photoreduction in chitosan hydrogels was firstly achieved.•In situ photoreduction for creating Au nanoparticles is environmentally friendly and the operation ...procedure is very simple.•The as-prepared Au nanoparticles have good catalytic performance.•Affording an effective strategy for converting some high explosive compounds such as 2,4,6-tNT to nonexplosive.
Developing hydrogel systems featured by catalytic active is of importance to construct highly effective platforms for removing environmental pollutants/hazardous substances or for bio-/chemosensing. Reported herein are our recent finding that Au nanoparticles could be in situ prepared in chitosan-AuIII hydrogel system via photoreduction, and the as-prepared Au nanoparticles could be employed for the catalytic reduction of a series of nitroaromatic compounds by sodium borohydride (NaBH4). Experimental conditions of synthesizing Au nanoparticles, including pH, concentration of AuIII, and light irradiation time were systematically investigated. The as-prepared Au nanoparticles were characterized by UV–vis absorption spectroscopy, X-ray diffraction (XRD), transmission and field emission scanning electron microscopy (TEM and FESEM). This is the first example for in situ formed metal nanoparticles in chitosan hydrogel systems via photoreduction. The effectiveness of the as-prepared Au nanoparticles as nanocatalysts was evaluated by employing the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) by NaBH4 as a model reaction. The catalytic reduction reaction was found to be very efficient and to follow a pseudo-first-order kinetics. The as-prepared Au nanoparticles demonstrated good reusability and stability. The reduction of a series of other nitroaromatic compounds including highly explosives 2,4,6-trinitrophenol (2,4,6-tNP) and 2,4,6-trinitrotoluene (2,4,6-tNT) was achieved by means of this catalytic system.
Activity-based protein profiling (ABPP) is a technique that uses highly selective active-site targeted chemical probes to label and monitor the state of proteins. ABPP integrates the strengths of ...both chemical and biological disciplines. By utilizing chemically synthesized or modified bioactive molecules, ABPP is able to reveal complex physiological and pathological enzyme-substrate interactions at molecular and cellular levels. It is also able to provide critical information of the catalytic activity changes of enzymes, annotate new functions of enzymes, discover new substrates of enzymes, and allow real-time monitoring of the cellular location of enzymes. Based on the mechanism of probe-enzyme interaction, two types of probes that have been used in ABPP are activity-based probes (ABPs) and affinity-based probes (A
f
BPs). This review highlights the recent advances in the use of ABPs and A
f
BPs, and summarizes their design strategies (based on inhibitors and substrates) and detection approaches.
This review highlights the recent advances in the use of activity-based probes (ABPs) and affinity-based probes (A
f
BPs), and summarizes their design strategies (based on inhibitors and substrates) and detection approaches.
Stochastic competitive models with pollution and without pollution are proposed and studied. For the first system with pollution, sufficient criteria for extinction, nonpersistence in the mean, weak ...persistence in the mean, strong persistence in the mean, and stochastic permanence are established. The threshold between weak persistence in the mean and extinction for each population is obtained. It is found that stochastic disturbance is favorable for the survival of one species and is unfavorable for the survival of the other species. For the second system with pollution, sufficient conditions for extinction and weak persistence are obtained. For the model without pollution, a partial stochastic competitive exclusion principle is derived.
Polyhydoxyalkanoates (PHA) are polyesters produced by microorganisms under unbalanced growth conditions. They are generally biodegradable and thermoprocessable, making them attractive as biomaterials ...for applications in both conventional medical devices and tissue engineering. Over the past years, PHA, particularly poly 3-hydroxybutyrate (PHB), copolymers of 3-hydroxybutyrate and 3-hydroxyvalerate (PHBV), poly 4-hydroxybutyrate (P4HB), copolymers of 3-hydroxybutyrate and 3-hydroxyhexanoate (PHBHHx) and poly 3-hydroxyoctanoate (PHO) and its composites have been used to develop devices including sutures, repair devices, repair patches, slings, cardiovascular patches, orthopedic pins, adhesion barriers, stents, guided tissue repair/regeneration devices, articular cartilage repair devices, nerve guides, tendon repair devices, bone marrow scaffolds, and wound dressings. The changing PHA compositions also allow favorable mechanical properties, biocompatibility, and degradation times within desirable time frames under specific physiological conditions. This paper reviews what have been achieved in the PHA tissue engineering area and concluded that the PHA prospective will look very bright in the near future.
SIW is considered as an effective rectangular waveguide with periodically loaded vias on its two side walls instead of vertical plates. Effective wave impedances of substrate integrated waveguide ...(SIW) with varied via-to-via spacings are for the first time numerically de-embedded from three-dimensional (3-D) full-wave algorithm by virtue of a short-open-load (SOL) calibration approach. Full-wave simulation is at first conducted to model a finite-cell SIW with two feeding uniform waveguides. Afterwards, three calibration standards are formed and modeled to de-embed the two-port ABCD matrix of the finite-cell SIW section. In addition to propagation constant, effective wave impedance of the SIW can be accurately derived without any prior assumption. After numerical convergence versus unit cells is studied, these parameters are gained to give the complete view on guided-wave characteristics along the SIW.
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