Bioremediation of uranium enriched coal fly ash based on microbially induced calcite precipitation.

Coal fly ash (CFA) is an essential raw material in brickmaking industry worldwide. There are some coal mines with a relatively high content of uranium (U) in the Xinjiang region of China that are yet understudied. The CFA from these coal mines poses substantial environmental risks due to the concentrated uranium amount after coal burning. In this paper, we demonstrated a calcifying ureolytic bacterium Halomonas sp. SBC20 for its biocementation of U in CFA based on microbially induced calcite precipitation (MICP). Rectangle-shaped CFA bricks were made from CFA using bacterial cells, and an electric testing machine tested their compressive strength. U distribution pattern and immobility against rainfall runoff were carefully examined by a five-stage U sequential extraction method and a leaching column test. The microstructural changes in CFA bricks were characterized by FTIR and SEM-EDS methods. The results showed that the compressive strength of CFA bricks after being cultivated by bacterial cells increased considerably compared to control specimens. U mobility was significantly decreased in the exchangeable fraction, while the U content was markedly increased in the carbonate-bound fraction after biocementation. Much less U was released in the leaching column test after the treatment with bacterial cells. The FTIR and SEM-EDX methods confirmed the formation of carbonate precipitates and the incorporation of U into the calcite surfaces, obstructing the release of U into the surrounding environments. The technology provides an effective and economical treatment of U-contaminated CFA, which comes from coal mines with high uranium content in the Xinjiang region, even globally.

Super-exchange interaction enables Fe2-xMnxO3 perovskite with excellent catalytic oxidation activity toward hexabromocyclododecane under humidity.

Although enhancing the catalytic oxidation activity is a hotspot in thermal-driven catalytic disposal of persistent organic pollutants, few studies have managed to improve catalysts' water-resistance properties. Herein, we developed Fe2-xMnxO3 perovskite to boost the catalytic oxidation of hexabromocyclododecane under humidity by modulating its super-exchange interaction (SEI, Fe3+ + Mn3+ → Fe2+ + Mn4+). Fe0.4Mn1.6O3, with the strongest SEI, exhibits the biggest oxidation rate-constant, which is 3 times higher than that of commonly used Fe2O3 without SEI. Notably, unlike Fe2O3 which deactivates at a relative humidity of 5 %. Fe0.4Mn1.6O3 maintains its activity and is even boosted by 22 % compared to dry conditions. Mechanistic insights reveal that SEI between Fe and Mn enhances the reactivity of Mn4+- linked Olatt by lowering the reductive temperature from Mn4+ to Mn3+. Meanwhile, SEI promotes the adsorption of the associatively adsorbed H2O (HOH-type water) by reducing adsorption energy, thereby facilitating the formation of hydroxyl species, which are crucial for the oxidation process under humidity.

Straw Biochar and Graphite Oxide Enhanced External Pressure Ultrafiltration for Leaded Wastewater Treatment.

In order to solve the problem of the low treatment efficiency of wastewater containing heavy metals in mining areas, straw biochar and graphene oxide enhanced external pressure ultrafiltration (SGU) was used to treat wastewater containing high concentrations of Pb2+. The operation parameters such as pH and temperature were optimized, and the removal efficiency of CODCr, NH3-N, turbidity and Pb2+ via SGU, straw biochar ultrafiltration (SU), ultrafiltration (UF), and conventional treatment (CT) were systematically investigated. The results showed that the pH and temperature of polluted water were 4.8-5.2 and 21-30 °C, respectively, the average removal rates of CODCr, NH3-N, turbidity and Pb2+ by SGU reached 91%, 97%, 98% and 95%, respectively, and the removal effect was better than that of other processes. In addition, under the backwash conditions of clean water, weak acid, and weak alkali, the membrane flux recovered 65%, 88%, and 89% of the new membrane, respectively. This study provides scientific and theoretical support for the advanced treatment of polluted water in mining areas.

The Key Role of Cyclic Electron Flow in the Recovery of Photosynthesis in the Photobiont during Rehydration of the Lichen Cladonia stellaris.

Lichens are poikilohydric organisms and an important part of the ecosystem. They show high desiccation tolerance, but the mechanism of dehydration resistance still needs to be studied. The photosynthesis recovery of the photobiont in rehydrated lichen Cladonia stellaris after 11-year desiccation was investigated by simultaneously monitoring both photosystem I and II (PSI and PSII) activities. The responses of the photochemical efficiency and relative electron transport rate (rETR) of PSI and PSII, and the quantum yield of the cyclic electron flow (CEF) were measured using a Dual-PAM-100 system. PSI recovered rapidly, but PSII hardly recovered in C. stellaris during rehydration. The maximal photochemical efficiency of PSII (Fv/Fm) was generally very low and reached about just 0.4 during the rehydration. These results indicated that PSII had restored little and was largely inactivated during rehydration. The quantum yield of PSI recovered quickly to almost 0.9 within 4 h and remained constant at nearly 1 thereafter. The results showed that the activation of the CEF in the early stages of rehydration helped the rapid recovery of PSI. The quantum yield of the CEF made up a considerable fraction of the quantum yield of PSI during rehydration. A regulated excess energy dissipation mechanism and non-photochemical quenching (NPQ) also recovered. However, the small extent of the recovery of the NPQ was not enough to dissipate the excess energy during rehydration, which may be responsible for the weak activity of PSII during rehydration. The results indicated that both CEF and NPQ were essential during the rehydration of the photobiont in C. stellaris. The methods used in the measurements of chlorophyll a fluorescence and P700+ absorbance changes in this study provided a speedy and simple way to detect the physiological characteristics of the photobionts of lichen during rehydration. This work improves our understanding of the mechanism behind lichen's desiccation tolerance.

Feasibility Study on the Application of Biodegradable Plastic Film in Farmland Soil in Southern Xinjiang, China-Planting Tomatoes as an Example.

In recent years, polybutylene adipate-co-terephthalate (PBAT) mulch film has become one of the most commonly used biodegradable mulch films in agriculture in an attempt to combat plastic film pollution. However, its degradation characteristics and impact on the soil environment and crop growth are affected by many factors such as its composition, soil and crop types, local climate characteristics, etc. In this study, PBAT mulch film and ordinary polyethylene (PE) film were used as test materials, with non-mulching treatment (CK) as a control, to study the applicability of PBAT film in Moyu County, Southern Xinjiang region, using tomato growth as an example. The results showed that PBAT film started its induction period after 60 days, and 60.98% of the PBAT film was degraded within 100 days. Generally, the soil temperature and humidity preservation functions of this film were comparable to that of PE film in the seedling and flowering-fruiting stages of tomato growth. In the mature stage, the soil humidity under PBAT film was significantly lower than that of PE film due to its substantial degradation rate. However, this did not have any significant negative effects on tomato growth, yield, and quality. The tomato yield of 667 m2 with BPAT was insignificantly lower than that of PE film by 3.14%, and both were significantly higher than that of the CK treatment by 63.38% and 68.68%, respectively, indicating that it is feasible to use PBAT film to cultivate crops such as tomato in the arid region of Southern Xinjiang, China.

Spectral Characteristics of Dissolved Organic Matter in Farmland Soils around Urumqi, China.

The dissolved organic matter (DOM) is one of the most sensitive indicators of changes in the soil environment, and it is the most mobile and active soil component that serves as an easily available source of nutrients and energy for microbes and other living organisms. In this paper, DOM structural characteristics and main properties were investigated by three-dimensional fluorescence spectroscopy (EEM) and UV-visible spectrum technology in the farmland soils around Urumqi of China, and its possible sources and pathways were analyzed by spectroscopic indices. The results showed that humic-like substances were the main composition of the soil DOM, and its autogenesis characteristics were not obvious. Main DOM properties such as aromatability, hydrophobicity, molecular weight, molecular size, and humification degree in the southern region of Urumqi were higher than those of the northern region of Urumqi and Fukang in China, and higher on the upper layers of the soil (0-0.1 and 0.2 m) than in the deeper layer (0.2-0.3 m).This may be because the tilled layer is more subjected to fertilization and conducive to microbial activities. The spectroscopic analysis showed that the source of DOM of these regions is mainly from microbial metabolites. These results provide basic scientific data for the further research on the environmental chemical behavior of pollutants and pollution control in this region.

Distinct soil microplastic distributions under various farmland-use types around Urumqi, China.

Very little is known about the occurrence of microplastics in the soils of various land uses, especially their distributional characteristics in the soils of arid areas. In this study, 24 sampling sites across three soil layers were investigated for three different farmland-use types (greenhouses, crop fields and vegetable fields) in the main agricultural and pastoral areas around Urumqi, China. The results demonstrated that the dominant sizes of soil microplastics were 0.2-0.5 and 0.5-1.0 mm, the main shape was film (85.93 %), the main color was white, and the main polymer was polyethylene (93.1 %), indicating that most microplastics derive from the damage to residual mulches. The microplastics abundance was highest in the greenhouse plots (7763 ± 2773 items/kg), followed by the vegetable plots (4128 ± 2235 items/kg) and then the crop fields (3178 ± 3172 items/kg). No significant differences were observed among the abundances of microplastics in the 0-10 cm (1822 ± 1345 items/kg), 10-20 cm (1566 ± 1139 items/kg) and 20-30 cm (1309 ± 1028 items/kg) layers, suggesting that microplastics can migrate to the deeper soil layer and are strongly influenced by tillage disturbance. The abundance of microplastics in the north of Urumqi was found to be higher than in the south, which is closely related to the division of agricultural functional zones and the intensity of agricultural management practices. It was found that different cropping characteristics and modes of agricultural use affect the abundance and migration of microplastics in various farmland-use types, and thus their distribution. This study provides important data for follow-up research on microplastics in arid terrestrial ecosystems, and corresponding policy-making on the management of these materials.

Isolation and Degradation Characteristics of PBAT Film Degrading Bacteria.

In recent years, PBAT (polybutylene adipate-co-terephthalate) mulch has become one of the most commonly used biodegradable mulching films. In this paper, five potential strains of PBAT film degrading bacteria were screened from the soil sample using PBAT film as the sole carbon source. A highly efficient PBAT degrading strain JZ1 was isolated by comparing the degradation performance of PBAT mulching film identified as Peribacillus frigoritolerans S2313 by 16S rDNA sequence analysis. The capacity of the strain to degrade PBAT film was optimized by adjusting the cultivation conditions such as nitrogen source, pH, and inoculum volume. After 8 weeks of cultivation, the actual degradation rate of the strain to PBAT mulch film reached 12.45%. SEM (scanning electron microscopy) coupled with EDX (energy dispersive spectroscopy) analysis showed that microbial degradation is an oxidation process and is mainly due to the amorphous regions of the PBAT film. The biodegradation of PBAT film by Peribacillus frigoritolerans may provide a promising method for regulating the degradation progress of PBAT film in the farmlands.

Study on Treatment of Tiny Pollution Water with PAC-HUM System in Kuitun River.

Kuitun city, Xinjiang is dry and short of water, so it is urgent to treat and utilize all kinds of unconventional water. In view of this problem, we conducted a study on the treatment of tiny pollution water in Kuitun River. We investigated the effect of dosage of powder activated carbon (PAC) on hollow-fiber ultrafiltration membrane (HUM) performance. The results show that the stable operation time of hollow fiber ultrafiltration membranes lengthened and the rate of reduction of the flux was reduced when the PAC dosage was increased. The addition of PAC had no obvious effect on the resistance of membrane filtration. We conducted experiments to evaluate the effect of ultrafiltration of tiny pollution water in combination with PAC. When the parameters of operation and PAC dosage were appropriately regulated, the removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH3-N) and ferric ions (Fe) reached 62%, 32% and 90%, respectively. When the PAC dosage was 200 mg/L, 100 mg/L and 150 mg/L, the highest removal rates were achieved under normal temperature and pressure. The effluent COD was less than 5.0 mg/L, NH3-N was less than 1.5 mg/L and Fe was less than 0.5 mg/L, achieving better results than the quality standard of surface water (GB3838-2002). The treated water can be discharged into the river or recirculated to utilities. The fouled membrane was cleaned by water rinsing, water/acid rinsing and water/alkali rinsing, with recovery ratios of 44%, 81% and 88%, respectively. The results of this study can serve as a foundation for the efficient utilization of water resources and the development of new water treatment technologies in Xinjiang.

Removal of Polytungstate from Mine Wastewater Using a Flat Renewal Membrane Reactor with N1633 as a Carrier.

A novel flat renewal membrane reactor (FRMR) with mixed amine extractant N1633 dissolved in kerosene and NaOH solvent was studied for the removal of polytungstate [expressed as W7O246- or W (VI)] from simulated mine wastewater. FRMR contains three parts: the feeding cell, reacting cell and renewal cell. A flat membrane of polyacrylonitrile (PAN) was used in the reacting cell, which used mixed solutions of kerosene and NaOH. The amine extractant (N1633) was used as the carrier, and simulated mine wastewater containing polytungstate was used as the feeding solution. The influencing factors of the pH and the other ion strengths in the feeding solutions, the volume ratio of kerosene to NaOH solution, and the N1633 concentration in the renewal solutions were investigated in order to obtain the optimum technique parameters. It was found that the removal percentage of polytungstate could reach 92.5% in 205 min, when the concentration of the carrier (N1633) was 0.18 mol/L, the volume ratio of kerosene and NaOH in the renewal cell was 3:2, the pH in the feeding cell was 4.00, and the initial concentration of polytungstate was 3.50 × 10-4 mol/L. The stability and feasibility of FRMR were tested by the investigation of polytungstate retention and the reuse of the membrane.

The Binding Ability of Mercury (Hg) to Photosystem I and II Explained the Difference in Its Toxicity on the Two Photosystems of Chlorella pyrenoidosa.

Mercury (Hg) poses high toxicity to organisms including algae. Studies showed that the growth and photosynthesis of green algae such as Chlorella are vulnerable to Hg stress. However, the differences between the activities and tolerance of photosystem I and II (PSI and PSII) of green microalgae under Hg exposure are still little known. Responses of quantum yields and electron transport rates (ETRs) of PSI and PSII of Chlorella pyrenoidosa to 0.05−1 mg/L Hg2+ were simultaneously measured for the first time by using the Dual-PAM-100 system. The photosystems were isolated to analyze the characteristics of toxicity of Hg during the binding process. The inhibition of Hg2+ on growth and photosystems was found. PSII was more seriously affected by Hg2+ than PSI. After Hg2+ exposure, the photochemical quantum yield of PSII [Y(II)] decreased with the increase in non-photochemical fluorescence quenching [Y(NO) and Y(NPQ)]. The toxic effects of Hg on the photochemical quantum yield and ETR in PSI were lower than those of PSII. The stimulation of cyclic electron yield (CEF) was essential for the stability and protection of PSI under Hg stress and played an important role in the induction of non-photochemical quenching (NPQ). The results showed a strong combination ability of Hg ions and photosystem particles. The number of the binding sites (n) of Hg on PSII was more than that of PSI, which may explain the different toxicity of Hg on PSII and PSI.

Substantial transition to clean household energy mix in rural China.

The household energy mix has significant impacts on human health and climate, as it contributes greatly to many health- and climate-relevant air pollutants. Compared to the well-established urban energy statistical system, the rural household energy statistical system is incomplete and is often associated with high biases. Via a nationwide investigation, this study revealed high contributions to energy supply from coal and biomass fuels in the rural household energy sector, while electricity comprised ∼20%. Stacking (the use of multiple sources of energy) is significant, and the average number of energy types was 2.8 per household. Compared to 2012, the consumption of biomass and coals in 2017 decreased by 45% and 12%, respectively, while the gas consumption amount increased by 204%. Increased gas and decreased coal consumptions were mainly in cooking, while decreased biomass was in both cooking (41%) and heating (59%). The time-sharing fraction of electricity and gases (E&G) for daily cooking grew, reaching 69% in 2017, but for space heating, traditional solid fuels were still dominant, with the national average shared fraction of E&G being only 20%. The non-uniform spatial distribution and the non-linear increase in the fraction of E&G indicated challenges to achieving universal access to modern cooking energy by 2030, particularly in less-developed rural and mountainous areas. In some non-typical heating zones, the increased share of E&G for heating was significant and largely driven by income growth, but in typical heating zones, the time-sharing fraction was <5% and was not significantly increased, except in areas with policy intervention. The intervention policy not only led to dramatic increases in the clean energy fraction for heating but also accelerated the clean cooking transition. Higher income, higher education, younger age, less energy/stove stacking and smaller family size positively impacted the clean energy transition.

Cadmium Caused Different Toxicity to Photosystem I and Photosystem II of Freshwater Unicellular Algae Chlorella pyrenoidosa (Chlorophyta)

Heavy metals such as Cd pose environmental problems and threats to a variety of organisms. The effects of cadmium (Cd) on the growth and activities of photosystem I (PSI) and photosystem II (PSII) of Chlorella pyrenoidosa were studied. The growth rate of cells treated with 25 and 100 µM of Cd for longer than 48 h were significantly lower than the control, accompanying with the inhibition of photosynthesis. The result of quantum yields and electron transport rates (ETRs) in PSI and PSII showed that Cd had a more serious inhibition on PSII than on PSI. Cd decreased the efficiency of PSII to use the energy under high light with increasing Cd concentration. In contrast, the quantum yield of PSI did not show a significant difference among different Cd treatments. The activation of cyclic electron flow (CEF) and the inhibition of linear electron flow (LEF) due to Cd treatment were observed. The photochemical quantum yield of PSI and the tolerance of ETR of PSI to Cd treatments were due to the activation of CEF around PSI. The activation of CEF also played an important role in induction of non-photochemical quenching (NPQ). The binding features of Cd ions and photosystem particles showed that Cd was easier to combine with PSII than PSI, which may explain the different toxicity of Cd on PSII and PSI.

Microplastic Contamination in Urban, Farmland and Desert Environments along a Highway in Southern Xinjiang, China.

The different types of microplastics (MPs), including debris, fibers, particles, foams, films and others, have become a global environmental problem. However, there is still a lack of research and understanding of the pollution characteristics and main causes of MPs in the arid region of Xinjiang, China. In this survey, we focused on the occurrence and distribution of MPs in urban, farmland and desert areas along a highway in the survey area. Our results showed that the main types of MPs were polypropylene (PP) flakes, polyethylene (PE) films and both PE and PP fragments and fibers. The abundance levels of MPs in street dust of Korla, Alar and Hotan districts equaled 804, 307 and 1526 particles kg−1, respectively, and were positively correlated with the urban population. In farmland areas, there were only two types of MPs (films and fibers), of which the film particles dominated and accounted for 91% of the total on the average. The highest abundance rate of MPs reached 7292 particles kg−1 in the desert area along the highway. The minimum microplastic particle sizes were 51.8 ± 2.2 µm in urban street dust samples, 54.2 ± 5.3 µm in farmland soil samples and 67.8 ± 8.4 µm in samples from along the desert highway. Particle sizes < 500 µm were most common and accounted for 48−91% of the total in our survey. The abundance and shape distribution of the MPs were closely related to the different types of human activities.

Characteristics and distribution of microplastics in shoreline sediments of the Yangtze River, main tributaries and lakes in China-From upper reaches to the estuary.

Microplastics (MPs) pervade the environment and increasingly threaten both natural ecosystems and human health. In this study, we investigated MP particle concentrations in sediment samples collected from 54 sites along the banks of the Yangtze River and its major tributaries and on lakeshores. The main polymer types found in the samples were polypropylene (PP), polystyrene (PS) and polyethylene (PE). MP particle abundance in the various types of locations was 35-51,968 particles/kg dry weight (d.w.) on the banks of the main river, 52-1463 particles/kg (d.w.) on the banks of tributaries and 2574-23,685 particles/kg (d.w.) on lakeshores. Correlation between MP abundance and mean annual runoff of each upstream tributary was significant, which suggests that increased runoff brings more microplastic waste to streambank sediments. The most common shape of MP particles in all upstream samples was flake, and in downstream samples it was foam. Small microplastic particles (< 0.50 mm) were predominant at all sites in this study, and the minimum particle size in samples from the Yangtze river banks was 0.065 mm. Average abundance of MP particles on the shores of the source lake was 9069 particles/kg around the inlet but only 866 particles/kg around the outlet; the difference was due to interception associated with sedimentation and precipitation in the lake. Our study represents the large-scale study of MPs contamination in sediment along the Yangtze River and provides important data regarding the accumulation and distribution of MPs in shoreline sediments of the upper, middle and lower reaches of the Yangtze River, main tributaries and lakes in China.

Microplastics in agricultural soils: Extraction and characterization after different periods of polythene film mulching in an arid region.

Plastic film mulching has been extensively used in farmland, especially in arid regions, for over half-century. However, this has led to heavy pollution of soils by microplastics (MPs). Currently, efficient extraction of MPs from the organo-mineral soil matrix is a problem because microsize clay particles tightly adhere to MPs. It is therefore extremely challenging to investigate, identify, quantify, and characterize MP particles and their behavior in agricultural soils. In this study, we developed a simple and effective method of separating and extracting MPs from the soil matrix. Clean polyethylene (PE) MPs were obtained after a series of treatments including pressure leaching, flotation, electrostatic adsorption, and concentrated sulfuric acid (98% H2SO4) carbonization. The characteristics of MP pollutants, such as abundance, size, and morphology, in soils that have been continuously mulched with PE film for various periods of time were determined after extraction. The highest abundance of MPs (40.35 mg/kg) with sizes ranging from 0.9-2.0 mm was found in soil samples that had been continuously mulched with plastic film for 30 years. The sampled MP particles are in the microplastic size (0.8-0.3 mm) range, and the size of MPs decreases gradually as the period of mulching increased. Scanning electron microscopy analysis showed that the surface of the MP particles showed visible cracks, with round holes, and the particle surface roughened as the number of years of continuous mulching increased. Fourier-transform infrared spectroscopy results showed that the absorption peak area of hydrocarbyl (-CH2) of PE MPs decreased significantly, and the typical oxidation characteristic peak area increased as the mulching period increased. The concentration of mesoplastics also increased, from 91.20 mg/kg to 308.50 mg/kg, when the mulching period increased from 5 to 30 years.

Integration of Acoustic Liquid Handling into Quantitative Analysis of Biological Matrix Samples.

Acoustic liquid handlers deliver small volumes (nL-µL) of multiple fluid types with accuracy and dynamic viscosity profiling. They are widely used in the pharmaceutical industry with applications extending from high-throughput screening in compound management to gene expression sequencing, genomic and epigenetic assays, and cell-based assays. The capability of the Echo to transfer small volumes of multiple types of fluids could benefit bioanalysis assays by minimization of sample volume and by simplifying dilution procedures by direct dilution. In this study, we evaluated the Labcyte Echo 525 liquid handler for its ability to deliver small volumes of sample preparations in biological matrix (plasma and serum) and to assess the feasibility of integration of the Echo with three types of bioanalytical assay platforms: microplate enzyme-linked immunosorbent assay, Gyrolab immunoassay, and liquid chromatography with tandem mass spectrometry. The results demonstrated acceptable consistency of dispensed plasma samples from multiple lots and species by the Echo. Equivalent assay performance demonstrated between the Echo and manual liquid procedures indicated great potential for the integration of the Echo with the bioanalytical assay, which allows the successful implementation of microsampling strategies in drug discovery and development.

Acute toxicity of Potentilla anserina L. extract in mice.

Potentilla anserina L. is not only a medicinal plant, but also a traditional cuisine. Hence, an acute toxicity study was performed to confirm its safety profile. Forty Kunming mice were randomly divided into two groups: control group and P. anserina L. extract group. Using the maximum dosage method, the P. anserina L. extract group was given the maximum dose within 12 h, equivalent to 345.6 g/kg crude drug. The control group was given distilled water. After administration, toxicity symptoms of mice were observed, body weight and food intake were recorded. After 14 days, blood was collected to measure biochemical parameters, autopsy was carried out to observe the changes of organs, and the vital organs were separated, weighed, and preserved for histopathological examination. The results showed that P. anserina L. extract group had no toxic symptoms. The activity, weight, and diet of mice were normal, and no abnormality was found in organ index, renal function, liver function, anatomical observation, and histopathological examination. Therefore, the maximum oral dosage (345.6 g/kg) of P. anserina L. was good safety. This study indicated that P. anserina L. had a large safety range and the clinical application was safe.

[Mechanism of transcutaneous auricular vagus nerve stimulation on polycystic ovary syndrome].

Non-invasive transcutaneous auricular vagus nerve stimulation (ta-VNS) is established on the basis of auricular acupuncture and the principle of vagus nerve stimulation (VNS). The results of the comparative study of 4 indications of VNS show that ta-VNS achieves almost the equivalent effect as VNS. Moreover, the ta-VNS is advantageous at safety, economy and portability. Regarding the clinical prevention and treatment of polycystic ovary syndrome (PCOS), it is still controversial for the effect of acupuncture and moxibustion therapy including auricular acupuncture. Moreover, it is the difficulty for the principle of acupoint selection and the treatment mechanism of this therapy to be in line with modern medicine. As neuroendocrine disease, PCOS and the ovary, its target organ are all associated with the vagus nerve. It is a new idea to introduce the ta-VNS in treatment of PCOS by regulating the reproductive and endocrinal disturbance of PCOS in terms of vagus nerve and improving the acupuncture and moxibustion therapy, such as the auricular acupuncture. In the paper, the potential mechanism of the ta-VNS in treatment of PCOS is presented: 1)the ta-VNS treats PCOS by improving insulin resistance; 2)the ta-VNS relieves PCOS-induced psychological disorders through the treatment of depression; 3)the ta-VNS is applicable in treatment of PCOS complications, such as hypertension and diabetes.