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Premature ovarian insufficiency (POI) is defined as the depletion of ovarian function before the age of 40 years. The global prevalence of POI is 3.5%. To date, genetic factors account for 23.5% of the etiology of POI. Herein, a previously uncharacterized pathogenic homozygous variant of the chromosome segregation–1–like gene (CSE1L) was identified in POI patients via targeted panel sequencing. It is reported that dysregulated iron metabolism is involved in many reproductive endocrine disorders; however, its precise role in POI remains obscure. In this study, we identified CSE1L as a potential candidate gene that plays an important role in maintaining iron homeostasis. Deficiency of CSE1L led to ferroptosis in human granulosa cells, which was confirmed by transmission electron microscopy. Mechanistically, coimmunoprecipitation identified the direct interaction between CSE1L and FoxO1. Inhibition of CSE1L led to the excessive accumulation of FoxO1 in the nucleus via nucleocytoplasmic transport. Then, FoxO1 bound to the promoter region of NCOA4 and promoted its transcription, which was verified by a chromatin immunoprecipitation assay. Moreover, inhibition of CSE1L in cumulus cell monolayer could impede oocyte maturation, which might be associated with oxidative stress. Consequently, our study first revealed that CSE1L participated in ferroptosis in human ovarian granulosa cells via nucleocytoplasmic transportation, which might be helpful in revealing the molecular mechanism of CSE1L in the development of POI. Importantly, these findings might provide new insights into the application of ferroptosis inhibitors in the treatment of POI. [ABSTRACT FROM AUTHOR]

A double flush-mounted probe method is proposed to analyze the characteristics of intermediate-pressure plasmas (10–100 Pa) by a sheath criterion. The analytical model mainly focuses on the effect of the ion drift velocity in the sheath edge and then provides a correction factor for the measured ion-collection current. The reduction of the ion current is attributed to ion–neutral collisions leading to the modified Bohm velocity. To validate this method, the ion density is calculated and compared with that measured by two types of cylindrical probes, and the results agree well with the data measured by other probes. On the basis of this work, the double flush-mounted probe can be adopted to diagnose plasma parameters accurately, without a reference electrode, in collisional and certain complex plasma environments, such as the reentry plasma sheath. [ABSTRACT FROM AUTHOR]

A new configuration of a resonant-cavity electrode microwave discharge device is developed in this work. In the device, a hollow electrode antenna is used for microwave transporting, and a well-designed resonant-cavity could enhance the absorption of the microwave power. A quartz cover is adopted to seal the vacuum and insulate the antenna from plasma, which greatly reduces the heat accumulation on the antenna. A magnetic field coil made by multiple-turn enameled wires is designed which could generate a strong magnetic field based upon a low-current power supply. In the plasma chamber, a distinctive L-shape probe is designed to measure the parameter distribution, and the two-dimensional parameters can be measured with the simple structure. In addition, the characteristic parameters such as electron density and temperature are measured in the chamber with a single probe, and the electron density distribution and spectrum are compared in argon and xenon plasma, which suggests that the microwave plasma device has good adaptability and functionality. [ABSTRACT FROM AUTHOR]

In this work, an experimental design for generation of the controllable electron density gradient is achieved through a large area oxide coated cathode and two stainless meshes. The large area oxide coated cathode is adopted to produce a large area, uniform and high density plasma, and these two metal meshes are specially designed to control the density and potential of the plasma. A boundary layer with independent electron density gradient and uniform plasma potential is subsequently generated. The controllable electron density gradient can be achieved, and the accompanied electric field can be compensated simultaneously using this design, which could be potentially extended to study the excitation of the plasma instabilities when the strong plasma density gradient exists. [ABSTRACT FROM AUTHOR]

Background: To determine the prevalence of stress urinary incontinence (SUI) and associated factors in women with premature ovarian insufficiency (POI). Materials and Methods: The study included 149 patients with POI and 303 control women without POI. Age, body mass index (BMI), gestational history, time since onset of POI, and status of hormone therapy (HT) for POI were recorded. Results: There was no statistical difference in the mean age, BMI, and parity between the two groups. The prevalence of SUI in the POI group tended to be higher than that in the control group (20.9%, 30/149 vs. 16.2%, 49/303), although not significantly (p = 0.297). About 41.6% (62/149) of patients with POI received HT. Patients with POI and SUI were older (p = 0.018) and had higher BMI (p = 0.007) than women with POI without SUI (p = 0.007). Compared to nulliparas, primiparas were more likely to have SUI (p = 0.046). However, SUI developed irrespective of time since onset of oligomenorrhea/amenorrhea or HT use. Furthermore, regression analysis showed that the prevalence of SUI was higher in women 30–39 years of age (odds ratio [OR] = 3.27, p = 0.002) and older than 40 years (OR = 7.78, p = 0.001). Primiparas (OR = 2.89, p = 0.001) and vaginal delivery (OR = 2.58, p = 0.023) were associated with SUI. Conclusions: The prevalence of SUI was fairly high among patients with POI, and age, parity, and vaginal delivery were the main risk factors. However, duration of POI and HT use had no effect on SUI. Increasing awareness of the importance of urinary system health in this population will improve the quality of life for these women. [ABSTRACT FROM AUTHOR]

The E–H-mode-transition process in an inductively coupled argon–mercury mixture discharge plasma was investigated by an interferometer and a spectrometer. The transition powers upon different natural pressures and mercury content were studied. The electron density versus input power under several discharge conditions in the E mode and H mode was measured detailedly by the interferometer. These results suggested that the nonlinear effects of power absorption and dissipation play a significant role in the mode transition process. In addition, the optical emission system was employed to obtain the intensity ratios of spectral lines at different mercury proportions, which shed light on the mechanism of stepwise ionization and the variability of H-to-E-mode-transition powers in the argon–mercury mixture discharge. [ABSTRACT FROM AUTHOR]

In the work, laboratory experiments were designed to simulate the collisional plasma environment of the ionosphere. Neutral gas was injected to increase the ion-neutral collisions, and the ambient plasma subsequently transforms from the magnetospheric-like collisionless plasma to the ionospheric-like collisional one. In the collisionless plasma, the classical electrostatic Kelvin-Helmholtz instability (KHI) was generated using an interpenetrating plasma method. However, the collisionless KHI was dissipated in the collisional plasma and subsequently a new wave mode was excited. The mode was identified as the collisional KHI by comparing the experimental results with the theoretical wave dispersion relation. The result indicates that the KHI can be excited in the ionospheric-like collisional plasma, which could be applied to understand the generation mechanism of the ionospheric irregularities by the bottomside sheared flow. [ABSTRACT FROM AUTHOR]

Abstract: Laboratory observations of spontaneous emission of Alfvénic branch oscillations generated by a strong inhomogeneous plasma flow are reported in this work. Electrostatic KH instabilities in the subcyclotron frequency range were excited using the interpenetrating plasma method. Experiments indicate that spontanegeous Alfvénic branch oscillations occur when the plasma inhomogeneity increases above a threshold. The electromagnetic wave amplitude spreads out radially over a much larger extent than the electrostatic mode. Theoretical calculations using the MHD method also support the experimental observation. The result has important application in understanding the cross‐scale transport of particles and energies in astrophysical, space, and laboratory plasmas. [ABSTRACT FROM AUTHOR]

A new approach for investigating ionosphere chemical depletion in the laboratory is introduced. Air glow discharge plasma closely resembling the ionosphere in both composition and chemical reactions is used as the artificially created ionosphere. The ionospheric depletion experiment is accomplished by releasing chemicals such as SF6, CCl2F2, and CO2 into the model discharge. The evolution of the electron density is investigated by varying the plasma pressure and input power. It is found that the negative ion (SF6-, CCl2F2-) intermediary species provide larger reduction of the electron density than the positive ion (CO2+) intermediary species. The negative ion intermediary species are also more efficient in producing ionospheric holes because of their fast reaction rates. Airglow enhancement attributed to SF6 and CO2 releases agrees well with the published data. Compared to the traditional methods, the new scheme is simpler to use, both in the release of chemicals and in the electron density measurements. It is therefore more efficient for investigating the release of chemicals in the ionosphere. [ABSTRACT FROM AUTHOR]

This study aimed to investigate different transformation mechanisms of organic nitrogen (N) fractions during composting with different raw materials, and the contributions of bacterial communities and environmental factors to organic N fractions transformation. The results showed that high molecular weight organic N was first degraded to low molecular weight organic N and then turned into NH 4 + during chicken manure composting. In comparison, organic N fractions were stored in composts rather than mineralization during garden waste and municipal solid waste composting. Meanwhile, bacterial communities, environmental factors and the combination of them were the main drivers of N transformation during chicken manure, municipal solid waste and garden waste composting, respectively. In conclusion, the proposed organic N transformation mechanisms in this study provided a theoretical basis for improving the quality of compost products. [ABSTRACT FROM AUTHOR]

In this study, hetero-two-dimensional correlation spectroscopy (hetero-2DCOS) combined with parallel factor analysis (PARAFAC) was employed to reveal the inner changes in the dissolved organic matter (DOM) components derived from soil amended with seven different composts. The dynamics of the four DOM components showed that the fluorescence peaks in each component varied in different directions during mineralization. Structural equation models (SEMs) demonstrated that the compost amendments changed the correlations of the total organic carbon (TOC), total nitrogen (TN), and bacterial community composition with DOM components and strengthened the cooperative function related to transformation of DOM components. The compost sources were further ranked as cabbage waste (CW) > chicken manure (CM), dairy cattle manure (DCM), tomato stem waste (TSW), peat (P) > municipal solid waste (MSW), sewage sludge (SS) by projection pursuit regression (PPR) analysis. It is helpful to improve the bioavailability of compost products to obtain composts with a particular function.

Humin (HM) is a complex mixture of molecules produced in the different biological processes, and the structural evolution of HM in the agricultural wastes composting are not well-known. Elucidating and comparing the structural evolution during livestock manure (LMC) and straw wastes (SWC) composting can help one to better understand the fates, features, and environmental impacts of HM. This study exploits excitation emission matrix-parallel factor (EEM-PARAFAC), two-dimensional correlation spectroscopy (2D-CoS), hetero-2DCoS, and structural equation model (SEM) to compare the fate of the HM. We fit a three-component EEM-PARAFAC model to characterize HM extracted from LMC and SWC. The results show that the HM evolution has a significant difference between LMC and SWC. As a result, the opposite change tendency and different change order of HM fluorescent components determine the different synthesis formation and evolution mechanisms. The diverse organic matter composition and dominant microbes might be the reason for the different evolution mechanism. Based on these results, a comprehensive view of the component changes of HM in the composting process is obtained. Furthermore, the superior potential of such an integrated approach during investigating the complex evolution in the environment was also demonstrated.

In this work, a double flush-mounted probe for measuring plasma parameters was designed and fabricated. The method to determine the plasma density and electron temperature using a floating double flush-mounted probe was characterized. To validate this method, the measurement results in an argon glow discharge plasma, including the electron density and temperature measurements, were compared with those obtained using a single probe and a double probe. Results indicate that the electron density measured using the double flush-mounted probe agrees well with those measured using other probes; the effective electron temperature values are also consistent within the admissible error range. These results suggest that the double flush-mounted probe can be used for accurate measurements at low pressure DC plasma discharges and also can be applied to other complex plasmas such as tokamaks, in the boundary-layer region without a reference electrode.

In this work, the design and construction of the Keda Space Plasma EXperiment (KSPEX), which aims to study the boundary layer processes of ionospheric depletions, are described in detail. The device is composed of three stainless-steel sections: two source chambers at both ends and an experimental chamber in the center. KSPEX is a steady state experimental device, in which hot filament arrays are used to produce plasmas in the two sources. A Macor-mesh design is adopted to adjust the plasma density and potential difference between the two plasmas, which creates a boundary layer with a controllable electron density gradient and inhomogeneous radial electric field. In addition, attachment chemicals can be released into the plasmas through a tailor-made needle valve which leads to the generation of negative ions plasmas. Ionospheric depletions can be modeled and simulated using KSPEX, and many micro-physical processes of the formation and evolution of an ionospheric depletion can be experimentally studied.

A comparison is made between plasma parameters measured by a flush-mounted probe (FP) and a cylindrical probe (CP) in argon glow discharge plasma. Parameters compared include the space potential, the plasma density, and the effective electron temperature. It is found that the ion density determined by the FP agrees well with the electron density determined by the CP in the quasi-neutral plasma to better than 10%. Moreover, the space potential and effective electron temperature calculated from electron energy distribution function measured by the FP is consistent with that measured by the CP over the operated discharge current and pressure ranges. These results present the FP can be used as a reliable diagnostic tool in the stable laboratory plasma and also be anticipated to be applied in other complicated plasmas, such as tokamaks, the region of boundary-layer, and so on.

The total phosphorus (TP) removal efficiency from organic wastewater (pig farm and distillery wastewater) were estimated by using filamentous green algae (FGA) and benthic algal mats (BAM) treatment systems under laboratory conditions, and the contents of periphyton phosphorus fractions were determined by using a sequential extraction. The removal rates of TP reached 59-78% within the first 8 days of all treatment systems and could achieve average 80% during 30 day period, and the phosphorus removal rates by using BAM was higher than that of FGA. The ability of retention TP of periphyton enhanced gradually, the BAM TP contents were higher than that of FGA, the highest TP concentrations of BAM and FGA were 26.24 and 10.52 mg P g(-1)·dry weight. Inorganic phosphorus (IP) always exceeded 67.5% of TP, but the organic phosphorus fraction only made up less than 20% of TP. The calcium-binding phosphorus (Ca-P) was the dominant fraction and its relative contribution to TP was more than 40%. The TP was also strongly and positively correlated with the IP and Ca-P (p < 0.01) in periphyton. It showed that the periphyton had a potential ability of rapid phosphorus removing and remarkable retention from wastewater with high load phosphorus.