Dual Phases of Respiration Chain Defect-Augmented mROS-Mediated mCa 2+

Mitochondrial respiratory chain (RC) deficits, resulting in augmented mitochondrial ROS (mROS) generation, underlie pathogenesis of astrocytes. However, mtDNA-depleted cells (ρ0) lacking RC have been reported to be either sensitive or resistant to apoptosis. In this study, we sought to determine the effects of RC-enhanced mitochondrial stress following oxidative insult. Using noninvasive fluorescence probe-coupled laser scanning imaging microscopy, the ability to resist oxidative stress and levels of mROS formation and mitochondrial calcium (mCa2+) were compared between two different astrocyte cell lines, control and ρ0 astrocytes, over time upon oxidative stress. Our results showed that the cytoplasmic membrane becomes permeated with YO-PRO-1 dye at 150 and 130 minutes in RBA-1 and ρ0 astrocytes, respectively. In contrast to RBA-1, 30 minutes after 20 mM H2O2 exposure, ρ0 astrocytes formed marked plasma membrane blebs, lost the ability to retain Mito-R, and showed condensation of nuclei. Importantly, H2O2-induced ROS and accompanied mCa2+ elevation in control showed higher levels than ρ0 at early time point but vice versa at late time point. Our findings underscore dual phase of RC-defective cells harboring less mitochondrial stress due to low RC activity during short-term oxidative stress but augmented mROS-mediated mCa2+ stress during severe oxidative insult

Forest Soil Heterogeneity and Soil Sampling Protocols on Limestone Outctops: Example from SW China

Forest soil heterogeneity of outcrop karst was studied by testing soil organic carbon at a selected 20 m × 30 m plot set up in Maolan primitive karst forest area, southern Guizhou Province, China. 90 microhabitats in the plot are roughly classified into 7 distinct microhabitat There was great heterogeneity in the plot not only for soil distribution but for great difference of soil organic carbon content. Soil organic carbon (SOC) contents were much higher, ranging from 40.1 g/kg to 203.5 g/kg. The CV (coefficient of variation) value of SOC from 38 soil sampling points, 22 sampling microhabitats, each microhabitat type, and individual microhabitat was 43%, 41%, 2.2% to 42%, 14% to 57.3% respectively. This showed high soil heterogeneity in terms of soil distributing pattern, size and soil organic carbon SOC content in outcropped karst. Different methods were applied to calculate SOC content in the plot. Small discrepancies suggested that the mixed soil samples collected from the major microhabitat types covering 95% soil distributing area were capable of representing soil nutrient status of the whole plot

The relationship between dominant follicle development and clinical outcomes of hormone replacement therapy-frozen embryo transfer: a retrospective clinical study

Research questionHormone replacement therapy (HRT) is one of the most used endometrial preparation protocols for frozen embryo transfer (FET) due to the convenience of its administration and stability of pregnancy outcomes. There are several HRT cycles accompanied by the development of dominant follicles. However, the relationship between dominant follicle development and clinical outcomes in HRT-FET cycles remains unclear.DesignWe carried out a retrospective cohort study of 13251 cycles at our reproductive medicine center from 2012 to 2019. Total cycles were divided into two groups according to whether there was dominant follicular development. In addition, we conducted a secondary analysis that used propensity-score matching to reduce confounding variables. A univariate and multivariable logistic regression model was further employed to analyze the effect of dominant follicle development in HRT cycles on clinical pregnancy outcomes.ResultsThere was no significant correlation between dominant follicle development in HRT-FET cycles and the clinical pregnancy rate (adjusted OR = 1.162, 95% CI: 0.737-1.832, P = 0.52). In addition, there was a positive correlation between the basic follicle-stimulating hormone (FSH) level and the development of dominant follicles, while there was a negative correlation between antral follicle count (AFC), menstrual cycle length and the development of dominant follicles in HRT cycles.ConclusionsThe development of dominant follicles in HRT-FET cycles does not affect the clinical pregnancy rate, early miscarriage rate and live birth rate. Therefore, it is not necessary to immediately cancel the FET cycle immediately when dominant follicle development is monitored in the HRT-FET cycle

2-Amino-4-tert-butyl-5-(2,4-dichloro­benz­yl)thia­zol-3-ium bromide

The asymmetric unit of the title compound, C14H17Cl2N2S+·Br−, contains one cation and two Br− ions with site symmetry . The dihedral angle between the planes of the thia­zol and the dichloro­phenyl rings is 77.8 (6)°. In the crystal, the ions are connected by N–H⋯Br hydrogen bonds

Open circuit voltage and state of charge relationship functional optimization for the working state monitoring of the aerial lithium-ion battery pack.

The aerial lithium-ion battery pack works differently from the usual battery packs, the working characteristic of which is intermittent supplement charge and instantaneous large current discharge. An adaptive state of charge estimation method combined with the output voltage tracking strategy is proposed by using the reduced particle - unscented Kalman filter, which is based on the reaction mechanism and experimental characteristic analysis. The improved splice equivalent circuit model is constructed together with its state-space description, in which the operating characteristics can be obtained. The relationship function between the open circuit voltage and the state of charge is analyzed and especially optimized. The feasibility and accuracy characteristics are tested by using the aerial lithium-ion battery pack experimental samples with seven series-connected battery cells. Experimental results show that the state of charge estimation error is less than 2.00%. The proposed method achieves the state of charge estimation accurately for the aerial lithium-ion battery pack, which provides a core avenue for its high-power supply security

Species-specific and needle age-related responses of photosynthesis in two Pinus species to long-term exposure to elevated CO2 concentration

There is, so far, no common conclusion about photosynthetic responses of trees to long-term exposure to elevated CO2. Photosynthesis and specific leaf area (SLA) of 1-year-old and current-year needles in Pinus koraiensis and P. sylvestriformis grown in open-top chambers were measured monthly for consecutive two growing seasons (2006, 2007) after 8-9years of CO2 enrichment in northeastern China, to better understand species-specific and needle age-related responses to elevated CO2 (500μmolmol−1CO2). The light-saturated photosynthetic rates (P Nsat) increased in both species at elevated CO2, but the stimulation magnitude varied with species and needle age. Photosynthetic acclimation to elevated CO2, in terms of reduced V cmax (maximum carboxylation rate) and J max (maximum electron transport rate), was found in P. koraiensis but not in P. sylvestriformis. The photosynthetic parameters (V cmax, J max, P Nsat) measured in different-aged needles within each species responded to elevated CO2 similarly, but elevated CO2 resulted in much pronounced variations of those parameters in current-year needles than in 1-year-old needles within each species. This result indicated that needle age affects the magnitude but not the patterns of photosynthetic responses to long-term CO2 enrichment. The present study indicated that different species associated with different physioecological properties responded to elevated CO2 differently. As global change and CO2 enrichment is more or less a gradual rather than an abrupt process, long-term global change experiments with different plant species are still needed to character and better predict the global change effects on terrestrial ecosystem