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Quercus rehderiana Hand.-Mazz. belongs to Quercus sect. Heteroallenes' of the Fagaceae family. It is widely distributed in forests with rocky and non-rocky desertification in Guizhou Province of Southwest China. However, our knowledge of the adaptation strategies of Quercus in forests with rocky desertification is surprisingly lacking. In this study, 16 leaf traits (morphological, anatomical, and chemical) of Quercus rehderiana were investigated in 15 individuals in five 20 × 20 m quadrants of forests with rocky and non-rocky desertification. The aim was to analyze their strategies of adaptation to arid and poor-soil environments in forests with rocky desertification. The results showed that Quercus rehderiana leaves in forests with rocky desertification had a greater leaf thickness, specific leaf area, abaxial epidermis thickness, and sponge mesophyll thickness but a lower leaf area than in forests with non-rocky desertification. Quercus rehderiana leaves in forests with rocky desertification had higher calcium and magnesium concentrations and a higher N:P ratio but lower potassium and phosphorus concentrations than in forests with non-rocky desertification. The results of principal component analysis showed that forests with rocky desertification tended to show resource-conserving strategies with thicker leaf tissue and a lower nutrient concentration, while forests with non-rocky desertification tended to show resource acquisition strategies with a greater leaf area and potassium concentration. In resource-poor environments, species that adopt conservative resource strategies are more likely to survive; therefore, we forecasted that more conservative, slow-growing Quercus rehderiana will be more stable over time. [ABSTRACT FROM AUTHOR]

Rocky desertification (RD), a natural and human-induced process of land degradation in karst areas, has become the primary ecological disaster and one of the obstacles to sustainable ecological development in southwest China. Nevertheless, the variation of soil physical and chemical properties, bacterial and fungal communities, and their relationships in RD forests remains limited. Therefore, soil samples were collected from forests under four degrees of RD (NRD, non-RD; LRD, light RD; MRD, moderate RD; and SRD, severe RD) and subjected to high-throughput sequencing of 16S rRNA and ITS1 genes. The results showed a significant reduction in bacterial richness and diversity, while fungal richness and diversity decreased markedly and then showed a balanced trend with the increase in RD degree, indicating that bacteria and fungi did not present the same dynamics in response to the process of RD. The bacterial communities were dominated by Proteobacteria, Actinobacteria, Acidobacteria, and Chloroflexi, while the fungal communities were dominated by Basidiomycota, Ascomycota, and Mortierellomycota. The PCoA and NMDS demonstrated significant differences in microbial communities in study sites, among which the fungal communities in non-RD forest and LRD forest clustered together, suggesting that fungal communities were more stable than bacteria in RD forest. The db-RDA, Mantel test, and random forest model confirmed the important role of soil BD, pH, SOC, AN, and AP in driving microbial diversity and communities. The IndVal analysis suggested that Chloroflexi, Patescibacteria, Atheliales, and Cantharellales with high indicator values were identified as potential bio-indicators for RD forests. This study could not only improve our understanding of bacterial and fungal community dynamics across RD gradients, but also could provide useful information for the further use of microorganisms as indicators to reflect the environmental changes and ecosystem status during forest RD. [ABSTRACT FROM AUTHOR]

Infrared transparent Ce‐doped Y3Fe5O12 (Ce: YIG, CexY3‐xFe5O12, x = 0, 0.12, 0.24, 0.36) ceramics were successfully produced by the solid‐state reaction using a hot‐press sintering process from the Y2O3, Fe2O3, and CeO2 powders. The phase structure, microstructure, infrared transmittance, and magnetic and magneto‐optical properties of the Ce‐doped Y3Fe5O12 ceramics were measured and analyzed. The in‐line transmittances of the Ce‐doped Y3Fe5O12 ceramics with the x = 0, 0.12, 0.24 (L = 0.5 mm) at 1550 nm were about 72%, 66.5%, and 57.6%, respectively. In the state of saturation magnetization, the Faraday rotation angle per centimeter (θF) of CexY3‐xFe5O12 (x = 0, 0.12, 0.24) ceramics measured by the light extinction method was 182.5, −410.4, and −958.3 deg./cm, respectively. The change of the θF was about −142.5 deg./cm when per 1at.% Ce was substituted in the dodecahedral site of YIG materials. The (Ce0.24Y2.76)Fe5O12 ceramics were determined as the optimized composition for its excellent infrared optical and magneto‐optical properties. [ABSTRACT FROM AUTHOR]

In this study, the porous Mn2O3/TiO2 microspheres were prepared via a facile two-step hydrothermal method. Firstly, the Mn2O3 particles were obtained by the calcination of hydrothermal-synthesized MnCO3. Then the TiO2 layer was coated on the surface of the Mn2O3 particles by a hydrothermal-assisted liquid phase deposition (HA-LPD) method. The as-prepared samples were analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscope (TEM) and Brunauer-Emmett-Teller analyzer (BET), respectively. Moreover, the electrochemical performances of Mn2O3/TiO2 as an anode material in lithium ion batteries (LIBs) were also evaluated. The results indicated that, the specific capability of the Mn2O3/TiO2 composite material was about 452 mAh g−1 at the current density of 500 mA g−1 after 200 cycles, which was much higher than that of pristine Mn2O3 (313 mAh g−1). Meanwhile, the rate capacity of Mn2O3/TiO2 was 177 mAh g−1 at the current density of 4 A g−1, which was also higher than that of pure Mn2O3 (3 mAh g−1). Moreover, the Mn2O3/TiO2 composite material can still yield a specific capacity of 800 mAh g− 1 at the current density of 1 A g−1 after 1000 cycles. The enhanced electrochemical performances of Mn2O3/TiO2 composite material was mainly attributed to the synergistic effect between the Mn2O3 with high capacity and TiO2 with superior stability. [ABSTRACT FROM AUTHOR]

Objective: To compare the clinic value between the transcervical resection of myoma (TCRM) and laparoscopic myomectomy (LM), and investigate the favourable surgical approaches in women with intramural uterine myomas. Methods: From January 1, 2007 to December 31, 2011, 236 women undergoing TCRM (hysteroscopy group) and 392 women undergoing LM (laparoscope group) were studied retrospectively in The Third Affiliated Hospital of Zhengzhou University. The patients' general information, peri -operative characteristics, postoperative muscle healing, and pregnancy outcome were compared and analyzed. Results: The average operation time, the average intraoperative blood loss and the reduce perioperative hemoglobin level of hysteroscopic group and laparoscopic group were compared respectively, the difference had statistical significance (P <0.05). The transfer laparotomy operation rate, postoperative fever rate and menstrual period rate of hysteroscopic group and laparoscopic group were compared. There was no significant difference (P>0.05). In the follow-up of 181 cases of hysteroscopy group and 336 cases of laparoscopic group of patients, the muscular complete healing rate of postoperative 1 month, 3 months, 6 months were respectively comparison, the difference had statistical significance (P<0.05). The muscular complete healing rate of postoperative 12 months was no statistically significant difference (P=0.709). The postoperative pregnancy from fibroids weed out of time for the first time of hysteroscopic group and laparoscopic group was statistically significant difference (P<0.05). All patients with postoperative pregnancy appeared no pregnant uterine rupture. Conclusions: For intramural myoma, two kinds of operation modes are safe and reliable. The intraoperative bleeding and postoperative recovery by TCRM is better than the patientes treated by LM, so hysteroscopy surgery is superior to the laparoscopic surgery for the patients with intramural uterine myoma. [ABSTRACT FROM AUTHOR]

Anions are ubiquitously distributed not only in biological systems but also in environment. Accordingly, anion recognition and sensing have attracted increasing attention due to the important roles anion plays in biological, chemical and environmental fields. Among various anionic species, NO3- is a very important inorganic anions which has a great harm to the environment and human health. At present, methods for the determination of NO3- mainly contained electrochemical method, ion chromatography and ion selective electrode method. Although all methods have their own advantages, but also has the obvious deficiency. Such as, the reproducibility of electrochemical method is not good, and ion chromatography and ion selective electrode method usually require expensive apparatus and lengthy analytical time. As a contrast, fluorescence spectroscopy become a hot research topic in anion recognition and detection because of its high sensitivity and easy operation and other advantages in recent years. New bipyridinium salt L was designed and synthesized using pyrylium as a starting material. The molecular structure was determined by 1H NMR, 13C NMR, and high resolution mass spectrometry. The molecular recognition properties of L have been investigated through fluorescence titration experiments. The results indicate that L has sensitive and selective fluorescent response to NO3- among other different anions. Significant enhancements in the fluorescence intensity of L were observed when various concentrations of NO3- were added, while other competing anions have a quenching effect towards the initial fluorescence of solution. The fluorescence titration spectra shows that the bonding stoichiometry between receptor L and NO3- is 1 : 1 as a supramolecular complexes (1gK = 5 ± 0.02). The chemosensing properties of L were evaluated through quantum chemical calculations and the variable temperature 1H NMR titration. These results suggested that L has strong binding affinity towards NO3- with high selectivity, which may be ascribed to the specific hydrogen bonding between the L and active H atom of the bipyrydinium salts. The interaction between L and NO3- made the complex more planar compared with L giving rise to enhanced fluorescence and specific selectivity towards NO3-.