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We present a systematic experimental study on the phase transition, lattice microstrain, and order-disorder of cations for garnets in the majorite-pyrope system. Polycrystalline gem-quality garnets were synthesized at high pressure and high temperature using a Kawai-type multi-anvil apparatus. A phase transition from a cubic to tetragonal structure is clearly observed for garnets with the majorite content of more than 74 mol % through X-ray diffraction (XRD) and Raman scattering studies. Microstrain of garnets, evaluated with the Williamson-Hall plot on XRD profiles, shows a nonlinear dependence of the garnet compositions. The variation of the XRD peak broadening suggests the lattice microstrain of these garnets may be associated with the local structural heterogeneities due to the substitution of different cations via the coupled substitution (Mg + Si = 2Al) in the garnet structure. The width variation of Raman scattering peaks indicates that cation disorder occurs in the garnet structure for intermediate compositions. It is found that intermediate garnets and end-members have a minimum of microstrain, while those between end-members and intermediate compositions possess a larger microstrain. [ABSTRACT FROM AUTHOR]

The elastic wave velocities of polycrystalline MjPy garnet along the majorite-pyrope system have been measured at pressures up to 21 GPa and temperatures up to 2,000 K using ultrasonic interferometry in conjunction with in situ X-ray diffraction techniques in a Kawai-type multi-anvil apparatus. The elastic moduli of MjPy garnet and their pressure and temperature derivatives are determined by a two-dimensional linear fitting of the present experimental data, yielding: K = 161.5 (7) GPa , ∂K/ ∂P = 4.42 (4) , ∂K/ ∂T = −0.0154 (2) GPa/K , G = 86.2 (2) GPa , ∂G/ ∂P = 1.28 (1) , ∂G/ ∂T = −0.0096 (5) GPa/K. The present results together with those of the studies on the majorite-pyrope solid solutions suggest the pressure and temperature derivatives of elastic moduli are insensitive to the majorite content in the majorite-pyrope system. The velocity gradients of the majoritic garnets in the majorite-pyrope system are 3 ~ 6 times lower than those required to account for the high seismic velocity gradients observed in the mantle transition zone. [ABSTRACT FROM AUTHOR]

This study aimed at developing an effective pregnancy outcome prediction nomogram after surgical anastomosis of the oviduct. This was a retrospective cohort study involving hospitalized women who underwent oviduct anastomosis between January 2008 and January 2019. Socio-demographic and clinical characteristics data of patients were extracted from online records. Univariate and multivariate Cox analyses were performed on selected variables after which multivariate Cox regression analyses used to construct a nomogram for prediction of pregnancy outcomes. C-statistics (C-index) and calibration curves were used to validate the nomogram. A total of 247 women were enrolled in the study. Among them, 67.2% (167 women) had successful live intrauterine pregnancy and 50.6% had at least one live birth. Univariate Cox analysis revealed that patients older than 35 years (HR 0.56; 95% CI 0.41–0.76), post-operative tubal length less than 7 cm (HR 0.36; 95% CI 0.21–0.63), sterilization reversal by laparoscopy (HR 1.38; 95% CI 1.01–1.87), and pelvic environment (HR 0.80; 95% CI 0.68–0.94) were significantly associated with post-surgical intrauterine pregnancy. Based on multivariate Cox analysis, the independent prognostic factors were established to be age > 35 years, post-operative tubal length < 7 cm, sterilization reversal by laparoscopy, and pelvic environment. The constructed predictive model exhibited a good discrimination and predictive ability for intrauterine pregnancy after surgery (C-index 0.74). Sterilization reversal by laparoscopy, post-operative tubal length ≥ 7 cm, age ≤ 35 years, and normal pelvic environment were associated with better pregnancy outcomes after surgical anastomosis of the oviduct. Surgical repair of the fallopian tube partially reverses and restores the anterior natural fertility of women. [ABSTRACT FROM AUTHOR]

(1-x)(0.75Na0.5Bi0.5TiO3-0.25SrTiO3)-xErBiO3 (NBST-xEB, x = 0–0.04) ceramics were fabricated through a solid state reaction method. Scanning electron microscopy investigation shows that grain size of the ceramics decreases with increasing x. X-ray diffraction results reveal that all the ceramics are pseudocubic phase. An enhanced disordering of local structure by EB doping is revealed by Raman spectra. The NBST-xEB ceramics exhibit excellent dielectric stability within a wide temperature range after EB doping. A relatively high recoverable energy storage density (Wrec) of 1.834 J/cm3 with efficiency (η) of 71% are obtained for NBST-0.02 EB ceramics under a moderate electric field of 148 kV/cm. The Wrec and η of the NBST-0.02 EB ceramics exhibit excellent fatigue stability (104) and temperature stability (Wrec > 0.834 J/cm3, η > 64%) within 30–200 °C under 100 kV/cm. With the introduction of EB, the NBST-xEB ceramics also show strong photoluminescence properties due to the presence of Er3+. [ABSTRACT FROM AUTHOR]

The thermal effect of the Tibetan Plateau (TP) on the northern hemisphere climate has long been a hot topic of scientific research. However, the global effects of the TP heat source are still unclear. We investigate the teleconnection patterns coincident with the TP heat source in boreal summer using both observational data and numerical models including a linearized baroclinic model and an atmospheric general circulation model. The western TP shows the most intense variability in atmospheric heating and the most active connection to atmospheric circulations. The surface sensible heating component of the western TP heat source is associated with a high-latitude wave train propagating from North Japan to central North America through the Bering Sea and Canada. The radiative heating component is accompanied by a wavenumber-4 wave train over Eurasia. We focus on the global zonally-oriented pattern that is connected with the latent heat release from the western TP, referred to here as the TP–circumglobal teleconnection (TP-CGT). The TP-CGT pattern is triggered by the western TP latent heating in two parts starting from the TP: an eastward-propagating wave train trapped in the westerly jet stream and a westward Rossby wave response. The TP-CGT accounts for above 18% of the total variance of the circumglobal teleconnection pattern and modulates mid-latitude precipitation by superimposition. The western TP is the key region in which diabatic heating can initiate the two atmospheric responses concurrently, and the heating over northeastern Asia or the Indian Peninsula is unable to induce the circumglobal pattern directly. The unique geographical location and strong tropospheric heating also make the western TP as a "transit area" of transferring the indirect impact of the Indian summer monsoon (ISM) to the TP-CGT. These results enhance our understanding of the relationship between the circumglobal teleconnection and the ISM and is helpful for improving the prediction of the circumglobal teleconnection variability. [ABSTRACT FROM AUTHOR]

We present an experimental study of a new hybrid material where nitrogen is encapsulated in the channels of porous zeolite AlPO4-5 (AFI) single crystals by a high-pressure method. The high-pressure behavior of nitrogen confined inside the AFI nano-channels is then investigated by Raman spectroscopy up to 44 GPa. Under pressure, the Raman modes of confined nitrogen show behaviors different from those of the bulk nitrogen. After the return to atmospheric pressure, it is demonstrated that non-gaseous nitrogen can be effectively stabilized by being confined inside the intact AFI sample. This result provides new insight into nitrogen capture and storage technologies. [ABSTRACT FROM AUTHOR]