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(Pb0.87Ba0.1La0.02)(Zr0.68Sn0.24Ti0.08)O3 ( PBLZST) antiferroelectric ( AFE) ceramics have been prepared by hot-press sintering method and conventional solid-state reaction process, and the dependence of microstructure and energy storage properties of the ceramics on sintering approaches has been studied. The results reveal that not only the microstructure, but also the electrical properties of the PBLZST AFE ceramics are significantly improved by using the hot-press sintering method. Samples resulting from the hot-press sintering process have high breakdown strength of 180 kV/cm which results from the increase of density. Coupled with large polarization, the hot-pressed AFE ceramics are shown to have a high recoverable energy density of 3.2 J/cm3. The recoverable energy density of the hot-pressed PBLZST AFE ceramics is 100% greater than the conventional sintered specimens with recoverable energy density of 1.6 J/cm3. [ABSTRACT FROM AUTHOR]

The β-phase of poly(vinylidene fluoride) (PVDF) is of great technical importance because of its high dielectric constant and piezoelectric effect. In this work, we exfoliated and dispersed natural graphite to prepare 2D-graphite nanosheets (GNS) and prepared PVDF/GNS nanocomposites with different GNS volumes from 1 to 7 ml as film via solution casting method. The concentration of the supernatant was about 0.3 mg/mL. The effect of GNS on the β-phase formation and mechanisms of piezoelectric formation in the PVDF/GNS nanocomposites were investigated. The results showed that with the varying amounts of GNS, the crystalline structure, the morphology, and the dielectric and piezoelectric properties of PVDF/GNS nanocomposites changed. GNS acts as an effective nucleation agent with the orientation almost parallel to the surface of the film meanwhile increasing the amount of beta phase in the PVDF matrix with increasing amount of GNS, also the relative dielectric constant and dielectric loss of the nanocomposites increased with increasing amount of GNS. The value d also increased with increasing amount of GNS, and reached a maximum (6.7 pC/N) with 6 ml GNS. The mechanism of piezoelectric formation was proposed based on experiment results of PVDF/GNS nanocomposites. [ABSTRACT FROM AUTHOR]

(PbLaBa)(ZrSnTi)O (PLBZST, 0.06≤ x≤0.09) antiferroelectric ceramics were fabricated by conventional solid state reaction process, and their ferroelectric, dielectric, and pyroelectric properties were systemically investigated. PLBZST with different Ti content were all confirmed to be in an antiferroelectric phase at T=50°C, which is close to the lowest phase transition temperature. Compared with conventional FE ceramics, PLBZST antiferroelectric ceramics exhibited higher electric field induced pyroelectric coefficient ( p). As the content of Ti increased from 0.06 to 0.09, the pyroelectric coefficient increased from 1000 to 6500 μC/mK under a 500 V/mm DC bias field. The maximum pyroelectric coefficient of 8400 μC/mK was obtained at x=0.09 when an 850 V/mm DC bias field was applied, which is far larger than that of conventional phase transition pyroelectric materials. Large pyroelectric response is beneficial for the development of infrared detectors and thermal imaging sensors. [ABSTRACT FROM AUTHOR]

Abstract: (Pb0.87Ba0.1La0.02)(Zr0.68Sn0.24Ti0.08)O3 anti-ferroelectric ceramics with various amounts of excess PbO have been fabricated by the conventional solid-state reaction process and the hot-press sintering method, and the dependence of microstructure, ferroelectric and dielectric properties on sintering approaches and lead volatilization conditions has been studied. When an appropriate quantity of excess PbO is added, the lead volatilization effect can be compensated and the content of pyrochlore phase is decreased. Hot-pressed anti-ferroelectric ceramics exhibit much higher densities than conventionally sintered samples. The spontaneous polarization and maximum dielectric constant of the AFE ceramics decrease when the hot-press sintering method is used. The dielectric loss can be obviously reduced by using the hot-press sintering method and adding a proper amount of excess PbO. The systemic investigation of the lead volatilization effect and the hot-press sintering method will contribute to the development of high properties of anti-ferroelectric ceramics in practical applications. [Copyright &y& Elsevier]

Plants subjected to cold stress have been observed to accumulate proline, but the underlying regulatory mechanism remains to be elucidated. In this study, we identified a pyrroline-5-carboxylate synthetase (P5CS)-encoding gene (CtrP5CS1) from trifoliate orange (Citrus trifoliata L.), a cold-hardy citrus species, as a critical gene for cold-induced proline accumulation. CtrTGA2 bound directly to the TGACG motif of the CtrP5CS1 promoter and activated its expression. Moreover, CtrTGA2 functioned positively in cold tolerance via modulation of proline synthesis by regulating CtrP5CS1 expression. Up-regulation of CtrP5CS1 and CtrTGA2 under cold stress was dependent on salicylic acid (SA) biosynthesis. CtrTGA2 directly regulated the expression of CtrICS1, a gene encoding isochorismate synthase (ICS) involved in SA biosynthesis, forming a positive feedback loop to intensify the CtrTGA2-mediated transcriptional activation of CtrP5CS1. The cold-induced SA receptor NONEXPRESSOR OF PATHOGENESIS-RELATED GENES3 (CtrNPR3) interacted with CtrTGA2 to inhibit its transcriptional activation activity; however, the inhibition was released by SA. Our results uncover the CtrTGA2-CtrP5CS1/CtrICS1 regulatory module that orchestrates the SA signal to regulate proline synthesis, giving important insights into the transcriptional mechanism underlying proline accumulation in plants under cold stress., Competing Interests: Conflict of interest statement. None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society of Plant Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Objective: To investigate the long-term outcome of laparoscope-assisted transanal total mesorectal excision (taTME) for rectal cancer., Methods: Clinicopathological data of 29 patients with mid-low rectal cancer undergoing laparoscope-assisted taTME at Department of Gastrointestinal Surgery, the First Affiliated Hospital of Guangzhou Medical University from May 2010 to December 2015 were collected for the retrospective case-series study. All the operations were performed with transabdominal and transanal procedure simultaneously or sequentially. Perioperative presentations, pathological examinations, and oncologic outcomes were retrospectively analyzed. Long-term recurrence, metastasis and survival were assessed during follow-up. Outpatient clinic and telephone survey were used for follow-up. The follow-up time ended in December 2018. The overall survival (OS) rate and disease-free survival (DFS) rate were calculated by the Kaplan-Meier method., Results: The average intra-operative blood loss was (75.9±9.5) ml (range,20 to 200). The average operating time was (223.6±4.1) minutes (range, 165 to 280). The average number of harvested lymph node was 22.3±2.0. The average length of pathological specimen was (13.1±0.6) cm. The average distal resection margin was (2.9±0.2) cm. 89.7% (26/29) of specimens was complete and 10.3% (3/29) near complete. Two cases (6.9%) had positive cutting circumferential margin. Median follow-up was 56 (range, 22 to 91) months. Local recurrence rate, distant metastasis rate, 3-year OS rate, 3-year DFS rate, 5-year OS rate, 5-year DFS rate were 10.3% (3/29), 20.7%(6/29), 96.6%, 83.2%, 87.6% and 79.6%, respectively. No incisional hernia or adhesive intestinal obstruction was found., Conclusion: Long-term outcomes of mid-low rectal cancer patients undergoing laparoscope-assisted taTME are satisfactory.