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BACKGROUND: Non-flaccid facial palsy sequelae manifest as sequelae following Bell's palsy. Currently, there are no effective remedies for addressing this issue. In this study, we proposed a new surgical solution, epineurectomy of the extracranial facial nerve trunk, and assessed its safety and efficacy as a potential remedy.. METHODS: In this single-arm trial, adult patients with non-flaccid facial palsy sequelae were enrolled and subjected to epineurectomy of the extracranial facial nerve trunk. The primary efficacy endpoint was the Sunnybrook scores at months 12 postoperatively. The secondary endpoints included non-flaccid facial palsy sequelae symptom scores, such as facial tightness or facial stiffness, facial synkinesis, eyefissures narrowing or difficulty in opening the eyes, House-Brackmann grade scale, and Facial Disability Index. RESULTS: A total of 22 patients were enrolled between July 2020 and January 2021. One patient was lost to follow up. One year after surgery, the Sunnybrook score was 72.0 (63.0 - 75.0) at 12 months versus 68.0 (58.0 - 70.8) at baseline. The mean difference was -5.4 (-7.2 to -3.6). The scores of facial tightness or facial stiffness, synkinesis, eye fissures narrowing or difficulty in opening eyes were 0.0 (0.0 - 1.0), 1.0 (1.0 - 1.0), 1.0 (1.0 - 2.0) at 12 months versus 3.0 (1.3 - 3.0), 2.0 (1.0 - 2.8), 2.0 (2.0 - 3.0) at baseline, respectively. The median (IQR) values of the Facial Disability Index physical function were 92.0 (90.0 - 95.0) at months 12, and the mean difference (95% CI) was -32 (-38 to -26) compared to baseline. The mean difference (95% CI) in the Facial Disability Index social/well-being function between month 12 and baseline was -38 (-46 to -31). CONCLUSIONS: Epineurectomy of the extracranial facial nerve trunk can effectively and safely alleviate the sequelae of non-flaccid facial palsy.

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INTRODUCTION: Preeclampsia (PE) is an immensely prevalent condition that poses a significant risk to both maternal and fetal health. It is recognized as a primary cause of perinatal morbidity and mortality. Despite extensive research efforts, the precise impact of JDP2 on trophoblast invasion and migration in the context of preeclampsia remains unclear. MATERIALS AND METHODS: The present study aimed to investigate the differential expression of JDP2 between normal control and preeclampsia placentas through the use of quantitative polymerase chain reaction (qPCR), western blotting, and immunostaining techniques. Furthermore, the effects of JDP2 overexpression and silencing on the migration, invasion, and wound healing capabilities of HTR-8/SVneo cells were evaluated. In addition, this study also examined the impact of JDP2 on epithelial-mesenchymal transition (EMT)-associated biomarkers and the Wnt/ß-catenin pathway. RESULTS: In the present investigation, it was ascertained that Jun dimerization protein 2 (JDP2) exhibited a substantial decrease in expression levels in placentae afflicted with preeclampsia in comparison to those of normal placentae. Impairment in migration and invasion was noted upon JDP2 down-regulation, whereas augmentation of migration and invasion was observed upon JDP2 overexpression in HTR-8/SVneo cells. Subsequently, western blot and immunofluorescence assays were conducted, revealing marked alterations in EMT-associated biomarkers, such as E-cadherin, N-cadherin, and ß-catenin, thereby indicating that JDP2 can facilitate cell invasion by modulating the EMT process in HTR-8/SVneo cells. Finally, activation of Wnt/ß-catenin signaling was observed as a result of JDP2. After that, IWR-1, a Wnt inhibitor, was used in the recovery study. IWR-1 could inhibit the role of JDP2 in promoting migration and invasion in HTR-8/SVneo cells. CONCLUSION: Our findings elucidated the impact of JDP2 on trophoblast invasion and migration in preeclampsia by suppressing the EMT through the Wnt/ß-catenin signaling pathway, thereby offering a potential prognostic and therapeutic biomarker for this condition.

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Objective: Meige syndrome (MS) is an adult-onset segmental dystonia for which no satisfactory remedy currently exists. Our team developed a novel surgical approach called bilateral trigeminal/facial nerve combing (BTFC). This study aimed to evaluate the outcomes of patients who underwent BFTC (Clinical Trial Registry Number: ChiCTR2000033481). Method: We assigned 22 patients with MS to undergo BTFC. The primary outcome was assessed using the movement subscale of the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS-M) at 12 months postoperatively. The second outcome was evaluated using the Medical Outcome Study (MOS) 36-item Short Form Health Survey (SF-36), the dysfunction subscale of the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS-D), and the sub-item scores of the BFMDRS-M. Safety outcomes included the House-Brackmann (HB) functional grading score and the visual analog scale (VAS) for facial numbness. Results: At the final follow-up at 12 months, the BFMDRS-M showed a mean improvement of 70.7% from baseline. Mean scores of the BFMDRS-M sub-motor (including the eyes, mouth, and speech/swallowing) improved by 65.6, 81.00, and 60%, respectively. The median score of the total BFMDRS-D score was 0.70 ± 1.17 compared with 1.86 ± 2.21 at baseline. There were no serious operative complications in this population. The quality of life of the patients significantly improved (P < 0.05). Conclusion: BFTC has proven to be effective in relieving the symptoms of Meige syndrome. This novel surgical approach offers a new alternative treatment for patients who have failed to respond to medications, botulinum toxin injections, and deep brain stimulation (DBS). Clinical Trial Registration: https://www.chictr.org.cn/bin/project/edit?pid=54567, ChiCTR2000033481.

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OBJECTIVE: Hypoglossal-facial nerve anastomosis (HFA) is the most commonly used surgical treatment for severe facial palsy that does not respond to conservative treatments. A major complication of HFA is the loss of tongue function. The authors aimed to evaluate whether anastomosing the transected hypoglossal nerve using the ramus descendens hypoglossi could prevent tongue deviation and dysfunction in patients undergoing HFA. METHODS: In this randomized trial, adult patients with severe peripheral facial palsy (House-Brackmann grade V or VI) who did not respond to at least 6 months of conservative treatment were randomized at a 1:1 ratio to undergo either HFA alone (control group) or HFA plus anastomosis between the hypoglossal nerve and descendens hypoglossi (intervention group). The primary endpoint was tongue deviation angle at 12 months. Key secondary endpoints included tongue disability (chewing difficulty, swallowing defect, and articulation defect), tongue disability index (TDI; range 1-4, with a higher score indicating more severe disability), and facial nerve function. RESULTS: Twenty patients were enrolled (10 in each group). At 12 months, the tongue deviation angle was significantly lower in the intervention group than in the control group (7.8° ± 5.1° vs 23.6° ± 9.6°, p < 0.001). Although not statistically significant, the intervention group had lower rates of chewing difficulty (1/10 vs 3/10, p = 0.58), swallowing defect (1/10 vs 5/10, p = 0.14), and articulation defect (2/10 vs 6/10, p = 0.17). TDI was significantly lower in the intervention group (1.5 ± 0.6 vs 2.5 ± 0.3, p < 0.001). The percentage of the patients achieving House-Brackmann grade II or III was 80% in each group. CONCLUSIONS: Anastomosis of the descendens hypoglossi to the transected hypoglossal nerve attenuated tongue deviation in patients undergoing HFA for facial palsy, without compromising facial nerve function. Clinical trial registration no: ChiCTR2000034372 (Chinese Clinical Trials Registry).

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Stepped spin crossover (SCO) complexes with three or more spin states have promising applications in high-order data storage, multi-switches and multi-sensors. Further synergy with other functionalities, such as luminescence and dielectric properties, will provide a good chance to develop novel multifunctional SCO materials. Here, a bent pillar ligand and luminescent pyrene guest are integrated into a three-dimensional (3D) Hofmann-type metal-organic framework (MOF) [Fe(dpoda){Au(CN)2}2]·pyrene (dpoda = 2,5-di-(pyridyl)-1,3,4-oxadiazole). The magnetic data show an incomplete and two-step SCO behavior with the sequence of 1 ↔ 1/2 ↔ 1/4. The rare bi-directional light-induced excited spin-state trapping (LIESST) effect and light-induced stepped thermal relaxation after LIESST are observed. The pyrene guests interact with dpoda ligands via offset face-to-face π⋯π interactions to form intermolecular exciplex emissions. The competition between thermal quenching and stepped SCO properties results in a complicated and stepped exciplex fluorescence. Moreover, the stepped dielectric property with higher dielectric permittivity at lower temperature may be related to the more frustrated octahedral distortion parameters in the intermediate spin states. Hence, a 3D Hofmann-type MOF with bent pillar ligands and fluorescent guests illustrates an effective way for the development of multifunctional switching materials.

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BACKGROUND: Interferon gene stimulator (Sting) is an indispensable adaptor protein that plays a crucial role in acute lung injury (ALI) induced by sepsis, and the PARP-1/NLRP3 signaling pathway may be an integral component of the inflammatory response mediated by Sting. However, the regulatory role of Sting in the PARP-1/NLRP3 pathway in ALI remains insufficiently elucidated. METHODS: Using lipopolysaccharide (LPS) to induce ALI in C57BL/6 mice and HUVEC cells, an in vivo and in vitro model was established. In vivo, Sting agonists and inhibitors were administered, while in vitro, Sting was knocked down using siRNA. ELISA was employed to quantify the levels of IL-1ß, IL-6, and TNF-α. TUNEL staining was conducted to assess cellular apoptosis, while co-immunoprecipitation was utilized to investigate the interaction between Sting and NLRP3. Expression levels of Sting, NLRP3, PARP-1, among others, were assessed via Western blotting and RT-qPCR. Lung HE staining and lung wet/dry ratio were evaluated in the in vivo mouse model. To validate the role of the PARP-1/NLRP3 signaling pathway, PARP-1 inhibitors were employed both in vivo and in vitro. RESULTS: In vitro experiments revealed that the Sting agonist group exacerbated LPS-induced pulmonary pathological damage, pulmonary edema, inflammatory response (increased levels of IL-6, TNF-α, and IL-1ß), and cellular injury, whereas the Sting inhibitor group significantly ameliorated the aforementioned injuries, with further improvement observed in the combination therapy of Sting inhibitor and PARP-1 inhibitor. Western blotting and RT-qPCR results demonstrated significant suppression of ICAM-1, VCAM-1, NLRP3, and PARP-1 expression in the Sting inhibitor group, with this reduction further enhanced in the Sting inhibitor + PARP-1 inhibitor treatment group, exhibiting opposite outcomes to the agonist. Furthermore, in vitro experiments using HUVEC cell lines validated these findings. CONCLUSIONS: Our study provides new insights into the roles of Sting and the PARP-1/NLRP3 signaling pathway in inflammatory responses, offering novel targets for the development of therapeutic interventions against inflammatory reactions.

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Background: Facial nerves have the potential for regeneration following injury, but this process is often challenging and slow. Schwann cells (SCs) are pivotal in this process. Bone mesenchymal stem cells (BMSC)-derived exosomes promote tissue repair through paracrine action, with hypoxic preconditioning enhancing their effects. The main purpose of this study was to determine whether hypoxia-preconditioned BMSC-derived exosomes (Hypo-Exos) exhibit a greater therapeutic effect on facial nerve repair/regeneration and reveal the mechanism. Methods: CCK-8, EdU, Transwell, and ELISA assays were used to evaluate the functions of Hypo-Exos in SCs. Histological analysis and Vibrissae Movements (VMs) recovery were used to evaluate the therapeutic effects of Hypo-Exos in rat model. circRNA array was used to identify the significantly differentially expressed exosomal circRNAs between normoxia-preconditioned BMSC-derived exosomes (Nor-Exos) and Hypo-Exos. miRDB, TargetScan, double luciferase assay, qRT-PCR and WB were used to predict and identify potential exosomal cirRNA_Nkd2-complementary miRNAs and its target gene. The function of exosomal circRNA_Nkd2 in facial nerve repair/regeneration was evaluated by cell and animal experiments. Results: This study confirmed that Hypo-Exos more effectively promote SCs proliferation, migration, and paracrine function, accelerating facial nerve repair following facial nerve injury (FNI) compared with Nor-Exos. Furthermore, circRNA analysis identified significant enrichment of circRNA_Nkd2 in Hypo-Exos compared with Nor-Exos. Exosomal circRNA_Nkd2 positively regulates mediator complex subunit 19 (MED19) expression by sponging rno-miR-214-3p. Conclusion: Our results demonstrated a mechanism by which Hypo-Exos enhanced SCs proliferation, migration, and paracrine function and facial nerve repair and regeneration following FNI through the circRNA_Nkd2/miR-214-3p/Med19 axis. Hypoxic preconditioning is an effective and promising method for optimizing the therapeutic action of BMSC-derived exosomes in FNI.

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The combination of chirality and phase-transition materials has broad application prospects. Therefore, based on the quasi-spherical theory and the thought strategy of introducing chirality, we have successfully synthesized a pair of chiral enantiomeric ligands (R/S)-triethyl-(2-hydroxypropyl)ammonium iodide, which can be combined with a tin hexachloride anion to obtain a pair of new organic-inorganic hybrid enantiomeric high-temperature plastic phase-transition materials: (R/S)-[CH3 CH(OH)CH2 N(CH2 CH3 )3 ]2 SnCl6 (1-R/1-S), which have a high temperature phase transition of Tc =384 K, crystallize in the P21 chiral space group at room temperature, and have obvious CD signals. In addition, compounds 1-R and 1-S have a good low-loss dielectric switch and broadband gap. This work is conducive to the research into chiral high-temperature reversible plastic phase-transition materials, and promotes the development of multi-functional phase-transition materials.

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Acute liver injury (ALI) may manifest at any phase of sepsis, yet an explicit therapeutic approach remains elusive. In this study, LPS and cecum ligation and puncture (CLP) were utilized to establish an inflammatory cell model and a murine model of sepsis-induced liver injury, respectively, aiming to explore the potential protective effect of protein interacting with C α kinase 1 (PICK1) on sepsis-induced ALI and its underlying mechanisms. In both the cell supernatant and the murine whole blood, the concentrations of inflammatory factors were quantified by ELISA, while the protein and mRNA expressions of PICK1, cleaved-PARP-1, caspase1, TLR4, IκBα, and NF-κB were assessed via western blot and qRT-PCR. The outcomes revealed that the knockdown of PICK1 increased the levels of inflammatory factors and apoptosis, alongside activation of TLR4/NF-κB signaling pathway-related factors in both in vivo and in vitro models. Moreover, the murine liver samples were subjected to Hematoxylin-Eosin (HE) staining for assessment of histopathological morphology. The HE staining and liver injury scoring results manifested a markedly exacerbated hepatic damage in PICK1 knockout mice as compared to WT mice following CLP. Furthermore, the liver macrophages were isolated from murine livers, and the expression and activity of the factors associated with the TLR4/NF-κB signaling pathway were verified through RT-qPCR and western blot, and EMSA assay demonstrated an augmented NF-κB activity subsequent to PICK1 knockout. Finally, the expression and localization of PICK1 in macrophages were further scrutinized via immunofluorescence, and the interaction between PICK1 and TLR4 was identified through co-immunoprecipitation. In conclusion, the knockdown of PICK1 appeared to modulate inflammatory factors by activating the TLR4/NF-κB signaling pathway, thereby exacerbating hepatic damage induced by sepsis.

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Ferroelectric materials are not only important electronic functional materials, but also considered as the most promising intelligent basic materials, because they show good application prospects. Therefore, it is an urgent task to develop and explore new ferroelectric material systems. In addition, the most important feature of crown ethers is their ability to complex with positive ions, which is extremely useful in synthesis. We report that [NH3C2H4Cl(18-crown-6)](CF3SO3) (1) has a phase transition temperature Tc = 255 K, and there is an obvious SHG switch below Tc. At the same time, the saturation polarization value Ps = 1.25 µC cm-2 is obtained from the hysteresis loop, which directly proves the ferroelectric nature of compound 1. It is noteworthy that the second harmonic response test of compound 1 shows a symmetric transition from a non-centrosymmetric to a centrosymmetric point group, that is a symmetry break from the paraelectric phase to the ferroelectric phase. This work is expected to promote the further exploration of organic crown ether ferroelectrics and provide a way to design and synthesize organic crown ether ferroelectrics.

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Background: Peripheral-type facial palsy could be caused by a lesion in the tegmentum of the pons, such as infarction, with a rare occurrence. We herein described a case of unilateral peripheral-type facial palsy induced by dorsolateral pontine infarction and treated this patient using modified hypoglossal-facial nerve anastomosis. Case presentation: A 60-year-old female presented with dizziness, hearing drop, diplopia, and peripheral-type facial palsy. Brain Magnetic Resonance Imaging showed a dorsolateral pontine infarction on the right side which exactly refers to the location of the ipsilateral facial nucleus or facial nerve fascicles at the pons. Subsequent electrophysiological examinations confirmed poor facial nerve function of this patient and modified hypoglossal-facial nerve anastomosis was then performed. Conclusions: This case reminded medical practitioners not to ignore the possibility of involvement of a central cause in peripheral-type facial palsy patients. In addition, modified hypoglossal-facial nerve anastomosis served as a useful skill improvement that may help reduce hemiglossal dysfunction while restoring facial muscle function.

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Since the switchable spontaneous polarization of ferroelectric materials endows it with many useful properties such as a large pyroelectric coefficient, switchable spontaneous polarization, and semiconductor, it has a wide range of application prospects, and the research of high-performance molecular ferroelectric materials has become a hot spot. We obtained a 0D organic-inorganic hybrid ferroelectric [(CH3)3NCH2CH2CH3]2FeCl4 (1) with well-defined ferroelectric domains and excellent domain inversion and exhibited a relatively large spontaneous polarization (Ps = 9 µC/m-2) and a Curie temperature (Tc) of 394 K. Furthermore, compound 1 belongs to the non-centrosymmetrical space group Cmc21 and has a strong second-harmonic generation signal. Interestingly, we also performed magnetic tests on 1, which confirmed that it is a magnetic material. This work provides clues for exploring the application of high-performance molecular ferroelectric materials in future multifunctional smart devices.

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One dimensional (1D) organic-inorganic halide hybrid perovskites have the advantages of excellent organic cation modifiability and diversity of inorganic framework structures, which cannot be ignored in the development of multi-functional phase-transition materials in photoelectric and photovoltaic devices. Here, we have successfully modified and synthesized an organic-inorganic hybrid perovskite photoelectric multifunctional phase-transition material: [C7 H13 ONCH2 F]⋅PbBr3 (1). The synergistic effect of the order double disorder transition of organic cations and the change of the degree of distortion of the inorganic framework leads to its high temperature reversible phase-transition point of Tc =374 K/346 K and its ultra-low loss high-quality dielectric switch response. Through in-depth research and calculation, compound 1 also has excellent semiconductor characteristics with a band gap of 3.06 eV and the photoluminescence characteristics of self-trapped exciton (STE) broadband emission. Undoubtedly, this modification strategy provides a new choice for the research field of organic-inorganic hybrid perovskite reversible phase-transition photoelectric multifunctional materials with rich coupling properties.

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Plastic crystals, as a molecular material with multiple functions, have become a research hotspot in the exploration of new ferroelectric crystal compounds, especially due to their unique solid-solid phase transition properties. Based on this, we synthesized a new 0D organic-inorganic hybrid Fe-based plastic ferroelectric [(CH3)3NCH2CHCH2]FeCl4 (1), which has a high-temperature phase transition point of 393 K, obvious ferroelectric domains, and spontaneous polarization and has been tested by dielectric and piezoelectric power microscopy (PFM) and ultraviolet absorption (UV-vis). At room temperature, it crystallizes in the space group Cmc21 and has an obvious SHG switch. In addition, compound 1 also has an optical narrow band gap of 2.45 eV, indicating that compound 1 is a high-quality semiconductor material. This work advances the development of plastic ferroelectrics and provides an avenue for exploring the frequency-doubling response and optoelectronic properties of high-temperature plastic ferroelectrics.

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BACKGROUND: The anterior quadratus lumborum block (QLB) is gaining popularity in total hip arthroplasty (THA) surgeries for postoperative pain management and this technique rarely results in lower limb muscle weakness. However, no studies have described the range of its blockade. OBJECTIVES: The aim of the study was to confirm the range of cold temperature sensory blockades, observe the opioid consumption after THA surgery, assess the pain of the patients, and assess the safety of this technique. STUDY DESIGN: Randomized controlled study. SETTING: Taizhou Hospital of Zhejiang Province. METHODS: Patients who underwent primary THAs were randomized to take an oblique sagittal anterior QLB with 30 mL of 0.375% ropivacaine (QLB+G group) or with 30 mL of 0.9% saline (G group). The main purpose of the study was to confirm the range of cold hypoesthesia. The other aim included the average blood pressure, heart rate, surgical pleth index, and bispectral index values fluctuation during the intraoperative period of expanding the medullary cavity, the sufentanil, and remifentanil consumption during the operation, the amount of time the patients stayed in the Postanesthesia Care Unit, the 8 hours, 16 hours, and 24 hours total dosage of oxycodone, the resting and exercise Visual Analog Scale (VAS) pain scores at 8 hours, 16 hours, and 24 hours after surgery, postoperative adverse events, and safety. RESULTS: The QLB+G group identified areas  of cold hypoesthesia after the block, but there were no areas of cold hypoesthesia in the G group. The consumption of oxycodone in the 8 hours, 16 hours, and 24 hours after the surgery and the consumption of sufentanil during the surgery were significantly smaller in the QLB+G group (P < 0.05). The QLB+G group have lower pain scores at the resting 8 hours and exercise 8 hours, 16 hours, and 24 hours after the surgery (P < 0.05). The 2 groups have comparable safety in the study. LIMITATIONS: This study only tested the areas of cold hypoesthesia after the QLB, but not tested the area of sensory loss. Using ice to test for hypoesthesia is subjective, and may not reflect the actual area of the block. CONCLUSIONS: Ultrasound-guided oblique sagittal anterior QLB can reduce the analgesics required after and during THA and the postoperative VAS pain scores, but it rarely affects muscle strength.

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OBJECTIVE: To discuss effect of intraoperative compound abnormal muscle response (AMR) in patients undergoing microvascular decompression (MVD) for hemifacial spasm (HFS). METHODS: Eighty-six HFS patients were underwent single or compound AMR monitoring during MVD. Single AMR recording was from the frontal muscle by stimulation of the marginal mandibular branch. Compound AMR recordings were obtained from the orbicularis oris and mentalis muscles by electrical stimulation of the temporal branch of the facial nerve, and from the frontal and orbicularis oculi muscles by stimulation of the marginal mandibular branch. Clinical outcome was compared with compound AMR results at the completion of MVD. RESULTS: Forty-two of 45 patients' AMR were recorded by compound AMR monitoring and 34 of 41 patients' AMR were recorded by single AMR monitoring during MVD. Hemifacial spasm resolved completely in 41 patients whose compound AMR was recorded and in 26 patients whose single AMR was recorded. Compound AMR gained a sensitivity of 96.3% and a specificity of 97.2%. Correspondingly, single AMR gained a sensitivity of 97.1% and a specificity of 86.3%. CONCLUSIONS: Our results suggest that compound AMR is more suitable than single AMR in MVD for HFS.

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Chiral organic-inorganic hybrid perovskites have gained extensive research interest due to their combination of chirality and the excellent optical, electrical and spin properties of perovskite materials, especially in two-dimensional hybrid perovskites. Herein, we report two-dimensional organic-inorganic perovskite enantiomeric ferroelectric [(R)-ß-MPA]2CdCl4 (1) and [(S)-ß-MPA]2CdCl4 (2) (MPA+ =methylphenethylammonium). Their mirror relationships are verified by both circular dichroism (CD) and crystal structures. At the same time, the two exhibit very similar ferroelectricity and related properties, including high Curie temperature (343 K), large spontaneous polarization (4.65 µC cm-2), and low coercive force field (13 kV cm-1). Unusually, at room temperature the crystal phase is monoclinic with the space group C2 and above the phase transition temperature it is triclinic with the space group P1, which means that the symmetry decreases with the increase of temperature. In addition, it exhibits a flexible switchable SHG response, while [(R)-ß-MPA]2CdCl4 and [(S)-ß-MPA]2CdCl4 have wide band gaps of 4.21 and 4.26 eV, respectively, mainly contributed by inorganic CdCl6 octahedra. This discovery opens a new way for the construction of two-dimensional enantiomeric molecular ferroelectrics.

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A novel organic-inorganic hybrid perovskite crystal, [ClC6H4(CH2)2NH3]2CuBr4 (1), having experienced an invertible high-temperature phase transition near Tc (the Curie temperature Tc = 355 K), has been successfully synthesized. The phase-transition characteristics for compound 1 are thoroughly revealed by specific heat capacity (Cp), differential thermal analysis, and differential scanning calorimetry tests, possessing 16 K broad thermal hysteresis. Multiple-temperature powder X-ray diffraction analysis further proves the phase-transition behavior of compound 1. Moreover, compound 1 exhibits a significant steplike dielectric response near Tc, revealing that it can be deemed to be a promising dielectric switching material. The variable-temperature fluorescence experiments show distinct photoluminescence (PL) changes of compound 1. Further investigation and calculation disclose that the fluorescence lifetime of compound 1 can reach as long as 55.46 µs, indicating that it can be a potential PL material. All of these researches contribute a substitutable avenue in the design and construction of neoteric phase-transition compounds combining high Curie temperature and PL properties.

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Low-dimensional chiral organic-inorganic hybrid metal halides have attracted a lot of attention in recent years due to their unique intrinsic properties, including having potential applications in optoelectronic and spintronic devices. However, low-dimensional chiral molecular ferroelectrics are very rare. In this paper, we report a novel zero-dimensional molecular ferroelectric (C9H14N)2CdBr4 (C9H14N+ = protonated 3-phenylpropylamine), which has obvious dielectric and thermal anomalies and shows a high Curie temperature at 395 K. It crystallizes in the P21 space group at room temperature, showing a strong CD signal, large spontaneous polarization (P s = 13.5 µC cm-2), and a clear ferroelectric domain. In addition, it also exhibits a flexible SHG response. The photoluminescence spectrum shows that 1 has broadband luminescence. At the same time, compound 1 has a wide band gap, which is mainly contributed to by the inorganic CdBr4 tetrahedron. The high tunability of low-dimensional chiral molecular ferroelectrics also opens up a way to explore multifunctional chiral materials.

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Bistable switches (electrical switching between "ON" and "OFF" bistable states) have gradually developed into an ideal category of highly intelligent materials, due to their significant applications in optical technology, signal processors, data storage and other switchable media applications in the field of electrical devices. Here, we successfully designed and synthesized [(FC6 H4 C2 H4 NH3 )2 MCl4 ]n (FC6 H4 C2 H4 NH3 + )=deprotonated 4-fluoro- phenethylamine; M=Cd (1), Mn (2)), which realized the coupling of thermo-dielectric switching characteristics, semi-conductor characteristics and photo-luminescent properties. DSC (differential scanning calorimetry) and dielectric measurements show that 1 is a sensitive dielectric bistable switch between the high dielectric (ON) and low dielectric (OFF) states. The temperature-variable single crystal structure shows that the both 1 and 2 undergo a high-temperature reversible phase transition around 383 K/380 K, which is caused by the order-disordered transformation of organic cations and the slight distortion of the inorganic framework. In particular, 1 shows outstanding switchable dielectric behavior and semiconducting properties. Further, 1 and 2 emit strong green and yellow luminescence at 527 and 595 nm, respectively.