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Transient implantable piezoelectric materials are desirable for biosensing, drug delivery, tissue regeneration, and antimicrobial and tumor therapy. For use in the human body, they must show flexibility, biocompatibility, and biodegradability. These requirements are challenging for conventional inorganic piezoelectric oxides and piezoelectric polymers. We discovered high piezoelectricity in a molecular crystal HOCH2(CF2)3CH2OH [2,2,3,3,4,4-hexafluoropentane-1,5-diol (HFPD)] with a large piezoelectric coefficient d33 of ~138 picocoulombs per newton and piezoelectric voltage constant g33 of ~2450 × 10−3 volt-meters per newton under no poling conditions, which also exhibits good biocompatibility toward biological cells and desirable biodegradation and biosafety in physiological environments. HFPD can be composite with polyvinyl alcohol to form flexible piezoelectric films with a d33 of 34.3 picocoulombs per newton. Our material demonstrates the ability for molecular crystals to have attractive piezoelectric properties and should be of interest for applications in transient implantable electromechanical devices. [ABSTRACT FROM AUTHOR]

An ultrasensitive photoelectrochemical (PEC) aptasensor was originally designed by using ZnIn2S4/ReS2 as a photoactive material and AgInS2 as a signal amplifier. The signal amplifier AgInS2 was incubated on the terminal of H-DNA (immobilized on the ZnIn2S4/ReS2/FTO surface), leading to an enhanced photocurrent response. Then, due to the introduction of DNA2, the formation of a double-stranded structure caused AgInS2 to keep away from the electrode surface, and the photocurrent was reduced. In the presence of kanamycin, DNA2 was released from the system due to the competition relationship, and a restored photocurrent response was obtained. The combination of ZnIn2S4/ReS2 and AgInS2 accelerated the electron transfer and enhanced the separation efficiency of photogenerated electron–hole pairs, resulting in an improved performance of the PEC aptasensor, which was capable of accurate and sensitive detection of kanamycin in actual samples. [ABSTRACT FROM AUTHOR]

ABSTRACT: Objective: To present a case of Langerhans cell histiocytosis (LCH) involving the pituitary and thyroid that was misdiagnosed as idiopathic diabetes insipidus (DI) and Hashimoto thyroiditis.Methods: The history, clinical findings, laboratory and imaging results, management, and follow-up of the case are presented, and the endocrine involvement is discussed.Results: A 50-year-old female with a 13-year history of DI and a 5-year history of progressive goiter with hypothyroidism had been initially diagnosed with idiopathic DI and Hashimoto thyroiditis. She also had a 10-year history of diabetes mellitus (DM). A partial thyroidectomy was conducted when the goiter caused dyspnea, and the postoperative pathological results suggested LCH. After a thorough examination, the diagnosis of LCH was confirmed, and the patient was treated with chemotherapy and radiotherapy. After the treatment, she went into persistent remission.Conclusion: LCH cases mainly presenting as endocrine disorders are very rare, and the diagnosis tends to be delayed or missed due to atypical clinical manifestations. Lesions or functional disorders of the pituitary and thyroid need to be differentially diagnosed against LCH of these organs. Appropriate therapy and long-term follow-up are necessary for the management of endocrine LCH.Abbreviations: CT computed tomography DI diabetes insipidus DM diabetes mellitus LCH Langerhans cell histiocytosis MRI magnetic resonance imaging TSH thyroid-stimulating hormone

Organosilicons have been used extensively in aerospace, electronics, food, medicine and other fields, due to their low viscosity, hydrophobicity, corrosion resistance, non‐toxic, and physiologically inert features. Despite extensive interest, however, organosilicon ferroelectric crystals have never been found. Here, by using the chemical design strategy, we successfully obtained a molecular ferroelectric D‐chiro‐inositol‐SiMe3 with polar P43 symmetry, whose spontaneous polarization can be electrically switchable on thin film. The introduction of organosilicon groups endows the thin films with excellent softness, ductility and flexibility (extremely low hardness of 72.8 MPa and small elastic modulus of 5.04 GPa) that are desirable for biomedical and human‐compatible applications. As the first case of organosilicon ferroelectric crystal to date, this work offers a new structural paradigm for molecular ferroelectrics, and highlights their potential for flexible bio‐electronic applications. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskites (OIHPs) have gained tremendous interest for their rich functional properties. However, the coexistence of more than one of ferroelectricity, ferromagnetism and ferroelasticity has been rarely found in OIHPs. Herein, we report a two‐dimensional Cr2+‐based OIHP, [3,3‐difluorocyclobutylammonium]2CrCl4 ([DFCBA]2CrCl4), which shows both ferroelectricity and ferromagnetism. It undergoes a 4/mmmFm type ferroelectric phase transition at a temperature as high as 387 K and shows multiaxial ferroelectricity with a saturate polarization of 2.1 μC cm−2. It acts as a soft ferromagnet with a Curie temperature of 32.6 K. This work throws light on the exploration of OIHPs with the coexistence of ferroelectricity and ferromagnetism for applications in future multifunctional smart devices. [ABSTRACT FROM AUTHOR]

To explore whether there is a specific clinical effect of acupuncture in the treatment of chronic prostatitis. A total of 52 patients with chronic prostatitis were randomly divided into an acupuncture group (24 cases) and a placebo acupuncture group (28 cases). During the treatment, 1 case was dropped out in the placebo acupuncture group and 51 patients accomplished the clinical trial finally in two groups. In the acupuncture group, Shènshū (肾俞BL23), Zhōngliáo (中髎BL33), Huìyáng (会阳BL35) and Sānyīnjiāo (三阴交SP6) were selected. In the placebo acupuncture group, the non-meridian points located lateral to BL23, BL33, BL35 and SP6 were selected, respectively. The duration of treatment was 8 weeks in each group. In the first 4 weeks of treatment, the treatment was given once every two days, three times weekly. In the last 4 weeks of treatment, the treatment was given once every three days, twice a week. Totally, 20 acupuncture treatments were required in the whole trial. Before treatment, in week 4 and 8 of treatment and in follow-up, National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) score and the comprehensive effect were evaluated in the two groups successively. In week 4 and 8 of treatment, NIH-CPSI score in the acupuncture group was lower than that before treatment, respectively (both P < 0.05). In week 8 of treatment, NIH-CPSI score in the placebo acupuncture group was lower than that before treatment (P < 0.05). NIH-CPSI score in the acupuncture group was lower than the placebo acupuncture group in week 8 of treatment (P < 0.05). In follow-up, NIH-CPSI score of the two groups all decreased as compared with the score before treatment (both P < 0.05), and the score in the acupuncture group was lower than the placebo acupuncture group (P < 0.05). In the comparison of comprehensive effect, the total effective rate was 91.7% in the acupuncture group and was 74.1% in the placebo acupuncture group. The therapeutic effect in the acupuncture group was better than that of the placebo acupuncture group (P < 0.05). Acupuncture relieves pelvic pain and urination symptoms and has a certain of long-term effect in patients with chronic prostatitis. [ABSTRACT FROM AUTHOR]

This study investigates the effects of visual mnemonics and the methods of presenting learning materials on learning visually similar characters for Chinese-as-second-language (CSL) learners. In supporting CSL learners to build robust orthographic representations in Chinese, addressing the challenges of visual similarity of characters (e.g., 理 and 埋) is an important issue. Based on prior research on perceptual learning, we tested three strategies that differ in the extent to which they promote interrelated attention to the form and meaning of characters: (1) Stroke Sequence, a form-emphasis strategy, (2) Key-images, a form + meaning strategy utilizing visual code, (3) Pithy Formulas with Key-images, a form + meaning strategy combining visual and verbal codes. A pretest–posttest equivalent-group design was adopted. The independent variables were the learning strategy, the method of presenting character pairs (visually similar vs. dissimilar), and testing time. The dependent variables were learners' proportions of accurate responses to reading and writing Chinese characters through a posttest (immediately performed after learning) and a delayed posttest (1 week after learning); a learner experience survey was also administered to investigate learners' opinions on each strategy. Sixty-six non-beginning learners of Chinese participated; they were randomly assigned to one of the two groups in which participants learned ten characters via the three strategies, respectively, differing between whether the characters were presented in similar pairs or dissimilar pairs. Data were analyzed via three-way ANCOVAs. The Pithy Formulas with Key-images and the Key-images generally yielded higher writing accuracy than Stroke Sequence immediately after learning. Notably, the advantage of the Pithy Formulas with Key-images (verbal and visual) over the Key-images (visual) on writing was specific to the participants that learned with visually similar pairs rather than those that learned with dissimilar pairs. All strategies were effective for reading, yet learners' experience ratings favored the two form + meaning strategies over the strategy that focused primarily on form. Suggestions for future research and pedagogical implications on learning visually similar characters were offered. [ABSTRACT FROM AUTHOR]

We discovered that [(histamine)(18-crown-6)2][BF4]2 is a high-temperature host–guest inclusion complex that presents decent piezoelectric properties (d33 = 5 pC/N), undergoes a phase transition at 406 K, and also possesses potential ferroelectricity. This work provides a new idea for constructing host–guest inclusion piezoelectrics. [ABSTRACT FROM AUTHOR]

With prosperity, decay, and another spring, molecular ferroelectrics have passed a hundred years since Valasek first discovered ferroelectricity in the molecular compound Rochelle salt. Recently, the proposal of ferroelectrochemistry has injected new vigor into this century-old research field. It should be highlighted that piezoresponse force microscopy (PFM) technique, as a non-destructive imaging and manipulation method for ferroelectric domains at the nanoscale, can significantly speed up the design rate of molecular ferroelectrics as well as enhance the ferroelectric and piezoelectric performances relying on domain engineering. Herein, we provide a brief review of the contribution of the PFM technique toward assisting the design and performance optimization of molecular ferroelectrics. Relying on the relationship between ferroelectric domains and crystallography, together with other physical characteristics such as domain switching and piezoelectricity, we believe that the PFM technique can be effectively applied to assist the design of high-performance molecular ferroelectrics equipped with multifunctionality, and thereby facilitate their practical utilization in optics, electronics, magnetics, thermotics, and mechanics among others. [ABSTRACT FROM AUTHOR]

With the capability to manipulate the built‐in field in solar cells, ferroelectricity is found to be a promising attribute for harvesting solar energy in solar cell devices by influencing associated device parameters. Researchers have devoted themselves to the exploration of ferroelectric materials that simultaneously possess strong light absorption and good electric transport properties for a long time. Here, it is presented a novel and facile approach of combining state‐of‐art light absorption and electric transport properties with ferroelectricity by the incorporation of room temperature 1D ferroelectric perovskite with 3D organic–inorganic hybrid perovskite (OIHP). The 1D/3D mixed OIHP films are found to exhibit evident ferroelectric properties. It is notable that the poling of the 1D/3D mixed ferroelectric OIHP solar cell can increase the average Voc can be increased from 1.13 to 1.16 V, the average PCE from 20.7% to 21.5%. A maximum power conversion efficiency of 22.7%, along with an enhanced fill factor of over 80% and open‐circuit voltage of 1.19 V, can be achieved in the champion device. The enhancement is by virtue of reduced surface recombination by ferroelectricity‐induced modification of the built‐in field. The maximum power point tracking measurement substantiates the retention of ferroelectric‐polarization during the continued operation. [ABSTRACT FROM AUTHOR]

100 years have passed since the initiate of ferroelectrics, molecular ferroelectrics with homochirality. Although inorganic ceramics have gained widespread utilization, especially in electronic, optical, and energy harvesting devices, the development of a molecular ferroelectric is still in its infancy because of the difficulty in finding a new one, let alone controllably optimizing its performance. It is noteworthy that some recently developed chemical design approaches, including the ideas of quasi-spherical theory, introducing homochirality, and H/F substitution, significantly contribute to the chemical design as well as performance optimization of a wide range of molecular ferroelectrics. This, in fact, changes the way of discovering a new molecular ferroelectric from blind search into targeted design. In this Perspective, we lay out three key strategies for chemical design and performance optimization of molecular ferroelectrics, which are the vital components for ferroelectrochemistry and provide fresh insights into how to design a new molecular ferroelectric relying on the established methodology. This, undoubtedly, opens the floodgate in the development of molecular ferroelectrics, especially for their academic and commercial desire. We wish to briefly exhibit our systematical studies on the targeted design and performance optimization of molecular ferroelectrics and set off the trend of targeted design in the next 100 years for ferroelectrics. [ABSTRACT FROM AUTHOR]

Molecular ferroelectrics have attracted considerable interests because of their easy and environmentally friendly processing, low acoustical impedance and mechanical flexibility. Herein, a molecular thermochromic ferroelectric, N,N′‐dimethyl‐1,4‐diazoniabicyclo[2.2.2]octonium tetrachlorocuprate(II) ([DMe‐DABCO]CuCl4) is reported, which shows both excellent ferroelectricity and intriguing thermochromism. [DMe‐DABCO]CuCl4 undergoes a ferroelectric phase transition from Pca21 to Pbcm at a significantly high Curie temperature of 413 K, accompanied by a color change from yellow to red that is due to the remarkable deformation of [CuCl4]2− tetrahedron, where the ferroelectric and paraelectric phases correspond to yellow and red, respectively. Combined with multiple bistable physical properties, [DMe‐DABCO]CuCl4 would be a promising candidate for next‐generation smart devices, and should inspire further exploration of multifunctional molecular ferroelectrics. [ABSTRACT FROM AUTHOR]

Since the first perovskite CaTiO3 was discovered in 1839, the development of perovskite has a history of 180 years. The emergence of solar cells (CH3NH3)PbI3 has set off the trend of hybrid organic–inorganic perovskite (HOIP) materials. Since then, various HOIPs have sprung up and been widely used in various material devices. Among them, HOIP ferroelectrics have gained widespread attention. However, antiperovskite, as a twin brother of perovskite, has been neglected although it has similar structure with perovskite. Here, we successfully found that [C3H7FN]3[SnCl6]Cl has a three‐dimensional (3D) antiperovskite structure with the formula M3AB. Importantly, the compound exhibits obvious ferroelectric properties with an Aizu notation of 622F6 at 391 K. To the best of our knowledge, this is the first 3D hybrid organic–inorganic antiperovskite ferroelectric, which will greatly promote the development of antiperovskite families with more superior physical properties. [ABSTRACT FROM AUTHOR]

A host–guest inclusion compound, 18-crown-6 oxonium tetrachloride-gallium(III), was shown to undergo a 4/mmmFmm2-type ferroelectric phase transition with four crystallographically equivalent polarization directions at 337 K. To the best of our knowledge, this is the first host–guest inclusion compound shown to be a high-temperature multiaxial molecular ferroelectric. [ABSTRACT FROM AUTHOR]

Ferroelectric polarization is sensitive to external stimuli, such as temperature or pressure, the variation of which can induce a slight change in crystal structure. Similarly, for ferroelectric crystals in host–guest systems, the inclusion of different guest molecules can affect the crystal packing a small amount; however, it may alter the ferroelectric properties significantly. In this report, we discovered that the supramolecular host–guest system Cu(1,10-phen)2SeO4·(diol) (phen is the abbreviation of phenanthroline) can distinguish cis–trans isomers via physical signal feedback, i.e. dielectric/ferroelectric responses. The supramolecular crystal is nonferroelectric and shows inconspicuous dielectric behavior when trans-1,2-cyclohexanediol is included, while a ferroelectric system is achieved when the host interacts with cis-1,2-cyclohexanediol. Moreover, the ferroelectric–paraelectric phase transition involved in cis-1,2-cyclohexanediol occurs together with an interesting chair-boat conformation change, as well as an order–disorder transition. As far as we know, this is the first discovery showing that dielectric/ferroelectric signal responses can be used to distinguish cis–trans isomers in the field of ferroelectric materials. This finding enriches studies of the molecular ferroelectric family and might provide inspiration for smart device design. [ABSTRACT FROM AUTHOR]

The significant Tc enhancement of 110 K in [N-fluoromethyldabconium] triiodide lead caused by the promising design of H/F substitution is the first and unprecedented, opening up an applicable and universal strategy to effectively regulate the Tc working temperature in phase transition materials. [ABSTRACT FROM AUTHOR]