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Coordination of uranium chemistry by multiligands has attracted attention as a way to obtain unique molecular structures and their possible use in environmental and nuclear waste disposal. In this work, mass spectrum with positive ions ［UO2(N3)n］+(n=0-4) as the dominant peaks generated by laser evaporation of uranium target with N2O as the carrier gas is reported. The associated quantitative calculations are carried out to explore structures and bonding interactions. The calculations show that N3 is bound to UO+2 as a radical and reveal that the bonding interaction in the whole system is found only between the first N3 ligand and uranium atom. Further localized molecular orbital analyses indicate the presence of multi-centered orbital delocalization in the system.

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

Organic single-component ferroelectrics are highly desirable for their low molecular mass, light weight, low processing temperature, and excellent film-forming properties. Organosilicon materials with a strong film-forming ability, weather resistance, nontoxicity, odorlessness, and physiological inertia are very suitable for device applications related to the human body. However, the discovery of high- T c organic single-component ferroelectrics has been very scarce, and the organosilicon ones even less so. Here, we used a chemical design strategy of H/F substitution to successfully synthesize a single-component organosilicon ferroelectric tetrakis(4-fluorophenylethynyl)silane (TFPES). Systematic characterizations and theory calculations revealed that, compared with the parent nonferroelectric tetrakis(phenylethynyl)silane, fluorination caused slight modifications of the lattice environment and intermolecular interactions, inducing a 4/ mmm F mm 2-type ferroelectric phase transition at a high T c of 475 K in TFPES. To our knowledge, this T c should be the highest among the reported organic single-component ferroelectrics, providing a wide operating temperature range for ferroelectrics. Moreover, fluorination also brought about a significant improvement in the piezoelectric performance. Combined with excellent film properties, the discovery of TFPES provides an efficient path for designing ferroelectrics suitable for biomedical and flexible electronic devices., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Multiferroic materials have attracted great interest because of their underlying new science and promising applications in data storage and mutual control devices. However, they are still very rare and highly imperative to be developed. Here, we report an organic-inorganic hybrid perovskite trimethylchloromethylammonium chromium chloride (TMCM-CrCl 3 ), showing the coexistence of magnetic and electric orderings. It displays a paraelectric-ferroelectric phase transition at 397 K with an Aizu notation of 6/ mFm , and spin-canted antiferromagnetic ordering with a Néel temperature of 4.8 K. The ferroelectricity originates from the orientational ordering of TMCM cations, and the magnetism is from the [CrCl 3 ] - framework. Remarkably, TMCM-CrCl 3 is the first experimentally confirmed divalent Cr 2+ -based multiferroic material as far as we know. A new category of hybrid multiferroic materials is pointed out in this work, and more Cr 2+ -based multiferroic materials will be expectedly developed in the future., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background: Constructing a three-dimensional (3D) model through non-invasive techniques will greatly benefit the diagnosis and treatment of otitis media. However, such a model should reflect the physiological characteristics of the middle ear; in particular, the pressure-flow responses determine the validity of the model. Objectives: A 3D model of the middle ear was constructed by digital scanning and simulation. The pressure-flow properties in the model were measured to evaluate whether the model could reflect the real middle ear under physiological and pathological conditions. Materials and methods: Computed tomography (CT) scanning data from a healthy woman were input into Mimics 20.0 to construct 3D images of the middle ear. The 3D images were treated with Ansys 15.0 for finite element mesh generation. Msc Nastran 2014 were used for the fluid-solid coupling calculations. Results: The pressure-flow rate in the model resembled a Venturi tube, namely, the pressure decreased with increasing flow velocity, especially in the Eustachian tube. In the absence of the right mastoid process, the differences in air pressure and the maximal velocity in the model were reduced. Conclusions: This numerical model based on CT images of the middle ear recapitulates the biomechanical characteristics of the real middle ear. Significance: This study provides an easy and rapid approach to constructing a middle ear model for diagnosis and treatment of otitis media.