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This work reports a combined experimental and theoretical study on the new dibenzo-1,5-ditellurocine 2-Te in order to get an overview on the parameters controlling conformational change and to explain the differences with sulfur and selenium analogues. The preference of the boat conformer over the chair one is revealed by DFT calculations. For 2-Te, a ΔG value of about 3 kJ/mol was calculated, close to the value measured by NMR (5 kJ/mol). However, DFT calculations with implicit solvation effects could not clearly establish the presence of an intramolecular Te…HC noncovalent interaction (NCI), as observed in the solid state. The Independent Gradient Model (IGM) methodology discloses an existent but probably not sufficiently discriminating Te…HC NCI. It also confirms that van der Waals interactions between phenyl rings is a source of stabilization of the boat conformer. Furthermore, electrostatic potential analysis suggests that chalcogen bonds between Te σ-holes and solvent might play an important role.Inspired by the sophisticated design of biological systems, interest in soft intelligent actuators has increased significantly in recent years, providing attractive strategies for the design of elaborate soft mechanical systems. For the construction of those soft actuators, carbon nanomaterials were extensively and successfully explored for the properties of highly conductive, electrothermal, and photothermal conversion. This review aims to trace the recent achievements for the material and structural design as well as the general mechanisms of the soft actuators, paying particular attention to the contribution of carbon nanomaterials resulted from their diversified interplaying properties, which realized the flexible and dexterous deformation responding to various environmental stimuli, including light, electricity and humidity. The properties and mechanisms of soft actuators are summarized and the potential for future applications and research are presented.DNA nanostructures, that show sequence programmable responsiveness to intracellular signals, have been explored as potential candidates of artificial dynamic functional structures in living cells. Recently, we developed a series of intracellular signals responding DNA nanostructures in living cells to perform a special mission. In this review, the developed DNA nanostructures and their dynamic transformation properties are summarized and discussed. The DNA nanostructures are generally categorized into DNA-inorganic nanomaterials and DNA-organic nanomaterials depending on the composition. At the end of this review, the challenges and prospects on instructing dynamic DNA nanostructures in living cells are discussed. We believe that this review will contribute to the further development of stimuli-responsive nanomaterials, which is of great potential in biomedical applications.There has never been a stronger call for authenticity in health professions education than this moment in time. The health inequities laid bare by the COVID-19 syndemic (a concept that describes the clustering of SARS-CoV-2 infection and disease by political, social, and economic factors) compels health professions educators to learn how to best engage in, sustain, and deepen conversations on diversity, equity, and inclusion (DEI) within our learning environments. Health professions curricula should address such concerns through explicit faculty training programs in dialogue models of communication. In this commentary, I propose that medical improv can help refocus health professions training to the humanistic values of empathy for others and respect for multiple viewpoints. Medical improv refers to teaching methods that adapt improvisation principles and exercises to enhance professional competencies in the health professions, such as communication. I describe a training series implemented at one institution to prepare faculty facilitators to engage in conversations about DEI in a discussion-based core course on the social determinants of health for first year medical students called "Humanity in Medicine." Key elements of dialogue training, including examinations of identity and positionality, caretaking and team-making, and conversations with a skeptic, are viewed through the lens of improv exercises as a pedagogy in communication. find more I report on facilitator and medical students' positive response to facilitator training and the Humanity in Medicine course. Potential next steps towards a formal evaluation of the method, and outcomes assessments of the use of improv in health professions training are discussed.During laparoscopic surgery, the Veress needle is commonly used in pneumoperitoneum establishment. Precise placement of the Veress needle is still a challenge for the surgeon. In this study, a computer-aided endoscopic optical coherence tomography (OCT) system was developed to effectively and safely guide Veress needle insertion. This endoscopic system was tested by imaging subcutaneous fat, muscle, abdominal space, and the small intestine from swine samples to simulate the surgical process, including the situation with small intestine injury. Each tissue layer was visualized in OCT images with unique features and subsequently used to develop a system for automatic localization of the Veress needle tip by identifying tissue layers (or spaces) and estimating the needle-to-tissue distance. We used convolutional neural networks (CNNs) in automatic tissue classification and distance estimation. The average testing accuracy in tissue classification was 98.53 ± 0.39%, and the average testing relative error in distance estimation reached 4.42 ± 0.56% (36.09 ± 4.92 μm).The synthesis of hybrid platinum materials is fundamental to enable alkaline water electrolysis for cost-effective H2 generation. In this work, we have used a galvanostatic method to co-deposit PtNi films onto polycrystalline gold. The surface concentrations of Ni (ΓNi ) and Pt (ΓPt ) were calculated from electrochemical measurements; the ΓPt /ΓNi ratio and electrocatalytic activity of these materials towards hydrogen evolution reaction (HER) in 1 M KOH show a strong dependence on the current density pulse applied during the electrodeposition. Analysis of the Tafel parameters hints that, on these deposits, HER proceeds through a Volmer-Heyrovsky mechanism. The galvanostatically deposited PtNi layers present a high current output per Pt gram, 3199 A gPt -1 , which is significantly larger compared to other PtNi-based materials obtained by more extended and more complex synthesis methods.Invited for this month's cover are the groups of Célia Fonseca Guerra at the Vrije Universiteit Amsterdam and Leiden University, Giampaolo Barone from the Università degli Studi di Palermo, and F. Matthias Bickelhaupt at Vrije Universiteit Amsterdam and Radboud University Nijmegen. The cover picture shows the four primary interaction components (hydrogen bonding, cross-terms, base stacking, and solvation) that determine the stability of B-DNA duplexes. Quantum chemical analyses identify an interplay between the stabilizing hydrogen bonds between nucleotides that drive the formation of the DNA double-strand, and the destabilizing loss of stacking interactions within individual strands combined with partial desolvation. The sequence-dependence in the duplex stability originates mainly from the cross-terms, which can be attractive or repulsive. Read the full text of their Research Article at 10.1002/open.202100231.A high-surface-area Ce doped mullite YMn2 O5 was developed via a facile hydrothermal approach, which exhibited higher catalytic activity with a long thermal stability towards propane oxidation in regards to pristine mullite YMn2 O5 . T90 (the temperature at 90 % conversion of reactant) of propane over the mixed oxides is ∼40 °C lower than that over pristine YMn2 O5 mullite (147 m2 /g). The complete oxidation temperature occurs at as low as 225 °C (1000 ppm C3 H8 and 10 % O2 balanced with N2 , WHSV=30,000 mL/g h). Notably, the mixed oxides maintain superior catalytic stability at 250 °C for 120 h without noticeable loss in the activity. Fundamentally, the remarkable performance stems from the abundant oxygen defects caused by the lattice mismatch between CeO2 and YMn2 O5 , which is conducive to the gas phase oxygen adsorption and activation, thereby enhancing the low temperature catalytic activity of the material. In addition, the CeO2 on the catalyst's surface acts as an oxygen reservoir and provides additional adsorption sites for propane to promote the oxidation reaction. In situ DRIFTS results indicates that the dissociation of acrylate could be the key step for propane oxidation since acrylate is more difficult to decompose and desorb than formate and acetate. These findings revealed the roles of ceria on mullite oxides for propane oxidation activity.Nucleic acid quadruplexes are proposed to play a role in the regulation of gene expression, are often present in aptamers selected for specific binding functions and have potential applications in medicine and biotechnology. Therefore, understanding their structure and thermodynamic properties and designing highly stable quadruplexes is desirable for a variety of applications. Here, we evaluate DNA→RNA substitutions in the context of a monomolecular, antiparallel quadruplex, the thrombin-binding aptamer (TBA, GGTTGGTGTGGTTGG) in the presence of either K+ or Sr2+ . TBA predominantly folds into a chair-type configuration containing two G-tetrads, with G residues in both syn and anti conformation. All chimeras with DNA→RNA substitutions (G→g) at G residues requiring the syn conformation demonstrated strong destabilization. In contrast, G→g substitutions at Gs with anti conformation increased stability without affecting the monomolecular chair-type topology. None of the DNA→RNA substitutions in loop positions affected the quadruplex topology; however, these substitutions varied widely in their stabilizing or destabilizing effects in an unpredictable manner. This analysis allowed us to design a chimeric DNA/RNA TBA construct that demonstrated substantially improved stability relative to the all-DNA construct. These results have implications for a variety of quadruplex-based applications including for the design of dynamic nanomachines.

Both fine-needle aspiration biopsy (FNAB) and frozen section (FS) examination are reliable methods for assessing cervical lymph node (level II-V) metastasis (LNM) in papillary thyroid carcinoma (PTC). Our goal was to compare the diagnostic accuracy of FNAB and FS in clinically positive neck (cN+) PTC patients.

Altogether, 264 lymph node samples from 220 patients were prospectively enrolled. Samples were assessed by FNAB cytology (FNAB-C), thyroglobulin (Tg) FNAB needle wash testing (FNAB-Tg), and FS simultaneously. Diagnostic performance of the different methods were analyzed by the Chi-square test.

The sensitivity and specificity of FNAB-C alone in predicting LNM was 87.4% and 85.7%, respectively. Combined with FNAB-Tg, the sensitivity and specificity of FNAB-C increased to 98.9% and 81.6%, respectively. The sensitivity and specificity of FS in predicting LNM was 92.4% and 81.1%, respectively. FNAB-C and FNAB-Tg had better sensitivity than FS when applied to solid lymph nodes, and comparable sensitivity when applied to cystic and cystic-solid lymph nodes.