A Family of Co^IICo^III₃ Single-Ion Magnets with Zero-Field Slow Magnetic Relaxation: Fine Tuning of Energy Barrier by Remote Substituent and Counter Cation

The synthesis, structures, and magnetic properties of a family of air-stable star-shaped Co^IICo^III₃ complexes were investigated. These complexes contain only one paramagnetic Co­(II) ion with the approximate <i>D</i>₃ coordination environment in the center and three diamagnetic Co­(III) ions in the peripheral. Magnetic studies show their slow magnetic relaxation in the absence of an applied dc field, which is characteristic behavior of single-molecule magnets (SMMs), caused by the individual Co­(II) ion with approximate <i>D</i>₃ symmetry in the center. Most importantly, it was demonstrated that the anisotropy energy barrier can be finely tuned by the periphery substituent of the ligand and the countercation. The anisotropy energy barrier can be increased significantly from 38 K to 147 K

Mn-Incorporation-Induced Phase Transition in Bottom-Up Synthesized Colloidal Sub-1-nm Ni(OH)₂ Nanosheets for Enhanced Oxygen Evolution Catalysis

Sub-1-nm structures are attractive for diverse applications owing to their unique properties compared to those of conventional nanomaterials. Transition-metal hydroxides are promising catalysts for oxygen evolution reaction (OER), yet there remains difficulty in directly fabricating these materials within the sub-1-nm regime, and the realization of their composition and phase tuning is even more challenging. Here we define a binary-soft-template-mediated colloidal synthesis of phase-selective Ni(OH)2 ultrathin nanosheets (UNSs) with 0.9 nm thickness induced by Mn incorporation. The synergistic interplay between binary components of the soft template is crucial to their formation. The unsaturated coordination environment and favorable electronic structures of these UNSs, together with in situ phase transition and active site evolution confined by the ultrathin framework, enable efficient and robust OER electrocatalysis. They exhibit a low overpotential of 309 mV at 100 mA cm–2 as well as remarkable long-term stability, representing one of the most high-performance noble-metal-free catalysts

Cobalt(II) Coordination Polymer Exhibiting Single-Ion-Magnet-Type Field-Induced Slow Relaxation Behavior

A one-dimensional cobalt­(II) coordination polymer, [Co­(btm)₂(SCN)₂·H₂O]_<i>n</i> [btm = bis­(1<i>H</i>-1,2,4-triazol-1-yl)­methane], was synthesized and magnetically characterized. The isolated slightly distorted octahedral Co^II ion displays field-induced slow relaxation with a big positive axial and a negative rhombic magnetic anisotropy (<i>D</i> = 93.9 cm^–1 and <i>E</i> = −10.5 cm^–1), and the anisotropy energy barrier is 45.4 K

Field-induced slow magnetic relaxation in a hydrogen-bonding linked Co(II) 1D supramolecular coordination polymer

<div><p>We have investigated the dynamic behaviour of the magnetization of a hydrogen-bonding linked Co(II) 1D supramolecular coordination polymer. In the structure, two different mononuclear Co(II) species are linked by O–H···N hydrogen bonding through coordinated H₂O and . Field-induced slow magnetic relaxation effect is observed and the anisotropy energy barrier is 33 K. <i>Ab initio</i> calculations reveal that Co(II) ion in [Co(bpm)₂(N₃)₂] species is uniaxial anisotropic with a negative axial zero-field splitting parameter of <i>D</i> = − 82.4 cm^− 1. The Co(II) ion in [Co(bpm)₂(H₂O)₂]²⁺ species, however, is easy-plane anisotropic with a positive <i>D</i> and negative <i>E</i> value (<i>D</i> = 46.3 cm^− 1, <i>E</i> = − 7.8 cm^− 1). This is an interesting complex in which slow magnetic relaxation stems from the combination contribution of uniaxial anisotropy and easy plane anisotropy.</p></div

Synthesis and Chiroptical Properties of Helical Polyallenes Bearing Chiral Amide Pendants

Two allene derivatives, l- and d-<i>N</i>-(1-(octylamino)-1-oxopropan-2-yl)-4-(propa-1,2-dien-1-yloxy)­benzamide (l-<b>1</b> and d-<b>1</b>), bearing chiral amide pendants were designed and synthesized. Living polymerizations of l-<b>1</b> and d-<b>1</b> with allylnickel complex as a catalyst afforded poly-l-<b>1</b>_m and poly-d-<b>1</b>_m with controlled molecular weights and narrow molecular weight distributions. These polymers were found to possess a stable helical conformation with a preferred handedness in aprotic solvents on the basis of their circular dichroism (CD) spectra and specific rotation as well as computer simulation. The helical conformation of the polymers was revealed to be stabilized by elongation of the repeating unit until the degree of the polymerization reaches 80. The slightly influence of temperature on the CD spectra of poly-l-<b>1</b>₁₀₀ in CHCl₃ indicated the helical conformation was quite stable at least in the range of 0–55 °C. Although poly-l-<b>1</b>₁₀₀ showed similar CD spectra in different aprotic solvents, remarkable decrease was observed upon the addition of protic solvents such as methanol due to the weakened hydrogen bonding interactions between the adjacent repeating units. The poly-l-<b>1</b>₁₀₀ behaves as a pH-responsive property; the helical structure of the main chain can be transformed to random coil by addition of trifluoroacetic acid to the THF solution which again switches back to helical conformation by neutralization with triethylamine. It was confirmed that the copolymerization of l-<b>1</b> and d-<b>1</b> obeyed the majority rule as supported by the nonlinear correlation between the enantiomeric excess of monomer <b>1</b> with the CD intensities of the generated copolymers. Atomic force microscope (AFM) and scanning electron microscope (SEM) studies revealed poly-l-<b>1</b>₁₀₀ self-assembled into well-defined helical fibrils with distinct handedness

Comparison of Glycemic Variability in Chinese T2DM Patient Treated with Exenatide or Insulin Glargine: A Randomized Controlled Trial

<p></p><p><b>Article full text</b></p> <p><br></p> <p>The full text of this article can be found here<b>. </b><a href="https://link.springer.com/article/10.1007/s13300-018-0412-6">https://link.springer.com/article/10.1007/s13300-018-0412-6</a></p><p></p><p></p><p> </p><p><br></p> <p><b>Provide enhanced content for this article</b></p> <p><br></p> <p>If you are an author of this publication and would like to provide additional enhanced content for your article then please contact <a href="http://www.medengine.com/Redeem/”mailto:[email protected]”"><b>[email protected]</b></a>.</p> <p><br></p> <p>The journal offers a range of additional features designed to increase visibility and readership. All features will be thoroughly peer reviewed to ensure the content is of the highest scientific standard and all features are marked as ‘peer reviewed’ to ensure readers are aware that the content has been reviewed to the same level as the articles they are being presented alongside. Moreover, all sponsorship and disclosure information is included to provide complete transparency and adherence to good publication practices. This ensures that however the content is reached the reader has a full understanding of its origin. No fees are charged for hosting additional open access content.</p> <p><br></p> <p>Other enhanced features include, but are not limited to:</p> <p><br></p> <p>• Slide decks</p> <p>• Videos and animations</p> <p>• Audio abstracts</p> <p>• Audio slides</p><br><p></p

Molecular mechanism of the tree shrew’s insensitivity to spiciness

<div><p>Spicy foods elicit a pungent or hot and painful sensation that repels almost all mammals. Here, we observe that the tree shrew (<i>Tupaia belangeri chinensis</i>), which possesses a close relationship with primates and can directly and actively consume spicy plants. Our genomic and functional analyses reveal that a single point mutation in the tree shrew’s transient receptor potential vanilloid type-1 (TRPV1) ion channel (tsV1) lowers its sensitivity to capsaicinoids, which enables the unique feeding behavior of tree shrews with regards to pungent plants. We show that strong selection for this residue in tsV1 might be driven by <i>Piper boehmeriaefolium</i>, a spicy plant that geographically overlaps with the tree shrew and produces Cap2, a capsaicin analog, in abundance. We propose that the mutation in tsV1 is a part of evolutionary adaptation that enables the tree shrew to tolerate pungency, thus widening the range of its diet for better survival.</p></div

The strong selection on site 579 is due to <i>Piper boehmeriaefolium</i>.

<p>(A) Comparison of Cap2 responses of tsV1 (solid line) and tsV1_M579T (dashed line). The holding potential was 0 mV, and test potential was at +80 and −80 mV (left panel). Concentration-response curves for tsV1 and tsV1_M579T overlapped with fits of a Hill equation (right panel). The effector concentrations for half-maximum response (average ± s.e.m) are as follows: for tsV1, 1.9 ± 0.03 mM; for tsV1_M579T, 2.34 ± 0.26 μM. The number of the tested cells is indicated. (B) Representative current traces of mV1 (solid line) and mV1_T551M (dashed line) from whole-cell recording at +80 and −80 mV (left panel). Concentration-response curves for mV1 and mV1_T551M overlapped with fits of a Hill equation (right panel). The effector concentrations for half-maximum response are as follows: for mV1, 0.74 ± 0.05 μM; for mV1_T551M, 151.4 ± 0.12 μM. The number of the tested cells is indicated. (C) Calcium imaging of mV1, tsV1, and mutants-expressing HEK293 cells challenged by Cap2 (10 μM) and ionomycin (1 mM), respectively. Scale bar, 140–2,430 AU. (D) Representative calcium fluorescence signals of mV1, tsV1, and mutants-expressing HEK293 cells were counted from representative cells (<i>n</i> = 10 cells per point). (E) Dose-response relationships of tsV1 and mutant channels containing a point replacement in site 579. The EC₅₀ values of these mutations in site 579 were as follows: 2.34 μM for tsV1_M579T; 5.46 μM for tsV1_M579S; 0.92 mM for tsV1_M579G; 1.07 mM for tsV1_M579A; and 0.83 mM for tsV1_M579V. The number of the tested cells is indicated. (F) A schematic diagram summarizing the evolutionary stress and adaptation in the tree shrew. All values are given as average ± s.e.m. The underlying data of panels A, B, D, and E can be found in <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.2004921#pbio.2004921.s009" target="_blank">S1 Data</a>. AU, arbitrary unit; HEK293 cells, human embryonic kidney cells 293; mV, mini volt; mV1, mouse TRPV1; tsV1, tree shrew TRPV1</p

Mutation on site 579 endows tsV1’s tolerance of capsaicin.

<p>(A) Representative whole-cell current traces of mV1 (shown in blue) and tsV1 (shown in red) elicited by capsaicin from whole-cell recording at +80 and −80 mV (left panel). Comparison of capsaicin responses of mV1 (blue line) and tsV1 (red line) overlapped with fits of a Hill equation (right panel). (B) Comparison of capsaicin responses of mV1, hV1, tsV1, plV1, and pV1 overlapped with fits of a Hill equation. (C) Responsiveness to capsaicin and 2APB by chimeric channels between mV1 and tsV1. (D) The amino acid sequence representing S3–S4 linker and S4 domain from tsV1 is aligned with the corresponding sequences from other 22 mammals’ TRPV1. (E) A zoomed-in view of capsaicin binding pocket of mV1. A representative configuration of docked capsaicin is shown (upper panel). Docking of capsaicin onto a zoomed-in view of S3–S4 linker and S4 domain of tsV1 (lower panel). (F) Concentration-response curves for tsV1 and channel single-point mutants overlapped with fits of a Hill equation. (G) Comparison of capsaicin responses of mV1 (blue solid line), mV1_T551V (gray dash line), and mV1_T551M (blue dash line) overlapped with fits of a Hill equation. The number of the tested cells is indicated. All values are given as average ± s.e.m. The underlying data of panels A, B, F, and G can be found in <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.2004921#pbio.2004921.s009" target="_blank">S1 Data</a>. 2APB, 2-aminoethoxydiphenyl borate; hV1, human TRPV1; mV, mini volt; mV1, mouse TRPV1; plV1, platypus TRPV1; pV1, polar bear TRPV1; TRPV1, transient receptor potential vanilloid type-1; tsV1, tree shrew TRPV1</p

Tree shrew and tsV1 show insensitivity to Cap2, a TRPV1 agonist, from <i>Piper</i> species.

<p>(A) Image of <i>Piper boehmeriaefolium</i> (Miq.) C. DC. (Piperaceae). (B) Map of South Asia showing the distribution of <i>Tupaia belangeri chinensis</i> and <i>P</i>. <i>boehmeriaefolium</i>. (C) Comparison of food consumption (apple, garlic, ginger, <i>P</i>. <i>boehmeriaefolium</i>) over 48 hours. The food consumption of wild mice (<i>Niviventer confucianus</i>) and wild tree shrews were normalized by apple consumption (<i>n</i> = 3, p ≤ 0.001). (D) Structural comparison of capsaicin (in red) and Cap2 (in blue). (E) The food intake of manufactured diet with different Cap2 concentration. All the values were normalized by the average weight of manufactured diet without Cap2 (<i>n</i> = 3, <i>p</i> ≤ 0.001). (F) Representative current traces of mV1 (blue line) and tsV1 (red line) from whole-cell recording at +80 and −80 mV. (G) The comparison of dose-response relationships for Cap2 among the tree shrew (EC₅₀ = 1.9 ± 0.03 mM, <i>n</i> = 5), human (EC₅₀ = 5.73 ± 0.05 μM, <i>n</i> = 3), mouse (EC₅₀ = 0.74 ± 0.05 μM, <i>n</i> = 5), and polar bear (EC₅₀ = 0.87 ± 0.04 μM, <i>n</i> = 6) TRPV1 channels. The number of the tested cells is indicated. All values are given as average ± s.e.m. The underlying data of panels C, E, and G can be found in <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.2004921#pbio.2004921.s009" target="_blank">S1 Data</a>. mV, mini volt; mV1, mouse TRPV1; TRPV1, transient receptor potential vanilloid type-1; tsV1, tree shrew TRPV1</p