Using Rigidity and Conjugation of Subunits to Modulate Supramolecular Topologies Constructed by Half-Sandwich Fragments.

The synthesis of supramolecular compounds with a high degree of controllability and the targeted modulation of their topological transitions pose significant challenges in situ. In this study, we have successfully constructed an array of discrete structures based on a series of bidentate pyridyl ligands (L1, L2, and L3), which were subsequently ligated with half-sandwiched (Cp*Ir fragments) building blocks. Our further investigations elucidate a strategy for coordinating the relative lengths of the bidentate ligands with the building blocks, achieving specific concentrations that drive the transformation of tetranuclear metal macrocycles into Borromean rings.

Molecular Co-Catalyst Confined within a Metallacage for Enhanced Photocatalytic CO Reduction.

The construction of structurally well-defined supramolecular hosts to accommodate catalytically active species within a cavity is a promising way to address catalyst deactivation. The resulting supramolecular catalysts can significantly improve the utilization of catalytic sites, thereby achieving a highly efficient chemical conversion. In this study, the Co-metalated phthalocyanine () was successfully confined within a tetragonal prismatic metallacage, leading to the formation of a distinctive type of supramolecular photocatalyst ().

The position of the median nerve in relation to the palmaris longus tendon at the wrist: a study of 784 MR images.

Iatrogenic injury of the median nerve has been reported after endoscopic carpal tunnel release and corticoid injection. In 784 MR images of the wrist, the position of the median nerve in relation to the palmaris longus tendon was analysed. The ulnar edge of the median nerve was found medial to the palmaris longus tendon in 14% and 36% of patients at the proximal wrist crease and entrance of the carpal tunnel, respectively, compared with 23% and 40% of patients with carpal tunnel syndrome (88 patients).

Autologous Costal Cartilage Grafting for a Large Osteochondral Lesion of the Femoral Head: A 1-Year Single-Arm Study with 2 Additional Years of Follow-up.

Background: There is currently no ideal treatment for osteochondral lesions of the femoral head (OLFH) in young patients.

Methods: We performed a 1-year single-arm study and 2 additional years of follow-up of patients with a large (defined as >3 cm 2 ) OLFH treated with insertion of autologous costal cartilage graft (ACCG) to restore femoral head congruity after lesion debridement. Twenty patients ≤40 years old who had substantial hip pain and/or dysfunction after nonoperative treatment were enrolled at a single center.

Albumin Infusion May Improve the Prognosis of Critical COVID-19 Patients with Hypoalbuminemia in the Intensive Care Unit: A Retrospective Cohort Study.

Background: The coronavirus disease 2019 (COVID-19) pandemic has caused enormous mortality worldwide. Low albumin level is a risk factor for increasing mortality among patients in the intensive care unit (ICU). This study investigated the effect of albumin infusion on critical COVID-19 patients with hypoalbuminemia.

Advantages of 3-dimensional Measurements for Supraspinatus Intramuscular Fatty Evaluation in Patients With Medium to Massive Rotator Cuff Tears: Comparison With a Single Sagittal Slice.

Background: Fatty infiltration of the rotator cuff muscles is highly related to poor outcomes after rotator cuff tears. Fat fraction (FF) based on traditional 2-dimensional measurements (2D-FF) from a single sagittal Y-view slice cannot determine intramuscular FF in the rotator cuff muscles; the newly developed 3-dimensional method (3D-FF) is supposed to precede 2D measurements for intramuscular FF evaluation in accuracy and reliability.

Purpose: (1) To measure 3D-FF and (2) to compare 3D-FF and 2D-FF in terms of quantitative values and intra- and interobserver agreement.

Feasibility of Noninvasive Diagnosis of Spinal Vascular Diseases Using Time-Resolved Angiography With Stochastic Trajectories.

To determine the feasibility of time-resolved angiography with stochastic trajectories (TWIST) in the diagnosis of spinal dural arteriovenous fistula (SDAVF) and perimedullary arteriovenous fistula (PAVF). A total of 11 negative patients with TWIST examination were retrospective analyzed and then 18 patients with suspected spinal vascular diseases underwent TWIST. For negative patients, Adamkiewicz artery (AKA), great anterior radiculomedullary vein (GARV) and anterior spinal artery (ASA) were retrospective analyzed.

Stimuli-Responsive Topological Transformation of a Molecular Borromean Ring via Controlled Oxidation of Thioether Moieties.

A Cp*-Rh based D-shaped binuclear metallacycle and a template-free molecular Borromean ring (BR) were obtained in high yield using the semi-rigid thioether dipyridyl ligand 1,4-bis[(pyridin-4-ylthio)methyl]benzene (Bptmb). The topological transformation from a binuclear metallacycle and a BR to tetranuclear metallacycles was realized via the controlled oxidation of thioethers. The strategy used in this work can be regarded as a new form of stimuli-responsive post-synthesis modification (PSM).

Self-assembly and guest-induced disassembly of triply interlocked [2]catenanes.

Two fascinating triply interlocked [2]catenanes and one simple triangular prism metallacage were constructed by tuning the widths of the organometallic dinuclear building blocks. Notably, the interlocked architectures were disassembled in the presence of large aromatic molecules to form their corresponding monomeric host-guest complexes.

Selective colorimetric detection of copper (II) by a protein-based nanoprobe.

In this work, we report a novel protein-based nanoprobe (PNP) that can be employed for quantitative analysis of Cu in pure water medium and real samples. Structurally, the proposed nanoprobe comprises a biofriendly protein (hen egg-white lysozyme (HEWL)) and a Cu-specific chromogenic agent, where HEWL acts as a nanocarrier encapsulating a structurally tailored rhodamine B derivate. The resulting PNP exhibits a hydrodynamic diameter of ~ 106 nm and efficiently disperses in water, enabling the detection of Cu in pure aqueous systems without the aid of any organic co-solvents.

Facile preparation of sulfonated biochar for highly efficient removal of toxic Pb(II) and Cd(II) from wastewater.

Biochar is deemed as the ideal material for the effective removal of heavy metals in wastewater treatment. Herein, we developed a facile one-step solvothermal method for the preparation of sulfonated biochar (SBC) from Axonopus compressus under a low-temperature condition. FTIR and XPS analysis demonstrate that plenty of -OH, -COOH and -SOH moieties are generated on the surface of SBC during the sulfonation process.

A new supramolecular catalytic system: the self-assembly of Rh8 cage host anthracene molecules for [4 + 4] cycloaddition induced by UV irradiation.

The supramolecular assembly, used as a molecular reactor, is of great significance in host-guest chemistry. In this work, we used a tetratopic pyridyl ligand as a building block to hierarchically combine a slightly twisted cuboid with half-sandwich rhodium fragments. The cuboid directionally self-assembled hydrophobic pockets that can encapsulate conjugated molecules like anthracene (ANT) as guests in solutions, by supramolecular interactions including hydrogen bonding and hydrophobic interactions.

Electrocatalytic oxygen evolution with a cobalt complex.

The development of an earth-abundant, first-row water oxidation catalyst that operates at a high TOF and a low overpotential remains a fundamental chemical challenge. Cobalt complexes are important members of water oxidation catalysts. Herein, we report a cobalt-based robust homogeneous water oxidation catalyst, which can electrocatalyze water oxidation at a high pH and a low overpotential (η = 520 mV) in phosphate buffer.

A new copper species based on an azo-compound utilized as a homogeneous catalyst for water oxidation.

A new azo-complex [(L)Cu(II)(NO3)] [L = (E)-3-(pyridin-2-yldiazenyl)naphthalen-2-ol (HL)], was prepared via a one-pot synthetic method at 60 °C and was structurally characterized by IR, EA, PXRD and single crystal X-ray diffraction. In addition, TGA studies indicated that the complex was stable in air. The redox properties were determined by cyclic voltammetry, which revealed that the complex could be utilized as a catalyst for water oxidation under mild conditions.

Anion-directed self-assembly of two half-sandwich ruthenium-based metallamacrocycles as catalysts for water oxidation.

The binuclear [η(6) -(cymene)Ru(L)]2 (OTf)2 (TfO(-) =trifluoromethanesulfonate) and tetranuclear [η(6) -(cymene)Ru(L)]4 (NO3 )4 metallacycles were prepared by treating the pyridyl-substituted 8-hydroxyquinoline ligand (E)-2-[2-(pyridin-3-yl)vinyl]quinolin-8-ol (HL) with [(p-cymene)Ru(μ-Cl)Cl]2 in the presence of AgOTf or AgNO3 . The molecular structures of these complexes were confirmed by single-crystal X-ray diffraction, which revealed that both complexes have macrocycle frameworks induced by the TfO(-) and NO3 (-) counteranions, respectively. The electrochemical properties of the two metallacycles were investigated by cyclic voltammetry, which showed that they have great potential as catalysts for water oxidation.

Water oxidation catalysts and pH sensors based on azo-conjugated iridium/rhodium motifs.

Herein we report the molecular structures and electronic properties of ionic, hydrophobic half-sandwich complexes with formula [η(5)-Cp*Ir(L)(Cl)](OTf) (), [η(5)-Cp*Rh(L)(Cl)](OTf) (), [η(5)-Cp*Ir(L)(H2O)](OTf)2 () and [η(5)-Cp*Rh(L)(H2O)](OTf)2 (), where L is 1-(2-pyridylazo)-2-naphthol. The electrochemical properties of these complexes have been investigated, and they displayed good electronic properties for use as water oxidation catalysts. Interestingly, the color of their solutions is unambiguously transformed from brown to green at pH = 12; the color changes of , and are especially apparent.

Azo-conjugated half-sandwich Rh/Ru complexes for homogeneous water-oxidation catalysis.

Herein we report the molecular structures and electronic properties of ionic, hydrophobic, half-sandwich complexes of the formula [η(5)-Cp*Rh(L)(MeOH)] (1) and [η(6)-CyRu(L)(H2O)] (2), where L is azo-dye compound of (p-(2-hydroxy-1-naphthylazo)benzenesulfonic acid sodium salt). Both these complexes have been investigated electrochemically and found to display good electronic properties for use as water-oxidation catalysts potentially.

Iridium-mediated regioselective B-H/C-H activation of carborane cage: a facile synthetic route to metallacycles with a carborane backbone.

One-pot reactions of carborane carboxylic acids (L), [Cp*IrCl2]2, and silver salt are reported, which lead to regioselective B-H or C-H bond activation at ambient temperature in good yields. This process is demonstrated for three carborane (o-, m-, p-) dicarboxylates, and metal-mediated B-H functionalization of a p-carborane derivative is accomplished for the first time. Two metal-induced self-assembly routes to tetra-nuclear metallacycles 3 and 5 were performed through B(4, 7)/H and B(2, 10)/H activation, respectively, and the two metallacycles were found to be stable and to exist in solution as discrete complexes.

Stability analysis and synchronization in discrete-time complex networks with delayed coupling.

A new network of coupled maps is proposed in which the connections between units involve no delays but the intra-neural communication does, whereas in the work of Atay et al. [Phys. Rev.

Construction of tetranuclear macrocycles through C-H activation and structural transformation induced by [2+2] photocycloaddition reaction.

A series of binuclear complexes [{Cp*Ir(OOCCH(2)COO)}(2)(pyrazine)] (1b), [{Cp*Ir(OOCCH(2)COO)}(2)(bpy)] (2b; bpy=4,4'-bipyridine), [{Cp*Ir(OOCCH(2)COO)}(2)(bpe)] (3b; bpe=trans-1,2-bis(4-pyridyl)ethylene) and tetranuclear metallamacrocycles [{(Cp*Ir)(2)(OOC-C=C-COO)(pyrazine)}(2)] (1c), [{(Cp*Ir)(2)(OOC-C=C-COO)(bpy)}(2)] (2c), [{(Cp*Ir)(2)(OOC-C=C-COO)(bpe)}(2)] (3c), and [{(Cp*Ir)(2)[OOC(H(3)C(6))-N=N-(C(6)H(3))COO](pyrazine)}(2)] (1d), [{(Cp*Ir)(2)[OOC(H(3)C(6))-N=N-(C(6)H(3))COO](bpy)}(2)] (2d), [{(Cp*Ir)(2)[OOC(H(3)C(6))-N=N-(C(6)H(3))COO](bpe)}(2)] (3d) were formed by reactions of 1a-3a {[(Cp*Ir)(2)(pyrazine)Cl(2)] (1a), [(Cp*Ir)(2)(bpy)Cl(2)] (2a), and [(Cp*Ir)(2)(bpe)Cl(2)] (3a)} with malonic acid, fumaric acid, or H(2)ADB (azobenzene-4,4'-chcarboxylic acid), respectively, under mild conditions. The metallamacrocycles were directly self-assembled by activation of C-H bonds from dicarboxylic acids. Interestingly, after exposure to UV/Vis light, 3c was converted to [2+2] cycloaddition complex 4.

Stepwise formation of organometallic macrocycles, prisms and boxes from Ir, Rh and Ru-based half-sandwich units.

Over the past decade, supramolecular compounds with organometallic Ir, Rh, Ru based half-sandwich complexes have received considerable attention as materials with a variety of potential applications. The major emphasis of this tutorial review lies on the self-assembly of such organometallic half-sandwich molecular rectangles, prisms and cages with half-sandwich corners and two different rigid bifunctional ligands using an approach of stepwise construction. Synthetic methods and the structural and functional properties of the target complexes are discussed in detail.

A homochiral nanotubular crystalline framework of metallomacrocycles for enantioselective recognition and separation.

A highly ordered homochiral nanotubular crystalline framework was assembled from a hexameric Zn6L6metallaycle that was built from metallosalen ZnL units (H2L = (R,R)-(-)-N,N'-Bis(3-tert-butyl-5-(4- pyridyl) salicylidene)-1,2-diaminocyclohexane) by the complementary coordination of the pyridyl groups to the metal centers. Chiral channels and hydrophobic functionality presented by this structure make it an excellent host to recognize and separate racemic alcohols with high enantioselectivity (up to 99.5%).