Assuming that there exist at least two fermionic parameters, the classical N = 1 supersymmetric Korteweg-de Vries (SKdV) system can be transformed to some coupled bosonic systems. The boson fields in the bosonized SKdV (BSKdV) systems are defined on even Grassmann algebra. Due to the intrusion of other Grassmann parameters, the BSKdV systems are different from the usual non-suppersymmetric integrable systems, and many more abundant solution structures can be unearthed. With the help of the singularity analysis, the Painlevé property of the BSKdV system is proved and a Bäcklund transformation (BT) is found. The BT related nonlocal symmetry, we call it as residual symmetry, is used to find symmetry reduction solutions of the BSKdV system. Hinted from the symmetry reduction solutions, a more generalized but much simpler method is established to find exact solutions of the BSKdV and then the SKdV systems, which actually can be applied to any fermionic systems.

Scheme 1. The structures of closo-carborane-functionalized facial and meridional iridium(III) complexes.

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Some simple special Bäcklund transformation theorems are proposed and utilized to obtain exact solutions for the (2 + 1)-dimensional Euler equation. It is found that the (2 + 1)-dimensional Euler equation possesses abundant soliton or solitary wave structures, conoid periodic wave structures and the quasi-periodic Bessel wave structures on account of the arbitrary functions in its solutions. Moreover, all solutions of the arbitrary two dimensional nonlinear Poisson equation can be used to construct exact solutions of the (2 + 1)-dimensional Euler equation.

2-Thienylpyridyl iridium(III) complexes containing an o-, m-, or p-carboranylvinyl-2,2'-bipyridine ligand and various counteranions (denoted o-PF6, m-BF4, m-PF6, m-SbF6, m-ClO4, m-OTf, m-NO3, m-BPh4, m-F, m-Cl, and p-PF6) were synthesized by using C-formyl carboranes as starting materials. The solid-state structures of o-PF6, m-PF6, m-ClO4, and m-BF4 showed that the cations form twisted cavities in which the anions are fixed by multiple hydrogen bonds. Anion-hydrogen interactions were investigated for nine m-carborane-based complexes with different counteranions. All carborane-based iridium(III) complexes show similar phosphorescence yields in solution but significantly different emission in the solid state. Anion-exchange titration and theoretical calculations revealed the relationships between structures and optical properties. The size of the anion and C-H⋅⋅⋅X anion-hydrogen bonds strongly influence the phosphorescence quantum yield in the solid state. In particular, the Ccar-H⋅⋅⋅X hydrogen bonds between the carboranyl unit and the anion play an important role in solid-state phosphorescence. Complex p-PF6 was successfully applied in phosphorescence-lifetime bioimaging owing to its low toxicity and near-infrared emission.

Dedicated to Professor Xiaozeng You on the occasion of his 80th birthdayIcosahedral closo-carboranes including 1,2-, 1,7-, and 1,12-C 2 B 10 H 12 (that is, o-, m-, and p-carborane) have been intensively investigated for decades owing to their unique 3D pseudo aromatic geometric structures and push-pull electronic properties.[1] Recently, more attention has been paid to optoelectronic properties of carborane-based materials.[2] However, the effects of carborane cage itself on photophysical properties of materials still need further investigation, especially for o-carborane derivatives, which possess an unusual C À C bond (in the range of 1.62-2.15 for the bond distance) [3] and usually quench luminescence.Better understanding of this phenomenon is important to guide further molecular design of carborane-containing luminescent materials. On the other hand, nido-carboranefunctionalized luminescent compounds are less studied [4] in comparison to closo-carborane-based derivatives, despite hydrophilic nido-carborane derivatives being promising candidates for biological applications such as in bioimaging.In the last decade, phosphorescent iridium(III) complexes have been widely used in organic light-emitting diodes (OLEDs), [5] chemosensors, [6] and bioimaging [7] owing to their stable chemical structure, high luminescent efficiency, and tunable excitation and emission wavelength over the whole visible range. However, few carborane-based phosphorescent iridium(III) complexes have been reported. [8] It is anticipated that introduction of carborane cages into phosphorescent iridium(III) complexes may further improve the photophysical properties of these complexes and allow better understanding the roles of carborane groups. As such, we chose the well-studied homoleptic triply cyclometalated phosphorescent iridium(III) complexes [Ir(ppy) 3 ][9] (ppy = 2-phenylpyridine) as control compounds and synthesized a series of facial and meridional iridium(III) complexes containing o-, m-, or p-carboranyl units in the cyclometalated C^N ligand, denoted as fac-o, fac-m, and fac-p for facial complexes and mer-o, mer-m, and mer-p for meridional complexes (Scheme 1). The results demonstrate that introduction of m-and p-carborane cages can improve phosphorescence efficiency (F P ) of both facial and meridional structures. The luminescent efficiency of the o-carborane derivative fac-o exhibits solvent-or media-dependence, which is closely related to dielectric constant (e) of media as the specific C À C bond of o-carborane is involved in excited state and highly sensible to media. A new phosphorescent iridium-(III) complex containing nido-o-carborane cages has been prepared as well, which possesses stable chemical structure, excellent water solubility, high phosphorescence efficiency (absolute F P = 0.36 in aqueous solution), and a long emission lifetime, thus has been successfully applied in cellular bioimaging.All of the carborane-functionalized cyclometalated ligands (R-ppy) were prepared through an efficient SuzukiMiyaura cross-co...

Abstract. Accumulation of unfolded proteins in the endoplasmic reticulum (ER) induces ER stress which is observed in many human diseases, including breast cancer. Cellular adaptation to ER stress is mediated by the unfolded protein response (UPR), which aims at restoring ER homeostasis. Higher levels of GRP78 expression indicates constitutive activation of the UPR in breast cancer leading to breast cancer cells that are relatively resistant to ER stress-induced apoptosis. Tunicamycin (TM), an ER stress inducer, constitutively activates the mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase (ERK), and (MEK)/ERK pathway which plays a role in upregulation of GRP78 by ER stress in that inhibition of MEK by U0126 reduces the levels of GRP78 and blocks its upregulation by TM. Inhibition of the MEK/ERK pathway by U0126 sensitizes breast cancer cells to TM-induced apoptosis. Inhibition of GRP78 by siRNA knockdown enhances TM-and U0126-induced apoptosis in breast cancer cells. This sensitization of breast cancer cells to TM-induced apoptosis by inhibition of MEK/ERK and GRP78 is caspase-dependent, at least in part, by activation of caspase-4. These results seem to indicate that GRP78 has potential as a chemotherapeutical target and have important implications for new treatment strategies in breast cancer by combination with agents that induce ER stress with inhibitors of the MEK/ERK pathway.