Quantum and Braided Lie Algebras

We introduce the notion of a braided Lie algebra consisting of a finite-dimensional vector space \CL equipped with a bracket $[\ ,\ ]:\CL\tens\CL\to \CL$and a Yang-Baxter operator$\Psi:\CL\tens\CL\to \CL\tens\CL$obeying some axioms. We show that such an object has an enveloping braided-bialgebra$U(\CL)$. We show that every generic$R$-matrix leads to such a braided Lie algebra with$[\ ,\ ]$given by structure constants$c^{IJ}{}_K$determined from$R$. In this case$U(\CL)=B(R)$the braided matrices introduced previously. We also introduce the basic theory of these braided Lie algebras, including the natural right-regular action of a braided-Lie algebra$\CL$by braided vector fields, the braided-Killing form and the quadratic Casimir associated to$\CL$. These constructions recover the relevant notions for usual, colour and super-Lie algebras as special cases. In addition, the standard quantum deformations$U_q(g)$are understood as the enveloping algebras of such underlying braided Lie algebras with$[\ ,\ ]$on$\CL\subset U_q(g)$ given by the quantum adjoint action.Comment: 56 page

Equivalence of quotient Hilbert modules

Let \cl{M} be a Hilbert module of holomorphic functions over a natural function algebra $\mathcal{A}(\Omega)$, where \Omega \subseteq \bb{C}^m is a bounded domain. Let \cl{M}_0\subseteq \cl{M} be the submodule of functions vanishing to order $k$ on a hypersurface \cl{Z} \subseteq \Omega. We describe a method, which in principle may be used, to construct a set of complete unitary invariants for quotient modules \cl{Q}=\cl{M} \ominus \cl{M}_0. The invariants are given explicitly in the particular case of $k = 2$.Comment: 11 page

Effects of aminoperimidine on electrolyte transport across amphibian skin

The effect of aminoperimidine (AP)on transepithelial Na+ transport and Cl- conductance (G(Cl)) of isolated amphibian skin (Bufo viridis and Rana esculenta) was analyzed using transepithelial and intracellular electrophysiological techniques. AP, applied at concentrations between 30 and 100 mu M from the mucosal side, stimulated Na+ transport rapidly and reversibly by more than 30% of the control value due to an increase in apical membrane Na+ permeability. Influence of AP on basolateral membrane conductance and effective driving force for Na+ were negligible. Voltage-activated G(Cl) of toad skin, but not the resting, deactivated conductance, as well as spontaneously high G(Cl) in frog skin was rapidly inhibited by AP in a concentration-dependent manner. The half-maximal inhibitory concentration of 20 mu M is the highest hithero reported inhibitory power for G(Cl) in amphibian skin. The effect of AP on G(Cl) was slowly and incompletely reversible even after brief exposure to the agent. Serosal application of AP had similar, albeit delayed effects on both Nai and Cl- transport. AP did not interfere with the Cl- pathway after it was opened by 100-300 mu M CPT-cAMP, a membrane-permeable, nonhydrolyzed analogue of cAMP. Inhibition of the voltage-activated G(Cl) by AP was attenuated or missing when AP was applied during voltage perturbation to serosa-positive potentials. Since AP is positively charged at physiological pH, it suggests that the affected site is located inside the Cl- pathway at a certain distance from the external surface. AP affects then the Na+ and Cl- transport pathways independent of each other. The nature of chemical interference with AP, which is responsible for the influence on the transport of Na+ and Cl-, remains to be elucidated

Establishing a rapid and effective method for screening salt tolerance in soybean

Chlorine (Cl) toxicity has been recognized as a constraint for soybean production. Although the use of a Cl-tolerant crop easily solves the problem, current screening methodologies for Cl tolerance are often ineffective because of inadequate means of detecting and measuring plant response to salinity. In order to facilitate the evaluation process and selection of Cl-tolerant genotypes, a study was conducted to develop a rapid and effective method for screening Cl tolerance in soybean. Seeds of five soybean cultivars, each representing either the includer or excluder genotype to salt stress, were grown in a greenhouse in two different growing media (potting mix or sandy loam) with four different concentrations of sodium chloride (NaCl) solutions. Visual symptoms of Cl toxicity were rated on a 1 to 6 scale (1 as healthy and 6 as dead), and the score was compared with relative shoot/ root dry weight and Cl concentration in shoot/root to corroborate the accuracy of the visual ratings. Reduced dry weight was associated with higher Cl concentrations in both root and shoot tissues. The optimal NaCl concentration for screening was determined as 120 mM NaCl since it effectively differentiated excluders from includers. There were negative, significant correlations between relative shoot dry weight and Cl concentration in shoot tissue (r = -0.91 p = 0.05), and Cl concentration in shoot was also significantly correlated with visual rating score (r = 0.79 p = 0.05). The presented methodology is simple, rapid, and effective for screening for salt tolerance in soybean

Characterization of constitutive and acid-induced outwardly rectifying chloride currents in immortalized mouse distal tubular cells

Thiazides block Na+ reabsorption while enhancing Ca2 + reabsorption in the kidney. As previously demonstrated in immortalized mouse DCT (MDCT) cells, chlorothiazide application induced a robust plasma membrane hyperpolarization, which increased Ca2 + uptake. This essential thiazide-induced hyperpolarization was prevented by the Cl− channel inhibitor 5-Nitro-2-(3-phenylpropylamino) benzoic acid (NPPB), implicating NPPB-sensitive Cl− channels, however the nature of these Cl− channels has been rarely described in the literature. Here we show that MDCT cells express a dominant, outwardly rectifying Cl− current at extracellular pH 7.4. This constitutive Cl− current was more permeable to larger anions (Eisenman sequence I; I− > Br− ≥ Cl−) and was substantially inhibited by > 100 mM [Ca2 +]o, which distinguished it from ClC-K2/Barttin. Moreover, the constitutive Cl− current was blocked by NPPB, along with other Cl− channel inhibitors (DIDS, FFA). Subjecting the MDCT cells to an acidic extracellular solution (pH < 5.5) induced a substantially larger outwardly rectifying NPPB-sensitive Cl− current. This acid-induced Cl− current was also anion permeable (I− > Br− > Cl−), but was distinguished from the constitutive Cl− current by its rectification characteristics, ion sensitivities, and response to FFA. In addition, we have identified similar outwardly rectifying and acid-sensitive currents in immortalized cells from the inner medullary collecting duct (mIMCD-3 cells). Expression of an acid-induced Cl− current would be particularly relevant in the acidic IMCD (pH < 5.5). To our knowledge, the properties of these Cl− currents are unique and provide the mechanisms to account for the Cl− efflux previously speculated to be present in MDCT cells

Synthesis and Characterization of the k^2-acac-O,O Complex Os_(IV)(acac)_2PhCl and Study of CH Activation with Benzene

We have synthesized and fully characterized the air-stable complex (κ^2-acac-O,O)2Os^(IV)(Ph)Cl (Cl-1-Ph; acac-O,O = acetylacetonate), which reacts with C_6D_6 to generate Cl-1-Ph-d_5 in high yield and catalyzes the H/D exchange reaction between benzene and toluene-d_8 upon heating to 140 °C. To our knowledge, this is the first example of stoichiometric and catalytic, homogeneous, intermolecular CH activation of arenes by a discrete Os complex. The reactions show extended induction periods. DFT studies of Cl-1-Ph and cis-(κ^2-acac-O,O)_2Os^(III)(C_6H_5)(C_6D_6) (cis-(C_6D_6)-2-Ph) found a mechanism involving CH activation by traces of Os(III) and Cl atom transfer between Cl-1-Ph and cis-(C_6D_6)-2-Ph. Experimental data showing that addition of reductants eliminates the induction periods suggest that CH activation occurs from an oxidation state lower than Os^(IV), consistent with the DFT predictions. Consistent with a Cl atom transfer mechanism, the triflate analogue of Cl-1-Ph, OTf-1-Ph, does not undergo a stoichiometric or catalytic reaction with C_6D_6

Threshold photoelectron photoion coincidence spectroscopy of trichloroethene and tetrachloroethene

The threshold photoelectron, the threshold photoelectron photoion coincidence and ion breakdown spectra of trichloroethene and tetrachloroethene have been recorded from 9 – 22 eV. Comparisons with the equivalent data for the three dichloroethene molecules and theoretical calculations highlight the nature of the orbitals involved during photoionisation in this energy range. The ground electronic state of C$_2$HCl$_3^+$ (C$_2$Cl$_4^+$) is bound, with excited valence states dissociating to C$_2$HCl$_2^+$ (C$_2$Cl$_3^+$) and C$_2$HCl$^+$ (C$_2$Cl$_2^+$). Appearance energies suggest that C$_2$HCl$^+$ forms from C$_2$HCl$_3^+$ by loss of two chlorine atoms, whereas C$_2$Cl$_2^+$ forms from C$_2$Cl$_4^+$ by loss of a Cl$_2$ molecule. The translational kinetic energy release into C$_2$HCl$_2^+$ (C$_2$Cl$_3^+$) + Cl is determined as a function of energy. In both cases, the fraction of the available energy released into translational energy of the two products decreases as the photon energy increases

Herschel observations of interstellar chloronium. II - Detections toward G29.96-0.02, W49N, W51, and W3(OH), and determinations of the ortho-to-para and 35^{35}Cl/37^{37}Cl isotopic ratios

We report additional detections of the chloronium molecular ion, H$_2$Cl$^+$, toward four bright submillimeter continuum sources: G29.96, W49N, W51, and W3(OH). With the use of the HIFI instrument on the Herschel Space Observatory, we observed the $2_{12}-1_{01}$ transition of ortho-H$_2^{35}$Cl$^+$ at 781.627 GHz in absorption toward all four sources. Much of the detected absorption arises in diffuse foreground clouds that are unassociated with the background continuum sources and in which our best estimates of the $N({\rm H_2Cl^+})/N({\rm H})$ ratio lie in the range $(0.9 - 4.8) \times 10^{-9}$. These chloronium abundances relative to atomic hydrogen can exceed the predictions of current astrochemical models by up to a factor of 5. Toward W49N, we have also detected the $2_{12}-1_{01}$ transition of ortho-H$_2^{37}$Cl$^+$ at 780.053 GHz and the $1_{11}-0_{00}$ transition of para-H$_2^{35}$Cl$^+$ at 485.418 GHz. These observations imply $\rm H_2^{35}Cl^+/H_2^{37}Cl^+$ column density ratios that are consistent with the solar system $^{35}$Cl/$^{37}$Cl isotopic ratio of 3.1, and chloronium ortho-to-para ratios consistent with 3, the ratio of spin statistical weights.Comment: 31 pages, including 7 figures. Accepted for publication in the Ap