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Accumulation of mutant proteins is a major cause of many diseases (collectively called proteopathies), and lowering the level of these proteins can be useful for treatment of these diseases. We hypothesized that compounds that interact with both the autophagosome protein microtubule-associated protein 1A/1B light chain 3 (LC3).sup.1 and the disease-causing protein may target the latter for autophagic clearance. Mutant huntingtin protein (mHTT) contains an expanded polyglutamine (polyQ) tract and causes Huntington's disease, an incurable neurodegenerative disorder.sup.2. Here, using small-molecule-microarray-based screening, we identified four compounds that interact with both LC3 and mHTT, but not with the wild-type HTT protein. Some of these compounds targeted mHTT to autophagosomes, reduced mHTT levels in an allele-selective manner, and rescued disease-relevant phenotypes in cells and in vivo in fly and mouse models of Huntington's disease. We further show that these compounds interact with the expanded polyQ stretch and could lower the level of mutant ataxin-3 (ATXN3), another disease-causing protein with an expanded polyQ tract.sup.3. This study presents candidate compounds for lowering mHTT and potentially other disease-causing proteins with polyQ expansions, demonstrating the concept of lowering levels of disease-causing proteins using autophagosome-tethering compounds. Compounds that interact with mutant huntingtin and an autophagosomal protein are able to reduce cellular levels of mutant huntingtin by targeting it for autophagic degradation, demonstrating an approach that may have potential for treating proteopathies., Author(s): Zhaoyang Li [sup.1] , Cen Wang [sup.1] , Ziying Wang [sup.1] , Chenggang Zhu [sup.2] , Jie Li [sup.3] , Tian Sha [sup.1] , Lixiang Ma [sup.4] , Chao [...]

Laser electrospray mass spectrometry (LEMS) is demonstrated for pharmaceutical samples at atmospheric pressure. A nonresonant, femtosecond duration laser pulse vaporizes native samples at atmospheric pressure into an electrospray plume for ionization with subsequent transfer into a time-of-flight mass spectrometer. The active ingredients in pharmaceutical tablets were detected in the presence of binders and fillers in intact formulations using LEMS. Mass spectra were also obtained for microgram amounts of the pharmaceutical compounds loratadine, oxycodone, and atenolol deposited on glass, wood, steel, and polyester fabric. The neutral capture efficiency by the electrospray plume for nonresonant laser vaporization of oxycodone and atenolol desorbed from steel is 2.4% [+ or -] 1.5% and 0.25% [+ or -] 0.18%, respectively. LEMS imaging of the spatial distribution of an oxycodone spot on a metal slide with resolution of 250 [micro]m is also presented. 10.1021/ac902880q

As hard-disk drives require higher recording density and reliability, the technology of the head--disk interface (HDI) is facing more challenging tasks regarding its tribological performance. Fluorinated lubricants are commonly used in the phase of near contact recording whose HDI is below 10 nm. However, conventionally obtainable compounds have some disadvantages derived from their chemical frameworks. QA-40 is a newly designed and synthesized fluorine-containing lubricant for near contact recording with desirable properties in chemical stability, friction force and adhesion. Index Terms--Hard disk, lubricant, head--disk interface, friction force.

In this study the magnetic properties and the structure of [Gd.sub.5][Ge.sub.1.8][Si.sub.1.8][Sn.sub.0.4] alloy were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and magnetometry. The concentration of the Sn-doping in this study is four times that used in previous studies examining the magnetocaloric properties of the [Gd.sub.5][Ge.sub.2][Si.sub.2] compound doped with different metal additives. In the earlier studies it was shown the addition of about one atom percent of either Fe, Cu, Co, Ga, Mn, or Al nearly eliminated the large hysteresis losses present in the undoped [Gd.sub.5][Ge.sub.2][Si.sub.2] compound between 270 K and 300 K. Also, these metal additives affected the characteristics [DELTA][S.sub.m] versus T peak, resulting in a significant increase in the refrigeration capacity of the material, if the hysteresis losses are taken into account. By contrast, the same amount of either Sn or Bi had much smaller effects on both the hysteresis losses and the characteristics of the [DELTA][S.sub.m] versus T peak. In this study, a larger amount of Sn doping had a limited effect on the hysteresis losses and characteristics of the [DELTA][S.sub.m] versus T peak of [Gd.sub.5][Ge.sub.2][Si.sub.2]. But, most importantly, it resulted in a different microstructure compared to the compound with smaller Sn addition. The implications of the larger Sn doping on both the magnetocaloric properties and structure of the [Gd.sub.5][Ge.sub.2][Si.sub.2] compound are discussed. Index Terms--Field-induced transition, hysteresis losses, magnetocaloric properties, Sn-doped GdGeSi compound.

The magneto-electric effect is very much enhanced in multiferroic composite materials due to the long range ferroic ordering and stress mediated magneto-electric coupling. This opens the possibility for applications of multiferroic composites to advanced magnetic, electric and motion sensors. When the magneto-electric effect is magnetically induced, the simultaneously application of a dc and ac magnetic fields is required. The magneto-electric coupling is strongly dependent on both ac/dc applied fields, the measurement geometry and the material properties. In this paper we demonstrate that the crystallographic texture of the magnetic phase within the multiferroic composite can be used to tune the magneto-electric coupling via the dc bias field. Ni[Fe.sub.2][O.sub.4]/PbZrTi[O.sub.3] bi-layer laminated multiferroic samples with various crystallographic textures of the Ni[Fe.sub.2][O.sub.4] have been investigated. We show almost a 300% reduction in the optimum dc bias magnetic field at which the maximum magneto-electric coupling has been observed. The observed reduction is directly related to the crystallographic texture of the Ni[Fe.sub.2][O.sub.4] component. Index Terms--Crystallographic texture, magneto-electric coupling, magneto-electric sensors, multiferroic composites.

We present a study of the magnetic properties and the [sup.57]Fe Mossbauer spectra of the [Hf.sub.1-x][R.sub.x][Fe.sub.6][Ge.sub.6], R = Gd and Dy, series. The macroscopic magnetic measurements are consistent with the magnetic independence of the R and Fe sublattices. However, the [sup.57]Fe Mossbauer study reveals a more complex magnetic behavior. Specifically, below [T.sub.t] [approximately equal to] 100 K a spin reorientation takes place in Hf[Fe.sub.6][Ge.sub.6]. The analysis of the corresponding Mossbauer spectra shows that below [T.sub.t] a fraction of the iron moments is canted from the c-axis. The substitution of Hf by Gd or Dy reduces the fraction of canted iron moments. The hyperfine magnetic fields are found to decrease upon the R = Gd or Dy substitution. This effect can be qualitatively explained as a result of the decrease in the hybridization between the d valence states of the R element with the 3d iron states. Index Terms--1-6-6 compounds, magnetic materials, Mossbauer spectroscopy.

Strontium ferrite (Sr[Fe.sub.12][O.sub.19]) thin films have been deposited on thermally oxidized silicon wafer with Au underlayer by using DC magnetron sputtering system. Crystallization of the strontium hexaferrite phase on Au underlayer is achieved for deposition temperature as low as 475[degrees]C. The intensity of (111) diffraction line for Au and that of (00l) diffraction line for strontium ferrite decreases with increasing substrate temperature of underlayer. The maximum of coercivity and remanent squareness ratio in perpendicular direction are 5.7 kOe and 0.86, respectively, at substrate temperature of underlayer of 200[degrees]C. Index Terms--Au, hexagonal ferrite, perpendicular recording, sputtering, strontium ferrite.

The CoCrPt thin films with longitudinal orientation of easy axis have been prepared by magnetron sputtering on CrW underlayer at room temperature. The crystallographic relationship between the CoCrPt thin film and the underlayer was studied, and the dependence of CoCrPt structure and magnetic properties on the Pt content was investigated. The addtion of Pt element in the CoCrPt magnetic layer increases the lattice constant and longitudinal coercivity of the CoCrPt thin films. The intrinsic stress of the CoCrPt(8.5% Pt content) thin film is analyzed by using the micromagnetic method. It is found that the in-plane magneto-elastic effect with a residual compressive stress on the order of 1.14 Gpa tends to enlarge the longitudinal coercivity, and the increased coercivity due to the magneto- elastic anisotropy is about 245 Oe, indicating that the magnetostriction effects play an important role on the coercivity mechanisms. Index Terms--CoCrPt film, CrW underlayer, magnetostriction, micromagnetic method.

Microdialysis sampling is a technique that has been used for in vivo and in vitro monitoring of compounds of pharmaceutical, biomedical, and environmental interest. The coupling of a commercially available microdialysis probe to a microchip-based capillary electrophoresis (CE) system is described. A continuously flowing dialysate stream from a microdialysis probe was introduced into the microchip, and discrete injections were achieved using a valveless gating approach. The effect of the applied voltage and microdialysis flow rate on device performance was investigated. It was found that the peak area varied linearly with the applied voltage. Higher voltages led to lower peak response but faster separations. Perfusion flow rates of 0.8 and 1.0 [micro]L/min were found to provide optimal performance. The on-line microdialysis/microchip CE system was used to monitor the hydrolysis of fluorescein mono-[beta]-D-galactopyranoside (FMG) by [beta]-D-galactosidase. A decrease of the FMG substrate with an increase in the fluorescein product was observed. The temporal resolution of the device, which is dependent on the CE separation time, was 30 s. To the best of our knowledge, this is the first reported coupling of a microdialysis sampling probe to a microchip capillary electrophoresis device.

2-Acetoxy-2-methoxy-5,5-dimethyl-[[DELTA].sup.3]-1,3,4-oxadiazoline undergoes two competitive 1,3-dipolar cycloreversions at 110[degrees]C. It loses [N.sub.2], presumably to afford a short-lived carbonyl ylide that fragments to acetone and acetoxy(methoxy)carbene. It also forms 2-diazopropane and the appropriate mixed anhydride. It is the only currently known source of acetoxy(methoxy)carbene. Key words: acetoxy(methoxy)carbene, 2-diazopropane, 1,3-dipolar cycloreversion.

The Ni-Fe-Ga-Co system has been proposed as a new magnetic shape memory alloy due to its wide temperature range for martensitic and magnetic transformations ([T.sub.m] and [T.sub.c], respectively) by changing composition. The alloy composition [Ni.sub.52][Fe.sub.17][Ga.sub.27][Co.sub.4] is more interesting for practical application due to its relatively high [T.sub.m] and [T.sub.c]. Here, martensitic transformations, crystal structures, and magnetic properties of [Ni.sub.52][Fe.sub.17][Ga.sub.27][Co.sub.4] alloys in form of bulk and powder are studied. Bulk samples were prepared by arc-melting followed by annealing at 1473 K for 4 h, while powder samples were filed from this bulk sample and annealed at 673 K for 0-15 h. The martensitic transformation present in the bulk sample totally disappears after powderisation. [T.sub.c] of the powder sample is about 100 K lower than that of the bulk one. The saturation magnetization of the bulk sample ([M.sub.sat] = 54 emu/g) is reduced significantly down to 35 emu/g by powderisation, but increased again with increasing annealing time. After annealing the powder for 15 h, the martensitic transformation recovers and [T.sub.c] is increased close to the level of the bulk sample. From room-temperature X-ray diffraction, it is found that the tetragonal non-modulated martensite in the bulk sample is completely transformed to a disordered fcc phase by powderisation, but gradually changes into a highly ordered [L2.sub.1] austenite phase during the subsequent annealing. Index Terms--Magnetic properties, magnetic shape memory (MSM) alloy, Ni-Fe-Ga-Co, structure.

We have investigated the exchange anisotropy in [L1.sub.2]-ordered [Mn.sub.3]Ir/[Co.sub.65][Fe.sub.35] bilayers with inserting ultra-thin [Co.sub.x][Fe.sub.100-x](x > 65) layer at the interface between [L1.sub.2]-[Mn.sub.3] Ir and [Co.sub.65][Fe.sub.35] layer. The unidirectional anisotropy constant, [J.sub.K], was enhanced from 0.93 erg/[cm.sup.2] to 1.2erg/[cm.sup.2] at the range from 85 to 98 at. % of Co composition in [Co.sub.x][Fe.sub.100-x] insertion layer. The crystal structure of the ultra-thin [Co.sub.90] [Fe.sub.10] insertion layer was transformed to bcc structure following the bcc structured [Co.sub.65] [Fe.sub.35] layer during thermal annealing. These results suggest that the enhancement of exchange anisotropy with ultra-thin [Co.sub.x][Fe.sub.100-x] (x > 80) insertion layer is attributed to the Co-rich bcc phase formation in the insertion layer. Index Terms--[Co.sub.x][Fe.sub.100-x](x > 80) insertion layer, exchange anisotropy, [L1.sub.2]-ordered [Mn.sub.3]Ir, unidirectional anisotropy constant, [J.sub.K].

Defects such as oxygen vacancies play a crucial role in the surface properties of transition metal oxides. By means of time-resolved, high-resolution scanning tunneling microscopy, we unraveled an adsorbate-mediated diffusion mechanism of oxygen vacancies on rutile Ti[O.sub.2](110). Adsorbed oxygen molecules mediate vacancy diffusion through the loss of an oxygen atom to a vacancy and the sequential capture of an oxygen atom from a neighboring bridging oxygen row, leading to an anisotropic oxygen vacancy diffusion pathway perpendicular to the bridging oxygen rows., Transition metal oxide surfaces play an important role in a wide range of applications such as heterogeneous catalysis, photo-electrolysis, biocompatibility, and sanitary disinfection (1-4). Defects such as oxygen vacancies often [...]

Byline: Hermann A. Jehn Besides the chemical composition, the structure basically determines all properties of thin films and coatings. In this sense, structure means the morphology, crystallite size, texture, lattice parameter and defects. In order to fabricate tailored coating properties, the effect of the different deposition parameters has to be known, in particular deposition rate, type and degree of ionization of the impinging species, substrate temperature and bias as well as geometrical arrangement and dimensions. After a short description of the fundamentals of nucleation and film growth as well as the present types of structure zone models, examples are given for the influence of deposition parameters on properties of reactively and non-reactively vapor-deposited coatings.

Byline: Liqing Hao, Zhenya Wang, Mingqiang Huang, Li Fang, Weijun Zhang A home-made Single Aerosol Laser Mass Spectrometer (SALMS) was utilised to provide on-line measurements of the sizes and molecular compositions of Secondary Organic Aerosols (SOAs) from irradiating toluene in the smog chamber. Results demonstrate that variations in reaction conditions make a little difference in the size and chemical composition distributions of SOAs. According to the reaction mechanisms, some aromatic ring-retaining and ring-opening products have been tentatively identified. Compounds from the H-abstraction pathways contribute more to the aromatic ring-reserved products. Those ring opening products could be produced from OH-addition pathways via two important intermediate species 6-oxo-2,4-heptadienal and 5-methyl-6-oxo-2,4-hexadienal isomers.

Byline: Mirela Britchi, M. Olteanu, N. Ene Some vitroceramics belonging to the oxidic system SiO2-CaO-P2O5-B2O3-Na2O-K2O-Li2O-MgO-TiO2 were prepared and then characterised by optical microscopy and microhardness trials. The frits from the above mixture were turned into composite materials by reinforcing them with 0.1-0.8% in weight Ti powder. Both simple and composite frits were used for coating the titanium plates by enamelling. The vitroceramic layer-titanium couples were characterised by means of optical microscopy and microhardness trials. From hardness tests made at vitroceramic layer-metallic substrate interface adherence of the layer to the substrate was determined. By reinforcing the vitroceramic frits with titanium powder we tried to increase the fracture toughness and decrease the brittleness of the coating layers. These quantities were computed from Vickers microhardness values, indentation forces, measurements of the microhardness imprint diagonals and cracks that propagate from the imprint corners.

The six-parameter quantitative structure-property relationship (QSPR) model is used to describe the gas-phase lithium cation basicity (LCB) for a diverse set of 205 compounds. The statistical validation of the model revealed that the proposed model has a normal statistical stability and validity.

The experiments, which probe the influence of salt (sodium chloride) on the rate of solute exchange in sodiumdedecyl sulfate (SDS) micelles, are presented. The range of salt concentrations near the transition from spherical micelles to rodlike assemblies is discussed.

The alternative carbazole derivatives for small-molecule organic light-emitting diodes (OLEDs), based on derivatization at the phenyl rings of the carbozoles unit, are presented. The influence of substitution of carbazoles at the phenyl rings, and the nitrogen on spectroscopical and electrochemical properties relevant for OLEDs are discussed.

A series of Fe(II) amido complexes is synthesized using beta-diketiminates to enforce low coordinate numbers. It is found that the basic nitrogen atom is protonated by terminal alkynes and alcohols to give three-coordinate iron acetylide and alkoxide complexes.

To study the reaction mechanism of [Fe(Tp(super Ph2))BF] (Tp(super Ph2) = hydrotris(3,5-diphenylpyrazol-1-yl)borate; BF = benzoylformate) with oxygen, Density functional calculations using the B3LYP functional are used. The results support a mechanism in which oxidative decarboxylation of the keto acid is the rate-limiting step.

TDOS and M-M COHP curves fort he zeta(sub 2)-GaM (M = Cr, Mn, Fe) compounds zeta2-GaFe and zeta-GaCr is refined using x-ray powder diffraction as well as neutron powder diffraction for zeta2-GaFe. Recent investigations showed that these two compounds are isostructural to zeta-GaMn.

Dentrimers with a Cu(I) bis(2,9-diphenethyl-1,10-phenanthroline) core surrounded by frechet type dendritic branches have been prepared and the kinetics of their cyanide-assisted demetalation studied.

Two unique cynano-bridged 2D coordination polymers have been synthesized and characterized structurally and magnetically. The structures are composed of two isomeric polyaza Cu(II) units and one novel macromolecular metallic compound.

The intermetallic compounds R7+(sub x)Os(sub 12)Al(sub 61+y)(R=Y, Nd, Sm, Gd-Tb) crystallize with a hexagonal structure, which is recognized as belonging to a relatively new structural family with layered topology. Different structures showing atomic layers are presented.

The bis-phenyltin-substituted, lone pair-containing tungstoarsenate[(C6H5Sn)2As(sub 2)W(sub 19)O(sub 67)(H2O)](super 8-) consists of two B-alpha-(As (III)W9O(sub 33)) keggin moieties linked via a Wo(H2O) fragment and two SnC6H5 groups leading to a sandwich-type structure with nominal C2u symmetry. The solution and solid properties of a bis(monoorganotin) derivative of the dilacunary tungstoarsenate(III) [As2W(sub 19)O(sub 67)(H2O)(super 14-) is reported.

To rationalize the geometry of the d(super 0) fluorides, hydrides, methanides, and oxides of the period 4 metals from Ca to Cr, the electron localization function is used. An extensive study of d(super 0) molecules, using the electron localization function is presented.

To study the demetalation process observed upon reduction of Fe(III) centers in a large family of multi-iron Wells-Dawson polyoxometalates, the cyclic voltammetry and controlled potential coulometry is used. A report showing a series of multi-iron sandwich-type complexes that are effective catalysts is presented.

The remarkable chemical compressibility of the type I clathrate framework was found for a novel Sn(sub 24)P(sub 19).3Br(sub x)solid solution. The structural study reveals that the thermal contraction of the structure is similar to that of conventional semi conducting clathrates.

Interesting features of the nitrogenase cofactor, which includes short Fe-Fe distances in an electron deficient MoFe7S9 core, are presented. Density functional theory (DFT) calculations were carried out on model clusters to explore the Fe-Fe interactions in the cofactor.

The reaction of (CH3)3SnCl with HOTeF5 or CIOTeF5 yields (CH3)2SnCL(OTeF5), which was characterized by multinuclear NMR and vibrational spectroscopy as well as single crystal x-ray diffraction, is presented. The results of the NMR spectroscopic study are discussed.

A novel 2D heterometallic network {[Rh2(O2CCF3)(sub 4)].mu2-OCMe2.[Cu4(O2CCF3)(sub 4)]} infinity is prepared by gas-phase deposition of the volatile mono(acetone) adduct [Rh2(O2-CCF3)(sub 4).meu1-OCMe2](sub 2) and tetracopper(I) trifluoroacetate, [Cu4(O2CCF3)(sub 4) . Details on the preparation, spectroscopic characterization, and X-ray diffraction study of the title compound are reported.

Thermolytic decomposition of bis(N-alkyldithiocarbamato)cadmium(II) complexes, [Cd(S2CNHR)2], results in desulfurization of RHNCS2(super -1) to give the corresponding isothiocyanate and cadmium sulfide. Evidence suggests that proton transfer is required prior to the desulfurization step.

The electronic spectra of the tetravalent [Mo(CN)8](super 4-) and [W(CN)8](super 4- )complexes is theoretically investigated by ab initio techniques. A detailed analysis of the ligand-field part of the experimental spectra points to the existence of a dynamical equilibrium between the two isomeric forms of the title octacyanocomlexes, namely the dodecahedron (D(sub 2d)) and square antiprism (D(sub 4d)).

PdCl2 and PtCl2 complexes of the redox active diphosphine P2 have been synthesized, and the palladium one is structurally characterized. It is found that the single crystal x-ray analysis on the resulting compound showed the formation of a dimeric complex salt, formulated as [(dppen)PdCl](sub 2)(OTf)(sub 2).

With the synthesis of two new manganese chloride salts, the synthetic utility of the solvothermal dehydration reaction using superheated acetonitrile is demonstrated. It is shown that the one-dimensional heissenberg antiferromagnet, [NH4]MnCl2(OAc), is prepared by the novel synthetic strategy of solvothermal dehydration.

Using two types of exchange-correlation functionals and various basis sets an effort is made to investigate the electronic structures of Ni3(dpa)4Cl2 within the framework of the density functional theory (DFT). It is found that one-electron oxidation of the neutral complex yields a reorganization of the electronic distribution in the metallic framework.

The mixed-ligand polymers {[M(diphos)(CN-t-Bu)2]BF4}n (M = Cu, Ag; diphos = dppm, dppb, dpppen, dpph) and {[M(diphos)(dmb)]BF4}n(dmb = 1,8-diisocyano-p-menthane) are synthesized and characterized. TGA, DSC, XRD, and solid-state luminescence spectra and emission lifetimes are reported.

The kinetic characteristics of the intramolecular proton transfer from [lutH](super +1) to sulfur have been investigated, including the effect of the 4-R-substituents on the rate of proton transfer, the temperature dependence, and the isotope effects.

A study conducted using stopped flow spectrophotometry on the kinetics and temperature dependence of the equilibrium reactions between [Ni(SC6H4R-4)2(dppe)] (R= MeO, Me, H, Cl, or NO2; dppe = Ph2PCH2CH2PPh2) and mixtures of [lutH]+ and lut (lut = 2,6-dimethylpyridine) in MeCN to form [Ni(SHC6H4R-4)(dppe)+, is presented.

It been shown that compounds of the forms [2,2-L2-closo-2,1,7-NiC2B9H11], which display interesting dynamic properties in solution is obtained by protonation of the species [NEt4]-[2-(eta3-C3H4R)-closo-2,1,7-NiC2B9H11] (R = H, Ph) in the presence of donors (L = CO, CNBut, L2 = diene).

In an effort to model electronic and structural features of protein metal centers with Fe(mu-O(H))(sub 2)Fe cores, differrous, mixed-valence, and diferric clusters are synthesized. A report on the x-ray structures and spectroscopic data is also presented.

Structural and thermodynamic parameters for the inorganic hetercyclic compounds [XMYH](sub n) (M = Al, Ga, In; Y = N, P, As; X = H, F, Cl, Br, I; n = 1-6) are predicted at the B3LYp/LANL2DZ(d,p) level of theory. Trends with respect to cluster size, and the influence of the metal, pnictogen atoms, and terminal group x on the structures and stability of clusters is discussed.