bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrocatalytic Reduction of Oxygen by Viologen-Linked Polypyrrole Coated on Glassy Carbon Electrode
Authors: Kijima Masashi , Sakawaki Akira , Sato Takeo 
Published: July 2006

Abstract
Viologen linked-N-substituted pyrroles were prepared and polymerized by electrochemical oxidation on glassy carbon, giving viologen-modified electrodes. The electrons were transferred from the modified electrode to O2 through the viologen moiety. The modified electrode worked as reactive electrodes for the selective electrocatalytic reduction of O2 to H2O2.
Synthesis of N-(9-Oxo-7-phenyl-9H-pyrano[2,3-g]benzothiazol-2-yl)benzamides from 6-Aminoflavone
Authors: Rao Mantripragada Narayana , Sambaiah Thota , Krupadanam Gazula Levi David , Srimannarayana Gotety 
Published: July 2006

Abstract
6-Aminoflavone (1) was treated with aroyl isothiocyanate in acetone at reflux temperature yields N-aroyl-N′-(2-phenyl-4-oxo-4H-[1]benzopyran-6-yl)thioureas (2). The products obtained on reaction of 2 with PCl5 in POCl3 medium leads to N-(9-oxo-7-phenyl-9H-pyrano[2,3-g]benzothiazol-2-yl)benzamides (4). The structures of the compounds synthesized were established by analytical and spectral data.
Synthesis of Phenylacetic Acid via Carbonylation of Benzyl Chloride in the Presence of a Water-Soluble Complex, [PdCl2{PPh2(m-C6H4SO3Na)}2], and Surfactants under Two-Phase Conditions
Authors: Okano Tamon , Hayashi Tetsuji , Kiji Jitsuo 
Published: July 2006

Abstract
The addition of surfactants such as n-C7H15SO3Na or n-C7H15COONa is effective in acceleration of the carboxylation of benzyl chloride using a water-soluble catalyst, [PdCl2{PPh2(m-C6H4SO3Na)}2], in an aqueous NaOH–heptane solution. Phenylacetic acid is easily isolated from the aqueous layer in high yields. However, the addition of n-C7H15SO3Na has no effect on the carboxylation using hydrophobic catalysts, [PdCl2(PPh3)2] and [Pd(PPh3)4], under the two phase conditions.
Photosensitized Electron-Transfer Reaction of 3-Aryl-2-methyloxaziridine: Direct Deoxygenation from the Isomeric Arylnitrone
Authors: Iwano Yasunori , Kawamura Yasuhiko , Miyoshi Hiroki , Yoshinari Toshifumi , Horie Tokunaru 
Published: July 2006

Abstract
Photosensitized electron-transfer reactions of 3-aryl-2-methyloxaziridines gave mainly the corresponding benzaldehydes, whereas the isomeric nitrones gave imines as well as aldehydes. Deoxygenation of the nitrone occurred via the nitrone cation radical under the reaction conditions. An aryl substituent effect on the reaction and isomerizations of both cation radicals are also discussed.
Crystal Structures of TMEO-TTP and (TMEO-TTP)[AuBr2]·THF
Authors: Misaki Yohji , Nishikawa Hiroyuki , Yamabe Tokio , Mori Takehiko , Inokuchi Hiroo 
Published: July 2006

Abstract
The molecular and crystal structures of the title compounds, where TMEO-TTP is 2-[4,5-bis(methylthio)1,3-dithiol-2-ylidene]-5-[4,5-ethylenedioxy-1,3-dithiol-2-ylidene]-1,3,4,6-tetrathiapentalene, have been investigated by X-ray crystal structure analysis. The BDT-TTP skeleton of neutral TMEO-TTP adopts a slightly flat chair conformation. The crystal has a columnar structure, in which the molecules dimerize in a head-to-tail manner. Several S···S contacts shorter than the sum of the van der Waals radii (3.70 Å) are observed along the transverse direction. (TMEO-TTP)[AuBr2]·THF also has a columnar structure in which the donor molecules dimerize. However, “side-by-side” interaction between the donors is prohibited because the AuBr2 anions and the THF molecules are located at the sides of the donor molecules.
Interaction of Sodium 4′-(Butylamino)azobenzene-4-sulfonate with Octyl Methyl Sulfoxide in Adsorbed Film and Micelle
Authors: Tanaka Fudeko , Harada Yuzo , Ikeda Norihiro , Aratono Makoto , Motomura Kinsi 
Published: July 2006

Abstract
The surface tension of the aqueous solution of sodium 4′-(butylamino)azobenzene-4-sulfonate (SBAS) and octyl methyl sulfoxide (OMS) mixture was measured as a function of the total molality at various compositions and at 298.15 K under atmospheric pressure. The experimental results were analyzed by applying the thermodynamic relations. The phase diagrams of adsorption and micelle formation were found to suggest that SBAS and OMS molecules interact attractively with each other to form a negative azeotropic mixture in the adsorbed film at a low surface tension and in the micelle. These findings were qualitatively similar to those of the system of SBAS and 2-(octylsulfinyl)ethanol (OSE) and confirmed our conclusion that the strong interaction of dye and nonionic surfactant molecules at the interface may be the one of reasons why a nonionic surfactant acts as the leveling agent in dyeing process.
Mixing Schemes and Liquid–Solid Phase Diagram in the Water-Rich Region of Aqueous 2-Butoxyethanol
Authors: Koga Yoshikata , Tanaka Toshiaki , Atake Tooru , Westh Peter , Hvidt Aase 
Published: July 2006

Abstract
Liquid–solid phase diagram was determined in the water-rich region of aqueous 2-butoxyethanol. A solid addition compound was suggested with the composition = 0.0260, which melts incongruently at 269.5 K. The mixing scheme boundary separating two regions in the single liquid phase domain (Chem. Phys. Lett., 217, 245 (1994)) was found to cross the incongruent melting point of the above solid addition compound.
Determination of the Critical Micelle Concentrations and Microviscosity with a Fluorescence Probe, Auramine
Authors: Miyagishi Shigeyoshi , Kurimoto Hirotaka , Ishihara Yuuhichi , Asakawa Tsuyoshi 
Published: July 2006

Abstract
A new method based on the fluorescence intensity of bis[4-(dimethylamino)phenyl]methanimine (auramine) was proposed in order to determine the critical micelle concentration (cmc). The cmc values of the following surfactants were determined by the present method, and were compared with those by a surface-tension method. The nonionic surfactants used were homogeneous polyethylene glycol monododecyl ether (C12E5, C12E6, C12E7, and C12E8) and N-acyl-N-methylglucamine (MEGA-7, -8, -9, -10, and -12). The cationic surfactants were dodecyltrimethylammonium chloride and bromide (DTAC, DTAB), tetradecyltrimethylammonium bromide (TTAB), hexadecyltrimethylammonium chloride and bromide (CTAC, CTAB). The potassium salt of N-acylalanines, the sodium salt of N-acylvalines, and sodium dodecyl sulfate were used as anionic surfactants. The cmcs measured by both methods were in good agreement with each other in all systems of surfactants used. The effects of added salt, temperature, and size of the acyl group on the microviscosity were also estimated.
Photochemical Reaction of Trichloroacetic Acid with Diphenylamine and Its Analytical Application
Authors: Pal Anjali 
Published: July 2006

Abstract
A method for the determination of trichloroacetic acid (TCA) in a simple spectrophotometric way has been described. It is based on the photochemical reaction of TCA with diphenylamine (DPA) which forms a green colored product (λmax: 652 nm). The relative standard deviation for all measurements is &lt;7%. A linear calibration graph is obtained in the concentration range of 610 to 2875 ppm with a correlation coefficient 0.990. The method is simple, rapid and does not require any costly and hazardous chemical. The effect of solvent, reagent concentration, time of irradiation etc. have been discussed. Extraction of TCA from contaminated water or urine with upto 10 fold increase in concentration followed by photochemical reaction and absorption measurement showed good correlation with the theoretical value. The interference by chloroacetic acid (MCA), dichloroacetic acid (DCA), chloroform (CHCl3), carbon tetrachloride (CCl4), trichloroethylene (TCE), and perchloroethylene (PCE) have also been studied.
Magnetochemical and Molecular Orbital Analyses on Lithium Electrochemically Doped Non-Graphitizable Carbon Electrode of Lithium Ion Rechargeable Batteries
Authors: Tanaka Koichi , Ata Masafumi , Kimura Hitoshi , Imoto Hiroshi 
Published: July 2006

Abstract
The electronic characteristics of electrochemically doped lithium in non-graphitizable carbon, which was obtained by heat-treating polyfurfuryl alcohol (PFA-C) and was used as the negative electrode of lithium ion rechargeable batteries, were examined with the aid of 7Li solid-state nuclear magnetic resonance (NMR) and electron spin resonance (ESR). In order to clarify how lithium is incorporated in the carbon electrode, discrete variational-Xα (DV-Xα) molecular-orbital calculations were also performed on a model system. These experimental and theoretical results suggest that the lithium doped in the carbon exists in a non-metallic state with low electron density as compared to the ionic crystal, and that the unpaired electrons in the lithium doped carbon are delocalized at the peripheral carbon domains of the system. This was theoretically supported by the fact that the singly occupied molecular orbital (SOMO) of the lithium doped carbon is lower by 5.388 eV than the orbital localized predominantly on lithium 2s, and that the system is stabilized by electron donation from lithium to the carbon.
Structure and State-Energy Relationship of Photo-Excited Cu(I) Complex
Authors: Shinozaki Kazuteru , Kaizu Youkoh 
Published: July 2006

Abstract
Excited [CuI(dmphen)2]+ (dmphen = 2,9-dimethyl-1,10-phenanthroline) was studied in terms of its molecular structure. The MLCT (metal-to-ligand charge-transfer) transition energy and phosphorescence lifetime of the copper(I) complex in the solid state were reduced with diminishing the dihedral angle between two dmphen ligands. The results of a DV-Xα molecular orbital calculation were in good agreement with the spectroscopic results. In solution, the non-luminous character of [CuI(phen)2]+ (phen = 1,10-phenanthroline), which had no steric-hindered methyl groups retarding the flattening motion, was explained from lowering the lowest excited MLCT state due to a drastic distortion by the photoexcitation.
Photoracemization of Ruthenium(II) Complexes with 2,2′-Bipyridine and Di-2-pyridylamine
Authors: Nagao Noriharu , Mukaida Masao , Miki Eiichi , Mizumachi Kunihiko , Ishimori Tatujiro 
Published: July 2006

Abstract
The emission lifetime (τobs) and quantum yield of photoracemization (φrac) for a series of complexes, [Ru(bpy)n(Hdpa)3−n]2+ (n = 0—3), were studied in aqueous solution at temperatures of between 20 and 60 °C. The values of τobs of [Ru(bpy)2(Hdpa)]2+ were found to vary around 80—200 ns, depending upon temperature, while [Ru(bpy)(Hdpa)2]2+ and [Ru(Hdpa)3]2+ did not emit at the temperature studied. The photoracemization reactions of [Ru(bpy)3]2+, [Ru(bpy)2(Hdpa)]2+, [Ru(bpy)(Hdpa)2]2+, and [Ru(Hdpa)3]2+ were thermally activated with φrac of (0.1—1.6) × 10−3, (0.5—6) × 10−3, (0.04—0.22) × 10−3, and (0.1—0.25) × 10−3, respectively, depending upon the conditions. The photochemical behavior of [Ru(bpy)2(Hdpa)]2+ was explained by a set of excited states, which was assumed to include the 3d–π*bpy, 3d–d*, and 3n–π*bpy states. The reactive state, the 3d–d* state, was thermally yielded from the 3d–π*bpy state. The displacement of a bpy ligand by an Hdpa ligand made the quantum yield of the formation of the 3d–d* state from the 3d–π*bpy state (φd–d) smaller, and the intrinsic quantum yield of photoracemization (φrac(d–d)) larger. The fact that φrac for [Ru(bpy)(Hdpa)2]2+ and [Ru(Hdpa)3]2+ was smaller than that for [Ru(bpy)3]2+ and [Ru(bpy)2(Hdpa)]2+ could be interpreted by assuming that the displacement of the bpy ligand by the Hdpa ligand diminished the quantum yield of the formation of the 3d–d* state from the 3d–π*bpy or 3d–π*Hdpa states considerably, due to the bypath from the 3d–π*bpy or 3d–π*Hdpa states through the 3nHdpa–π*bpy or 3nHdpa–π*Hdpa states to the ground state.
Intramolecular Ligation of Carbonyl Oxygen to Central Zinc in Synthetic Oligopeptide-Linked Zinc-Porphyrins
Authors: Tamiaki Hitoshi , Kiyomori Ayumu , Maruyama Kazuhiro 
Published: July 2006

Abstract
Oligopeptide-linked zinc-porphyrins were prepared (oligopeptide = –Phem–Alan–OMe and porphyrin = 5,15-diaryl-2,3,7,8,12,13,17,18-octaethylporphyrin). 1H NMR, IR, visible, and CD spectra of the synthetic molecule in a chlorinated methane (CDCl3 or CH2Cl2) showed that the carbonyl oxygen of the N-terminal amino acid of the linked peptide should ligate the central zinc metal in the molecule as the axial ligand to form a pentacoordinated zinc-porphyrin. The coordination of the zinc with the peptide framework changed the optical and electrical properties, indicating that such ligation might control the reactivity in biological metallotetrapyrrole–protein systems as well as the coordination to the peptide residue.
Convenient Synthesis of 1α,25-Dihydroxyvitamin D3 from Vitamin D2
Authors: Takahashi Minokazu , Sakakibara Yasumasa 
Published: July 2006

Abstract
(1S,6R)-1-Acetoxy-6-(1,3-benzodithiol-2-yloxy)-3,5-cyclovitamin D2 (7) was synthesized from vitamin D2 by five steps. The new compound 7 was ozonized regioselectively and subsequently reduced, leading to (7E)-(1S,3S,5R,6R)-1-acetoxy-6-(1,3-benzodithiol-2-yloxy)-3,5-cyclo-9,10-seco-23,24-dinor-7,10(19)-choladien-22-ol (11). The alcohol 11 obtained as a key intermediate was tosylated, iodinated, and coupled with 2-methyl-4-phenylsulfonyl-2-(tetrahydropyranyloxy)butane to give (1S,6R)-1-hydroxy-6-(1,3-benzodithiol-2-yloxy)-23-phenylsulfonyl-25-tetrahydropyranyloxy-3,5-cyclovitamin D3 (16). By desulfonylation and hydrolysis of the compound 16 1α,25-dihydoxyvitamin D3 was obtained selectively.
Synthesis and Properties of Conjugated Porphyrins with a Diacetylene Spacer
Authors: Imahori Hiroshi , Higuchi Hiroyuki , Matsuda Yoshihiko , Itagaki Ayano , Sakai Yoshie , Ojima Jûro , Sakata Yoshiteru 
Published: July 2006

Abstract
A series of (porphyrin)–(C≡C)2–C6H4–R1 (R1 = NO2, H, Me, and OMe) were synthesized by the oxidative coupling of ethynyl porphyrins and phenylacetylenes in the presence of copper(II) acetate in pyridine. Electronic and electrochemical spectra of the compounds with R1 = H, Me, and OMe are quite similar, while pronounced change was observed for the compound with R1 = NO2, especially for the meso-substituted one, indicating that intramolecular charge transfer is responsible for the difference.
Stereoselective Addition of Organoaluminium or Organomanganese Reagents to α-Formyl Amides or α-Methyl-Substituted β-Keto Amides
Authors: Taniguchi Masahiko , Fujii Hideaki , Oshima Koichiro , Utimoto Kiitiro 
Published: July 2006

Abstract
Treatment of α-formyl amides with RAlCl2 or PhAlCl2 provided threo-α-alkyl-substituted β-hydroxy amides under high stereocontrol. The method was successfully applied to the selective addition of alkyl group to α-methyl-substituted β-keto amides or esters. Treatment of α-methyl-β-keto amides or α-methyl-β-keto esters with trialkylaluminium or alkylmanganese halide afforded the corresponding erythro (or threo) α-methyl-substituted β-hydroxy amides or α-methyl-substituted β-hydroxy esters with high stereoselectivity.
Titanium(III)-Induced Transformation of Hydroxylamines to Imines or Secondary Amines
Authors: Kodera, Yoichi , Watanabe Shoji , Imada Yasushi , Murahashi Shun-Ichi 
Published: July 2006

Abstract
N,N-Disubstituted and cyclic hydroxylamines can be converted into the corresponding imines efficiently upon treatment with anhydrous titanium trichloride in THF at room temperature. Similar treatment of N-allylhydroxylamines with anhydrous titanium trichloride gives 1-azadienes, which are versatile synthetic intermediates for aza-Diels–Alder reactions. On the other hand, the same hydroxylamines can be converted into the corresponding secondary amines upon treatment with aqueous titanium trichloride in methanol. It is noteworthy that optically active hydroxylamines, which have chirality at the α-position to nitrogen, can be converted into optically active secondary amines without loss of chirality. Dihydro-2(1H)-quinolinones can be prepared upon treatment of 1-hydroxy-3,4-dihydro-2(1H)-quinolinones with aqueous titanium trichloride. The substrates of N,N-disubstituted and cyclic hydroxylamines can be prepared readily upon treatment of nitrones with nucleophiles. Since nitrones can be prepared by metal-catalyzed oxidations of secondary amines with hydrogen peroxide, the present titanium(III)-promoted reaction of hydroxylamines will provide a convenient method for the synthesis of either α-substituted imines or amines from secondary amines.
Ruthenium–Niobia Interaction in Nb2O5-Supported and Nb2O5-Modified Ru Catalysts
Authors: Kunimori Kimio , Shindo Hisakazu , Nishio Daisuke , Sugiyama Takeshi , Uchijima Toshio 
Published: July 2006

Abstract
The effect of H2 reduction treatments on H2 chemisorption, ethane hydrogenolysis, and CO hydrogenation over Nb2O5-supported and Nb2O5-modified Ru catalysts has been studied to elucidate the nature of the metal-oxide interaction, and the results are compared with those of a SiO2-supported Ru catalyst. The Ru/Nb2O5 and Nb2O5–Ru/SiO2 catalysts after high-temperature reduction at 500 °C showed a typical SMSI behavior, while a specific Ru–niobia interaction, which resulted in a higher ethane hydrogenolysis activity, was induced even after low-temperature reduction at 200 °C.
Physical Properties of 3-s-Butylsydnone
Authors: Sasaki Yukio , Komiya Ichiro , Handa Minoru 
Published: July 2006

Abstract
The physical properties of 3-s-butylsydnone at various temperatures were investigated by dielectric constant, refractive index, density, and viscosity measurements. These physical constants were compared with those of other 3-alkylsydnones. Although the differences in the dielectric constant, refractive index and density between 3-butylsydnone and 3-s-butylsydnone were relatively small, the viscosity of 3-s-butylsydnone became particularly larger than that of 3-butylsydnone at lower temperatures.
Synthesis and Properties of Dinuclear Copper(II) Complexes Containing Dinucleating Ligands with Imidazole Nitrogen and Two Exogenous Bridging Ligands
Authors: Nakao Yasuo , Oonishi Makoto , Uzu Tomoko , Kashihara Hiroko , Suzuki Shinnichiro , Sakai Masahiro , Fukuda Yutaka 
Published: July 2006

Abstract
Dinuclear copper(II) complexes, [Cu2(nR)X2] (ClO4)2 (X = N3−, NCS−, and OAc−) have been synthesized and characterized, where nR = N,N,N′,N′-tetrakis[(1-methyl-2-benzimidazolyl)methyl]-1,3-diaminopropane (3Me), N,N,N′,N′-tetrakis[(1-ethyl-2-benzimidazolyl)methyl]-1,3-diaminopropane (3Et), N,N,N′,N′-tetrakis[(1-methyl-2-benzimidazolyl)methyl]-1,4-diaminobutane (4Me), and N,N,N′,N′-tetrakis[(1-ethyl-2-benzimidazolyl)methyl]-1,4-diaminobutane (4Et). Although a weak antiferromagnetic interactions were found for [Cu2(3Me)(NCS)2](ClO4)2·3H2O (coupling constant J = −2.1 cm−1, H = −2JS1·S2) and [Cu2(3Me)(OAc)2](ClO4)2·H2O (J = −2.0 cm−1), no exchange interaction has been observed to 4.2 K for [Cu2(3Me)(N3)2](ClO4)2·H2O. The Electrochemistry of these complexes in N,N-dimethylformamide showed two electron reductions at +210 — −30 mV vs. Ag–AgCl (Cu2+–Cu2+ → Cu+–Cu+).
The Wittig Rearrangement of Chiral S-Methyl Phosphinothioates Promoted by Direct Deprotonation with Lithium Dialkylamides
Authors: Kawashima Takayuki , Kojima Satoshi , Inamoto Naoki 
Published: July 2006

Abstract
Sequential treatment of S-methyl (t-butyl)phenyl- or (1-naphthyl)phenylphosphinothioates with lithium dialkylamides at −78 °C and then with alkyl halides at 0 °C—r.t. gave the corresponding (alkylthiomethyl)phosphine oxides, the Wittig rearrangement products, in moderate to good yields along with small amount of their overreacted α-alkylated products. The corresponding alkylphosphine oxide was obtained only in the reaction of naphthyl derivative. Optically active Wittig rearrangement products were given in 82 and 78% optical yields, respectively.
Catalytic and Thermal Behavior of Cerium Oxide Supported onSiO2 and Al2O3 for Methane Combustion
Authors: Haneda Masaaki , Mizushima Takanori , Kakuta Noriyoshi , Ueno Akifumi 
Published: July 2006

Abstract
CeO2/SiO2 and CeO2/Al2O3 catalysts oxidized at 1173 K in O2 stream were employed to investigate the catalytic activity for methane combustion and the behavior of CeO2 on supports by the oxidation at 1173 K. CeO2/SiO2 catalyst gave a poor catalytic activity by comparison with that of CeO2/Al2O3 catalyst. The crystallite size of CeO2 of the silica catalyst was found to be 1.5 times larger. In addition, Auger Electron Spectroscopy (AES) analysis after the oxidation at 1173 K proved that cerium species existed on and within the silica support. We conclude that the low surface density of CeO2 might contribute to the poor activity of CeO2/SiO2 catalyst for methane combustion.
The management of failed ankle replacement
Authors: Kotnis R. , Pasapula C. , Anwar F. , Cooke P. H. , Sharp R. J. 
Published: July 2006

Advances in the design of the components for total ankle replacement have led to a resurgence of interest in this procedure.Between January 1999 and December 2004, 16 patients with a failed total ankle replacement were referred to our unit. In the presence of infection, a two-stage salvage procedure was planned. The first involved the removal of the components and the insertion of a cement spacer. Definitive treatment options included hindfoot fusion with a circular frame or amputation. When there was no infection, a one-stage salvage procedure was planned. Options included hindfoot fusion with an intramedullary nail or revision total ankle replacement. When there was suspicion of infection, a percutaneous biopsy was performed. The patients were followed up for a minimum of 12 months.Of the 16 patients, 14 had aseptic loosening, five of whom underwent a revision total ankle replacement and nine a hindfoot fusion. Of the two with infection, one underwent fusion and the other a below-knee amputation. There were no cases of wound breakdown, nonunion or malunion.Management of the failed total ankle replacement should be performed by experienced surgeons and ideally in units where multidisciplinary support is available. Currently, a hindfoot fusion appears to be preferable to a revision total ankle replacement.
Congenital dislocation of the hip
Authors: Vallamshetla V. R. P. , Mughal E. , O’Hara J. N. 
Published: July 2006

Difficulties posed in managing developmental dysplasia of the hip diagnosed late include a high-placed femoral head, contracted soft tissues and a dysplastic acetabulum. A combination of open reduction with femoral shortening of untreated congenital dislocations is a well-established practice. Femoral shortening prevents excessive pressure on the located femoral head which can cause avascular necrosis. Instability due to a coexisting dysplastic shallow acetabulum is common, and so a pelvic osteotomy is performed to achieve a stable and concentric hip reduction. We retrospectively reviewed 15 patients (18 hips) presenting with developmental dysplasia of the hip aged four years and above who were treated by a one-stage combined procedure performed by the senior author. The mean age at operation was five years and nine months (4 years to 11 years). The mean follow-up was six years ten months (2 years and 8 months to 8 years and 8 months). All patients were followed up clinically and radiologically in accordance with McKay’s criteria and the modified Severin classification. According to the McKay criteria, 12 hips were rated excellent and six were good. All but one had a full range of movement. Eight had a limb-length discrepancy of about 1 cm. All were Trendelenburg negative. The modified Severin classification demonstrated four hips of grade IA, six of grade IB, and eight of grade II. One patient had avascular necrosis and one an early subluxation requiring revision. One-stage correction of congenital dislocation of the hip in an older child is a safe and effective treatment with good results in the short to medium term.