bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship between the reciprocal of analyte‐‐line intensity and the reciprocal of weight fraction and its utilization in x‐ray fluorescence analysis
Authors: Asada Eiichi , Matsuda Shoji , Suzuki Yoshiko , Nakamura Mitsuo , Tone Toshiyuki
Published: May 2005

Using the effective wavelength concept, it is derived theoretically that the reciprocal of the analyte‐line intensity is linearly correlated with the reciprocal of the weight fraction of the analyte. This linear relationship is substantiated experimentally in some liquid and fusion product samples. Two ways of application of the relationship in X‐ray fluorescence analysis and their advantages are also described. It is emphasized that if the relationship is used the construction of calibration curves is not required.
Space resolved x‐ray spectroscopy for tokamak
Authors: Fraenkel Benjamin S.
Published: May 2005

Space resolved X‐ray spectroscopy with a curved crystal X‐ray spectrometer for an extended source such as the Tokamak is discussed. Limits of resolution caused by instrumental broadening are shown, using various entrance apertures. Ion density distribution may be obtained by measurement of intensity variation along spectral lines. In order to obtain ion temperature distribution about the central plasma line in the Tokamak, a novel method is proposed. In this method reflection in the curved crystal takes place through the double reflection process. This is possible as practically no instrumental broadening is caused when using this method, while it reflects the radiation in a strictly space resolved mode.
K and L x‐ray emission intensities of some radionuclides
Authors: Verma H. R. , Pal Dharminder
Published: May 2005

The K and L x‐ray emission intensities per 100 disintegrations have been calculated for some radionuclides using the latest adopted data for gamma‐ray intensities, electron capture and internal conversion coefficients for the parent nuclides, fluorescence yield values, Coster–Kronig transition probabilities, average total number of primary L shell vacancies produced in the decay of K shell vacancies and emission rates for various shells and subshells for the daughter nuclei. The results are in good agreement with theoretical and experimental values for the K x‐ray intensities. There are no experimental results available to compare with the present calculations for the L x‐ray intensities; however, there is a marked discrepancy in the Lα and Lβ intensities available on the basis of theoretical estimates.
Polarized x‐ray spectra of α‐Fe2O3
Authors: Leiro J. A. , Dräger G. , Czolbe W.
Published: May 2005

The linearly polarized Fe K absorption and Fe Lα emission spectra of α‐Fe2O3 were measured. Also, the usual Fe K‐emission band is presented. These measurements are compared with results of multiplet theory and cluster calculations. The spectra are also compared with x‐ray photoemission and inverse photoemission data as well.
Measurement of x‐ray attenuation coefficients around K‐absorption edges using fe Kα x‐rays
Authors: Kerur B. R. , Thontadarya S. R. , Hanumaiah B.
Published: May 2005

The x‐ray mass attenuation coefficients were measured around the K‐absorption edges of elements in the range 16 ⩽ Z ⩽ 30 using Fe Kα x‐rays of energy 6.400 keV, which is the weighted average energy of Kα1 and Kα2 x‐ray components from the 57Co radioactive source. Kβ x‐rays were almost eliminated by the differential absorption technique. The small difference in energy between Kα1 and Kα2, 13 eV, was shown to be inconsequential by comparing the measured and theoretical values of μ/ρ for standard materials such as Al, Cu, Mo and Ta. The effect of fine structure of the K‐absorption edge on μ/ρ was elucidated by using the compounds of elements in the range 16 ⩽ Z ⩽ 30, containing one element with its K‐absorption edge energy (Ek) close to the incident photon energy (Ex). The results clearly indicate the validity of the theoretical mixture rule for all those compounds whose K edge is far away from the incident energy but show deviations of as much as 10% for the manganese compound whose K edge is 140 eV above Ex and about 12% for the chromium compound whose K edge is 410 eV below Ex. These deviations are attributed to the possible influence of resonance Raman scattering when the incident photon energy Ex is less than the edge energy and to the influence of EXAFS when Ex is more than the edge energy.
Method for quantitative XRF analysis of inhomogeneous thin specimens
Authors: Markowicz A. , Haselberger N. , Whai Zin Oo U.
Published: May 2005

A simple method for the quantitative XRF analysis of inhomogeneously loaded thin samples is described. Both the theoretical basis of the method and the results of an experimental test are presented.
Measurement of total photoelectric cross‐sections for 52.4 keV photons
Authors: Jahagirdar H. A. , Hanumaiah B. , Thontadarya S. R.
Published: May 2005

Accurate measurements (within 3.2%) of the total photoelectric cross‐sections of Ag, Sn and Ba for a 52.4 keV photon energy were made using an NaI(Tl) spectrometer system coupled to a 1K MCA in an extreme broad‐beam geometry configuration. The results were compared with their corresponding theoretical values and good agreement was obtained.
Vanadium metabolism in wild type and respiratory‐deficient strains of S. cerevisiae
Authors: Willsky Gail R. , Dosch Susan F.
Published: May 2005

Vanadium metabolism was studied in a wild type and respiratory‐deficient strains of S. cerevisiae. Inhibition of growth by vanadate [V(+5)], vanadate accumulation, and conversion of medium vanadate [V(+5)] to both cell‐associated and medium vanadyl [V(+4)] and vanadate [V(+5)] were compared. The growth of both the parental and respiratory‐deficient strains was inhibited by vanadate at concentrations greater than or equal to 1 mM. Both parental and respiratory‐deficient strains accumulated vanadate and converted medium vanadate to cellular vanadyl as detected using electron spin resonance (ESR). The accumulation of cell‐associated vanadyl was correlated with the loss of medium vanadate in both strains using a chemical assay. In contrast, the respiratory‐deficient strain showed a greater amount of a cell‐associated vanadate compound, as detected with vanadium‐51 nuclear magnetic resonance (51V‐NMR), than the wild strain or a representative respiratory‐competent vanadate‐resistant mutant. These data imply that mitochondrial function may be directly involved in vanadium metabolism.
Mechanism of inactivation of UDP‐glucose 4‐epimerase from Saccharomyces cerevisiac by D‐xylose and L‐arabinose
Authors: Cármenes Ricardo S. , Gascón Santiago , Moreno Fernando
Published: May 2005

In a previous paper (Cármenes et al., 1984) we reported that UDP‐glucose 4‐epimerase from Saccharomyces was inactivated both in vitro (Crude extracts) by L‐arabinose or D‐xylose. In this paper, we reported that pure epimerase requires the presence of UMP or UDP to be inactivated by sugars and that the inactivation is due to the reduction of the epimerase NAD+, which is essential for epimerase activity. The inactivation rate is directly proportional to epimerase and sugar concentrations and hyperbolically proportional to UMP concentration. In situ experiments made with permeabilized cells showed that epimerase is inactivated in the same way when it is inside the cell. In vivo studies showed that epimerase is inactivated to a smaller extent when 1% Dgalactose is present in the culture medium than when 1% ethanol is the main carbon source.
Characterization of plasma membrane H+‐ATPase from salt‐tolerant yeast Candida versatilis
Authors: Watanabe Yasuo , Yamaguchi Masahiro , Sakamoto Jun , Tamai Youichi
Published: May 2005

Plasma membrane was isolated from the salt‐tolerant yeast Candida versatilis and the ATPase in plasma membrane was characterized. The ATPase was a typical H+‐ATPase with similar properties to the Saccharomyces cerevisiae and Zygosaccharomyces rouxii enzymes. It was reacted with antibody (IgG) raised against S. cerevisiae plasma membrane H+‐ATPase. The ATPase activity was not changed by adding NaCl and KCl to the assay solutions, but was increased by NH, especially by ammonium sulfate. In vivo stimulation of ATPase activity was observed by the addition of NaCl into the culture medium, as observed in Z. rouxii. No in vivo activation of H+‐ATPase by glucose metabolism was observed in C. versatilis cells and the activity was independent of the growth phase, like Z. rouxii and unlike S. cerevisiae cells.
Role of the γ component of preprotoxin in expression of the yeast K1 killer phenotype
Authors: Zhu Yun‐Song , Kane Jeff , Zhang Xia‐Ying , Zhang Meng , Tipper Donald J.
Published: May 2005

K1 killer strains of Saccharomyces cerevisiae secrete a polypeptide toxin to which they are themselves immune. The α and β components of toxin comprise residues 45–147 and 234–316 of the 316‐residue K1 preprotoxin. The intervening 86‐residue segment is called γ. A 26‐residue signal peptide is removed on entry into the endoplasmic reticulum. The Kex2 protease excises the toxin components from the 290‐residue glycosylated protoxin in a late Golgi compartment. Expression of a cDNA copy of the preprotoxin gene confers the complete K1 killer phenotype on sensitive cells. We now show that expression of immunity requires that α component and the N‐terminal 31 residues of γ. An additional C‐terminal extension, either eight residues of γ or three of four unrelated peptides, is also required. Expression of preprotoxin terminating at the α C‐terminus, or lacking the γ N‐terminal half of γ causes profound but reversible growth inhibition. Inhibition is suppressed in cis by the same 31 residues of γ required for immunity to exocellular toxin in trans, but not by the presence of β. Both immunity and growth inhibition are alleviated by insertions in α that inactivate toxin. Inhibition is not suppressed by kex2, chc1 or kre1 mutations, by growth at higher pH or temperature, or by normal K1 immunity. Inhibition, therefore, probably does not involve processing of the α toxin component at its N‐terminus or release from the cell and binding to glucan receptors. Some insertion and substitution mutations in γ severely reduce toxin secretion without affecting immunity. They are presumed to affect protoxin folding in the endoplasmic reticulum and translocation to the Golgi.
Transcriptional studies on yeast SEC genes provide no evidence for regulation at the transcriptional level
Authors: Vahlensieck Yvonne , Riezman Howard , Meyhack Bernd
Published: May 2005

A number of proteins have been identified as components of the secretory pathway of Saccharomyces cerevisiae (SEC gene products). However, very little is known about the expression of these components and their regulation at the transcriptional level. In this study yeast cells were exposed to conditions that changed the secretory activity of the cells. The conditions analysed include the different stages of the cell cycle, overexpression of secretory proteins, and block of secretion and endocytosis. The effect of these conditions on the transcriptional expression levels of a number of SEC genes (SAR1, SEC1, SEC14, SEC17, SEC18, SEC23, SEC62, YPT1) was analysed. In summary, no major changes in transcriptional expression levels could be detected. From these results we conclude that the components of the secretory pathway are expressed constitutively and that no general regulation of transcription exists, that could adjust the expression level of the SEC genes to the secretory activity of the cells.
The effect of ethanol and specific growth rate on the lipid content and composition of Saccharomyces cerevisiae grown anaerobically in a chemostat
Authors: Arneborg Nils , Høy Carl‐Erik , Jørgensen O. B.
Published: May 2005

The effects of produced ethanol and specific growth rate on the lipid content and composition of Saccharomyces cerevisiae CBS 2806 were studied using anaerobic chemostat cultures. The cells adapted to increased concentrations of produced ethanol by increasing the proportion of ergosterol at the expense of lanosterol, by increasing the proportion of phosphatidylinositol at the expense of phosphatidylcholine, and by increasing the amount of C18:0 fatty acids in total phospholipids at the expense of C16:0 fatty acids. The produced ethanol had no effect on the phospholipid content nor on the proportion of unsaturated fatty acids in the phospholipids.

The specific growth rate had no effect on the phospholipid content, the sterol composition, the phospholipid composition, the fatty acid composition of total phospholipids, or on the proportion of unsaturated fatty acids in the phospholipids of S. cerevisiae. It was not possible to separate the effects of produced ethanol and growth rate on the ergosterol content of the chemostat‐grown S. cerevisiae cells.
Chemischer Transport fester Lösungen. 18 [1] Der Chemische Transport von ZnIn2S4, ZnIn2Se4 und ZnIn2S4−xSex‐Mischphasen
Authors: Locmelis S. , Milke E. , Binnewies M. , Gruhl S. , Vogt C.
Published: May 2005

Chemical Vapor Transport of Solid Solutions. 18. [1] Chemical Vapor Transport of ZnIn2S4, ZnIn2Se4 and ZnIn2S4−xSex‐mixed Crystals

By means of CVT methods using iodine as transport agent (725 → 675 °C) ZnIn2S4, ZnIn2Se4 und ZnIn2S4−xSex‐mixed phases could be obtained. Mass spectrometric investigations show the formation of ZnI2(g) and InI3(g) are due to the transport reaction. The transport process leads to a significant enrichment of sulphur.
Chemischer Transport fester Lösungen. 19 [1] Der Chemische Transport von Mischphasen im System Ga2S3/Ga2Se3
Authors: Hotje U. , Wartchow R. , Milke E. , Binnewies M.
Published: May 2005

Chemical Vapor Transport of Solid Solutions. 19, Chemical Vapor Transport of Mixed Phases in the Systems Ga2S3/Ga2Se3

By means of CVT methods using iodine as transport agent (950 → 800 °C) in the system Ga2S3/Ga2Se3 mixed crystals could be prepared. The miscibility gap, given in the literature, could not be observed, but the phase transition between a monoclinic (Ga2S3) and cubic (Ga2Se3) phase. The powder diffraction patterns of the mixed phases with the compositions Ga2S2,4Se0,6 und Ga2S0,6Se2,4 can be indexed hexagonally. The transport process occurs congruently. Thermochemical calculations as well as mass spectrometric investigations show that GaI3 (solid: Ga2S3) and GaI/GaI3 (Ga2Se3) are the gaseous species, due to the transport process. A congruent transport of all mixed phases in this system could be observed.
M(S)2(I)2 (M=Zn, Cd) and Hg(S)3I Coordination Environment of Transition Metal Complexes – Synthesis, Spectral, and Single Crystal X‐ray Structural Investigations
Authors: Saravanan M. , Prakasam B. Arul , Ramalingam K. , Bocelli G. , Cantoni A.
Published: May 2005

Three new transition metal complexes [Zn(bipyrtds)I2](1), [Cd(bipyrtds)I2] (2) and [Hg(pipdtc)I](3) (where bipyrtds = bipyrrolidine thiuamdisulfide and pipdtc = piperidinecarbodithioate) were prepared by the reaction of the corresponding biscarbodithioates with iodine and were characterized by elemental analysis, IR and NMR spectra. The structures of all the three complexes were determined by single crystal X‐ray crystallography. Compounds 1 and 2 contain four coordinated metal atoms and both ZnII and CdII complexes are isostrucutral. Interestingly, complex 3 was found to contain effectively four coordinated mercury atom as a dimer with a relatively long Hg‐S (3.084Å) bond. The IR studies are in keeping with the observed thioureide distances. 1H NMR spectra of 1 and 2 show clear differences in environments of α‐ and β‐CH2 protons. However, in 1 a broad signal was observed at 4.02 ppm for α‐protons and a multiplet at 2.10 for β‐protons. For 2, two triplets appeared at 4.26 and 4.03 ppm for α‐protons and two quintets appeared in the range of 2.18 and 2.28 ppm for β‐protons. Complex 3 gave three sets of signals. Variation of stereochemical environment with respect to α and β protons of the rings is very clearly observed in the NMR spectra.
Structure Investigations on 4‐Halo‐1,2,3,5‐dithiadiazolyl Radicals XCNSSN• (X = F, Cl, Br): The Shortest Intradimer S···S Distance in Dithiadiazolyl Dimers
Authors: Knapp Carsten , Lork Enno , Gupta Kumar , Mews Rüdiger
Published: May 2005

Crystals of the 4‐halo‐1,2,3,5‐dithiadiazolyl radicals (X = F, Cl, Br) were obtained by sublimation at 80 °C and 10−2 Torr, and the structures were determined by X‐ray diffraction. The fluoro derivative crystallizes as a cisoid dimer in the space group P21/n, whereas the chloro and bromo derivatives crystallize isomorphous as twisted dimers in the space group C2/c. The chloro and bromo derivatives show the shortest intradimer S···S contacts of all known 1,2,3,5‐dithiadiazolyl dimers. In addition the obtained structure of ClCN2S2• represents the fifth polymorph of ClCN2S2• characterized by X‐ray crystallography. The structures and the packing including secondary interactions are discussed.
Structural Patterns and Dimensionality in Magnesium Borophosphates: The Crystal Structures of Mg2(H2O)[BP3O9(OH)4] and Mg(H2O)2[B2P2O8(OH)2]·H2O
Authors: Ewald Bastian , Öztan Yigit , Prots Yurii , Kniep Rüdiger
Published: May 2005

Hydrothermal investigations in the system MgO/B2O3/P2O5(/H2O) yielded two new magnesium borophosphates, Mg2(H2O)[BP3O9(OH)4] and Mg(H2O)2[B2P2O8(OH)2]·H2O. The crystal structures were solved by means of single crystal X‐ray diffraction. While the acentric crystal structure of Mg2(H2O)[BP3O9(OH)4] (orthorhombic, P212121 (No. 19), a = 709.44(5) pm, b = 859.70(4) pm, c = 1635.1(1) pm, V = 997.3(3) × 106 pm3, Z = 4) contains 1D infinite chains of magnesium coordination octahedra interconnected by a borophosphate tetramer, Mg(H2O)2[B2P2O8(OH)2]·H2O (monoclinic, P21/c (No. 14), a = 776.04(5) pm, b = 1464.26(9) pm, c = 824.10(4) pm, β = 90.25(1)°, V = 936.44(9) × 106 pm3,Z = 4) represents the first layered borophosphate with 63 net topology. The structures are discussed and classified in terms of structural systematics.
Crystal Structure of Cesium Dihydrotrifluoride, CsH2F3. Refinement of the Crystal Structures of NMe4HF2 and NMe4H2F3
Authors: Troyanov S. I. , Morozov I. V. , Kemnitz E.
Published: May 2005

Single crystals of (NMe4)(HF2) were obtained during attempted recrystallization of NMe4F from fluoroolefin. X‐ray diffraction data show that (NMe4)(HF2) crystallizes in the orthorhombic space group Pmmn with unit cell dimensions a = 6.535(2), b = 8.688(3), and c = 5.333(2) Å. The symmetric and virtually linear HF2 anions exhibit a short F···F distance of 2.256(2) Å. The both crystal structures of (NMe4)(H2F3) (orthorhombic, Pbca, a = 8.509(1), b = 11.273(2), and c = 14.880(2) Å) and CsH2F3 (orthorhombic, P212121, a = 7.345(3), b = 9.126(4), and c = 11.444(4) Å) contain dihydrogentrifluoride anions, H2F3−, which have a bent shape and F···F distances of 2.30‐2.34Å.
Nitridorhenium(V) Complexes with 1,3,4‐Triphenyl‐1,2,4‐triazol‐5‐ylidene
Authors: Braband H. , Neubacher S. , Grosskopf S. , Abram Ulrich
Published: May 2005

[ReNCl2(PPh3)2] and [ReNCl2(PMe2Ph)3] react with the N‐heterocyclic carbene (NHC) 1,3,4‐triphenyl‐1,2,4‐triazol‐5‐ylidene (HLPh) under formation of the stable rhenium(V) nitrido complex [ReNCl(HLPh)(LPh)], which contains one of the two NHC ligands with an additional orthometallation. The rhenium atom in the product is five‐coordinate with a distorted square‐pyramidal coordination sphere. The position trans to the nitrido ligand is blocked by one phenyl ring of the monodentate HLPh ligand. The Re–C(carbene) bond lengths of 2.072(6) and 2.074(6) Å are comparably long and indicate mainly σ‐bonding between the NHC ligand and the electron deficient d2 metal atom.

The chloro ligand in [ReNCl(HLPh)(LPh)] is labile and can be replaced by ligands such as pseudohalides or monoanionic thiolates such as diphenyldithiophosphinate (Ph2PS2−) or pyridine‐2‐thiolate (pyS−). X‐ray structure analyses of [ReN(CN)(HLPh)(LPh)] and [ReN(pyS)(HLPh)(LPh)] show that the bonding situation of the NHC ligands (Re–C(carbene) distances between 2.086(3) and 2.130(3) Å) in the product is not significantly influenced by the ligand exchange. The potentially bidentate pyS− ligand is solely coordinated via its thiolato functionality.

Hydrogen atoms of each one of the phenyl rings come close to the unoccupied sixth coordination positions of the rhenium atoms in the solid state structures of all complexes. Re–H distances between 2.620 and 2.712Å do not allow to discuss bonding, but with respect to the strong trans labilising influence of “N3−”, weak interactions are indicated.
Crystal Structure of Rubidium Tetraiodothallate(III) Dihydrate, RbTlI4·2H2O
Authors: Rieger Franziska , Mudring Anja‐Verena
Published: May 2005

The crystal structure of RbTlI4·2H2O (cubic, ${\rm Fm}{\bar 3}\rm c$, Nr. 226, Z = 24, a = 1993.5(2) pm, 327 unique reflections with Io > 2σ(Io), R1 = 0.0305, wR2 = 0.0702, GooF = 1.1199, T = 298(2) K) is characterized by an ReO3 analogous arrangement of rubidium centered [TlI4] tetrahedra. The cuboctahedral cavities of this structure are filled with crystal water molecules and additional disordered rubidium cations.
Zum Chemischer Transport ternärer Übergangsmetall‐ und Erdalkaliwolframate MWO4 mit Chlor
Authors: Steiner Udo
Published: May 2005

On the Chemical Vapor Transport of Ternary Transition Metal‐ and Earth Alkaline Tungstates MWO4 with Chlorine

The chemical vapor transport of transition metal tungstates MWO4 (M=Mn, Co, Ni, Cu, Zn, Cd) was investigated in dependence on mean transport temperature (923 K to 1223 K) and amount of transport agent Cl2. All tungstates migrate in a temperature gradient ΔT = 100 K from the region of higher temperature to the lower temperature with migration rates of 0.5 to 8 mg/h depending on experimental conditions. The transport behaviour was determined by continuous measurement of mass change during the transport experiments. The results were compared to thermo chemical calculations and the influence of moisture content discussed in detail. MgWO4 migrates under the influence of Cl2 in a temperature gradient 1273 K to 1173 K (migration rate 0.7 mg/h), CaWO4 and SrWO4 in a temperature gradient 1423 K to 1323 K (migration rate <0.1 mg/h).
γ‐HIO3 – a Metastable, Centrosymmetric Polymorph of Iodic Acid
Authors: Fischer Andreas , Lindsjö Martin
Published: May 2005

From solutions of chromium(III) perchlorate and periodic acid, single crystals of γ‐HIO3 were obtained and characterized by single‐crystal X‐ray diffraction, Raman spectroscopy and thermal analysis. The compound crystallizes in the orthorhombic crystal system, space group Pbca (a = 563.92, b = 611.10, c = 1507.16 pm). The structure is built up by dimers (HIO3)2, which are formed by hydrogen bonds. The crystals are metastable and transform into the stable modification, α‐HIO3, within a couple of weeks.
Hyperacidity and hypergastrinemia following extensive intestinal resection
Authors: Meyers William C. , Jones R. Scott
Published: May 2005

Increased gastric acid secretion occurs after extensive intestinal resection in man, dog, rat, and monkey. Hypergastrinemia has been observed in patients with short gut syndrome and appears to accompany the hyperacidity after intestinal resection in dog, rat, and monkey. Postresectional hypergastrinemia is caused by increased release of gastrin and/or decreased degradation of the hormone. Other hormonal changes after extensive resection include increased insulin, GIP, pancreatic glucagon, and decreased enteroglucagon.
Clinical studies with gastric inhibitory polypeptide
Authors: Brown John C. , Otte Sue
Published: May 2005

Intravenous infusion of porcine GIP in man induces insulin release when a degree of hyperglycemia is present. This glucose‐dependent insulinotropic response occurs when a dose of GIP is administered to obtain circulating levels of approximately 1 ng/ml, a physiologic level that can be achieved by the ingestion of glucose or corn oil or a mixed meal. Serum GIP was measured by radioimmunoassay, and the single antiserum used in all the described studies measures 2 immunoreactive forms of GIP.

In patients with chronic pancreatitis receiving an oral glucose load or a mixed liquid test meal, GIP levels have been shown to be exaggerated. Similar elevated responses have been observed in obese patients and in maturity onset diabetes. A reduced GIP response has been seen in patients with celiac disease.

A physiologic role for GIP in the enteroinsular axis has been established. However, involvement of the hormone in pathophysiologic situations is equivocal.
Resection of the pancreas for acute hemorrhagic and necrotizing pancreatitis
Authors: Autio Ville , Juusela Eero , Lauslahti Kalevi , Markkula Hannu , Pessi Teuvo
Published: May 2005

The role of surgery in the treatment of acute hemorrhagic or necrotizing pancreatitis is discussed on the basis of a series of 996 patients with all types of acute pancreatitis who were treated in the years 1967–1976. Pancreatic resection was performed in 29 patients with hemorrhagic or necrotizing pancreatitis during the past 3 years. The extent of resection ranged from 60 to 100% of the pancreas. Eight patients died, for a mortality rate of 28%. Eight of 21 surviving patients developed diabetes requiring substitution therapy. During a follow‐up period of 6 to 36 months, 17 patients were able to resume work, 3 are still convalescing, and 1 has retired.
Diagnosis and surgical treatment of “H‐Type” tracheoesophageal fistulas
Authors: Lam Conrad R.
Published: May 2005

Four cases of H‐type tracheoesophageal fistula are reported. The patients all had chronic aspiration from the esophagus. Although serious symptoms were present in all, definitive diagnoses were not made until the patients had reached 1, 6, 12, and 50 years of age, because ordinary radiologic methods failed to establish the diagnosis. The angulation of the fistula usually prevents contrast medium in the esophagus from entering the trachea, especially with the subject upright. On the other hand, air easily passes from the trachea to the esophagus, eventually producing megaesophagus which may be confused with the picture of achalasia. An ill‐advised Heller esophagomyotomy was done on 1 patient. All 4 patients eventually had successful closure of the fistulas. Three operations were by the transthoracic route, and 1 high fistula in an infant was closed through a cervical approach.
The influence of oestrogen‐deficiency and ACE inhibition on the progression of myocardial hypertrophy in spontaneously hypertensive rats
Authors: Martin van Eickels , Rolf Schreckenberg , Doevendans Pieter A. , Meyer Rainer , Grohé Christian , Schlüter Klaus‐Dieter
Published: May 2005

Background:

ACE inhibitors are widely used to antagonize the biological activity of angiotensin II in hypertensive heart disease. Oestrogen reduces angiotensin type 1 receptor expression, and thereby modifies angiotensin signalling.

Aim:

To investigate the interaction of oestrogen status and ACE inhibition on the development of left ventricular hypertrophy and expression of transforming growth factor (TGF)‐β1 in female spontaneously hypertensive rats (SHR).

Methods and results:

Intact female SHR, ovariectomised SHR, and ovariectomised SHR with 17β‐oestradiol (E2) replacement therapy were either treated with placebo or the ACE inhibitor moexiprilat. Blood pressure, left ventricular hypertrophy, and expression of TGF‐β1 and TGF‐β1‐regulated genes were investigated. ACE inhibition reduced blood pressure in all groups. When normalised to blood pressure, a significant reduction in hypertrophy was found in ovariectomised animals receiving E2. Expression of TGF‐β1 was increased in all three groups treated with the ACE inhibitor, with top levels in ovariectomised animals. Moreover, expression of ornithine decarboxylase (ODC), an adrenoceptor dependent gene, downstream of TGF‐β1, was up‐regulated upon ACE inhibition, except in animals which were ovariectomised and oestrogen supplemented. Parathyroid hormone‐related peptide, a growth factor negatively regulated by TGF‐β1, was down‐regulated in all animals receiving the ACE inhibitor.

Conclusion:

ACE inhibition modulated TGF‐β1 and TGF‐β1 dependent genes. Oestrogen deficiency alone did not influence the progression of cardiac hypertrophy in this model of female SHR.
Ultra‐short metformin pretreatment for clomiphene citrate‐resistant polycystic ovary syndrome
Authors: Hwu Y.M. , Lin S.Y. , Huang W.Y. , Lin M.H. , Lee R.K.K.
Published: May 2005

Objective: To evaluate the effect of ultra‐short (12 days) metformin pretreatment in clomiphene‐citrate (CC) resistant polycystic ovary syndrome (PCOS). Method: Eighty women with CC‐resistant PCOS were randomly allocated to metformin pretreatment or usual treatment. Forty women received 1500 mg metformin daily for 12 days, followed by clomiphene 150 mg daily for 5 days along with metformin. Forty women (control group) received the same dose of clomiphene but no metformin pretreatment. Results: In the metformin group, 17 (42.5%) women ovulated, and 6 (15%) conceived. In the control group, 5 (12.5%) women ovulated but none conceived. Compared with the control group, the metformin group had significantly higher ovulation (P = 0.03) and pregnancy rates (P = 0.026). Conclusion: Twelve days of metformin pretreatment improves ovulation and pregnancy rates in women with CC‐resistant PCOS.
Immunolocalization of collagen types in the subsynovial connective tissue within the carpal tunnel in humans
Authors: Oh Jinrok , Zhao Chunfeng , Amadio Peter C. , An Kai‐Nan , Zobitz Mark E. , Wold Lester E.
Published: May 2005

The tenosynovium within the carpal tunnel consists of a single layer of synovial cells, which lines the bursae within the carpal tunnel, and the subsynovial connective tissue (SSCT), which contains the tendon vasculature and other structural elements. In this study, we used immunogold labeling to localize collagen types within the SSCT in three cadaver specimens and three patients with carpal tunnel syndrome. Positive labeling for collagen types I, III and VI was found with immunoelectron microscopy. Collagen types I and III were codistributed within the SSCT. Type VI was primarily located in microfibrillar structures between collagen bundles, between elastin and collagen bundles and between collagen bundles and cells. There was no difference in the distribution of collagen types when comparing cadaver specimens and carpal tunnel patients. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
DISCRIMINATION, OPPORTUNITY, AND MIDDLE-CLASS SUCCESS IN EARLY COMMUNIST HUNGARY
Authors: MARK JAMES
Published: May 2005

This article explores the middle-class response to life under the early Communist state in Hungary. It is based on an oral history of the Budapest bourgeoisie, and challenges some of the dominant indigenous representations of the central European middle class as persecuted victims who were forced into ‘internal exile’ by the Stalinist state. Despite being officially discriminated against as ‘former exploiters’, large numbers achieved educational and professional success. Their skills were increasingly needed in the rapid modernization of the 1950s, and the state provided them with semi-official opportunities to remake themselves into acceptable Communist citizens. Middle-class testimony revealed how individuals constructed politically appropriate public personas to ensure their own upward mobility; they hid aspects of their pasts, created ‘class conscious’ autobiographies, and learnt how to demonstrate sufficient political loyalty. The ways in which individuals dealt with integrating into a system which officially sought to exclude them and which many disliked ideologically is then examined. In order to ‘cope with success’, respondents in this project invented new stories about themselves to justify the compromises they had made to ensure their achievements. These narratives are analysed as evidence of specifically Communist middle-class identities.
‘The present position of economics’ by Alfred Marshall
Authors: HODGSON GEOFFREY M.
Published: May 2005

Alfred Marshall was elected to the Chair of Political Economy at the University of Cambridge in December 1884. He gave his inaugural lecture on ‘The present position of economics’ on 24 February 1885 (Groenewegen, 1995: ch. 10). An abridged version of this lecture is presented below.
The Atlantic Equatorial Undercurrent: PIRATA observations and simulations with GFDL Modular Ocean Model at CPTEC
Authors: Giarolla Emanuel , Nobre Paulo , Malagutti Marta , Pezzi Luciano Ponzi
Published: May 2005

This paper shows the Atlantic Equatorial Undercurrent (EUC) revealed by a PIRATA ADCP during 2002 at 0°N, 23°W and simulated by an eddy‐resolving ocean general circulation model (MOM) forced by NCEP/NCAR reanalysis wind stresses. The PIRATA data revealed the shallowing of the EUC between January and May, concurrently with the reversal of the easterly trades to westerly, and the deepening of the EUC from May to December. Empiric Orthogonal Function (EOF) analysis shows two main components; the first mode, explaining 63.7% of the total variance, represents the main seasonal variation of the undercurrent during 2002, while the second mode, explaining 19.9% of the variance, represents higher frequency variability occurring in the EUC core, from 60 to 80 m. All model experiments were able to reproduce this variability, and the best one was chosen objectively using EOF and joint EOF analysis techniques.
Seismic imaging of the crust and upper mantle using regularized joint receiver functions, frequency–wave number filtering, and multimode Kirchhoff migration
Authors: Wilson David , Aster Richard
Published: May 2005

Receiver functions provide an indispensable tool for producing discontinuity images of the crust and upper mantle from teleseismic earthquake arrivals. However, image quality can be significantly compromised by instabilities inherent in the deconvolution process and by irregularities in data coverage driven by source and/or receiver geometries. We present receiver function estimation and prestack migration techniques which both reduce receiver function deconvolution instability and produce regularized, multimode receiver function images. The receiver function estimation technique exploits frequency–wave number filtering methods using frequency–pseudowave number domain filtering of gathers to enhance arrivals with consistent moveout characteristics. Synthetic tests confirm robust recovery of features in the presence of high noise levels. To process regularized receiver functions into accurate images of the subsurface seismic scattering potential, we employ a regularized Kirchhoff migration that migrates both direct and reverberated P‐to‐S converted modes to their correct subsurface locations. The subsequent images can be stacked to mute mismigrated modes. Synthetic studies and model resolution tests demonstrate that this methodology is well suited to irregularly spaced stations and uneven data coverage and does not require the recording of a single earthquake at multiple stations.
Intense warming and salinity modification of intermediate water masses in the southeastern corner of the Bay of Biscay for the period 1992–2003
Authors: González‐Pola Cesar , Lavín Alicia , Vargas‐Yáñez Manuel
Published: May 2005

The evolution of the intermediate water masses within the southeastern corner of the Bay of Biscay is studied from the shelf edge and slope stations of a hydrographic standard section northward from Santander (43°30′/43°54′N, 3°47′W). The section was sampled monthly from 1991 to autumn 2003 with some gaps more frequent in the early stages due to weather conditions. Data were systematically collected up to a 1000 m depth (or to the maximum depth at the shallower stations) showing a detailed picture of the variability in water masses below the mixing layer. Eastern North Atlantic Central Water has warmed as a consequence of continuous deepening of the isopycnal levels. Changes in water properties at fixed isopycnal levels are less relevant and highly biased by a 1998 positive peak in temperature and salinity. The warming trend found is 0.032°C per year on average. On the other hand, the Mediterranean Water has been modified along isopycnals (variations 10 times greater than those due to isopycnal displacement) increasing progressively both temperature and salinity for the period 1994–2001. The values found are around 0.020°C per year for temperature and 0.005 for salinity. As a final picture, all water masses below the mixing layer and down to a 1000 m depth in the southern Bay of Biscay have warmed up during the last decade at rates from two to six times greater than the those accepted for the North Atlantic during the last half century.
Simulation of turbulent exchange processes in summertime leads
Authors: Skyllingstad Eric D. , Paulson Clayton A. , Pegau W. Scott
Published: May 2005

Ice‐ocean heat exchange in polar leads was examined using a large‐eddy simulation model coupled to a slab ice model. Simulations were performed using an idealized square domain for a range of lead sizes, surface wind stress (0.05–0.1 N m−2), and lead temperature/salinity profiles. Particular emphasis was placed on understanding the role of fresh water in leads and how stratification controls the heat budget and ice edge melting rate. With uniform initial conditions we found that solar heating was not strong enough to develop lead freshening via ice edge melting; even weak winds (0.02 N m−2) generated circulations that maintained a well‐mixed lead. In the weak wind case, adding a fresh water flux representative of surface melt runoff provided enough additional stratification so that the lead water became isolated from the rest of the simulated ocean boundary layer. However, stronger winds (0.1 N m−2) prevented the fresh water layer from forming. Experiments initialized with temperature/salinity profiles similar to observed cases (fresh water layer capping the lead) demonstrated that lateral melting rates increase with expanding lead size, agreeing with simple heat balance calculations for a square lead without vertical mixing. However, with stronger winds, lateral melting rates decreased because of greater turbulent mixing of cold water from beneath the fresh layer. Inspection of the lead circulation indicated that the strongest melting occurred where the ice edge currents were the largest. Overall, melting fluxes for a 24 m2 lead ranged from 200 to 400 W m−2, depending on the wind speed. Without the fresh layer, fluxes ranged from 50 to 60 W m−2, suggesting that fresh water stratification can have a dominate role in controlling ice edge melting.
Frequency dependence of scattering from the cold‐temperate transition surface in a polythermal glacier
Authors: Pettersson Rickard
Published: May 2005

Radar surveys of the cold‐temperate transition in polythermal glaciers have been used to investigate the polythermal structure, as well as the stability of the temperature regime, in glaciers. The mapping is based on the detection of small water‐filled pockets present in the temperate ice beneath the cold surface layer. I compare radar profiles recorded at different frequencies on a polythermal glacier to show that the apparent depth to the cold‐temperate transition reflection at a center frequency of 155 MHz is significantly greater than that detected at frequencies above 345 MHz. This increase appears to be the result of a reduction of scattering efficiency from the uppermost part of the temperate ice, as the theory of electromagnetic scattering from small objects indicates a strong decrease in scattering efficiency from objects much smaller than the wavelength of the incident wave. Thus I interpret this apparent depth increase to indicate that the average radii of the water pockets of the cold‐temperate transition is on a subdecimeter scale. Spatial variation in the difference between cold‐temperate transition depths at 155 MHz and higher frequencies may arise from spatial variations in size or the number density of scatterers.
Multipulse and double‐pulse velocities of Scandinavian Twin Auroral Radar Experiment (STARE) echoes
Authors: Uspensky M. , Koustov A. , Sofieva V. , Amm O. , Kauristie K. , Schmidt W. , Nielsen E. , Pulkkinen T. , Pellinen R. , Milan S. , Pirjola R.
Published: May 2005

The Scandinavian Twin Auroral Radar Experiment (STARE) coherent radars are a powerful instrument for studying auroral zone plasma convection. In recent years the STARE radars have been collecting both double‐pulse (DP) and multipulse (MP) data to measure the Doppler velocity of auroral echoes. We assess here DP‐MP measurements for eight events covering 28 hours of operation. More often, there is a reasonable agreement between the DP and MP velocities. Exceptions are afternoon‐evening observations for which the Finland radar DP velocity is nearly half the MP velocity obtained through fitting of the autocorrelation function of a received signal (ACF‐FIT), although the DP and MP1 (first lag) velocities are in reasonable agreement. We demonstrate that for periods with strong differences between the DP and MP ACF‐FIT velocities the spectra are strongly asymmetric, and the phase angle–lag number dependence is nonlinear with a slower rate of angle increase at small‐number lags (<3) and a faster rate of angle increase at larger‐number lags. Contrary to the DP velocity, the MP ACF‐FIT velocity (obtained in some cases without one or two first‐lag data) is fairly close to the spectral power peak and power‐weighted (over spectrum) velocity. In an attempt to understand the DP‐MP velocity differences, we consider the role of the asymmetry of observed spectra and show that it can explain the discrepancies but only partially. As another potentially important effect, we consider the possibility of weak, but not negligible, cross‐range correlation between the signals coming from the target and aliasing volumes that are closely spaced for the current STARE mode of operation.
Observing the open‐closed boundary using cusp‐latitude magnetometers
Authors: Ables S. T. , Fraser B. J.
Published: May 2005

A new ground‐based diagnostic of reconnection at the magnetopause using ULF waves is presented, and we give an example day in which the dynamics of the open‐closed boundary (OCB) are clearly observed. The diagnostic is based on data from two close (∼110 km), magnetic azimuthally spaced magnetometer sites (Davis and Zhongshan, Antarctica). During average IMF conditions Davis passes just equatorward of the last closed field lines in the dayside magnetosphere, and cross‐phase measurements indicate propagation away from local magnetic noon (LMN) as expected for the Kelvin‐Helmholtz Instability (KHI) acting at the magnetopause. During times when IMF Bz < −2 nT intervals of broadband activity appear, with the azimuthal component of propagation directed towards noon. Statistical analysis shows a correlation between the negative magnitude of IMF Bz and cross‐phase measurements ±2–6 hours from LMN. We conclude that under the right conditions, reconnection signatures can be identified in magnetometer data superimposed on the KHI‐like propagation signatures of the last closed field lines.
Electron density, exchange-correlation density, and bond characterization from the perspective of the valence-bond theory. I. Two simple analytical cases
Authors: Rincón Luis , Alvarellos J. E. , Almeida Rafael
Published: May 2005

In this work, using a valence-bond wave function we obtain analytical expressions for the first- and second-order reduced density matrices of two simple, but quite representative, cases of diatomic molecular systems, namely, H2 and LiH. A detailed study of their exchange-correlation density is performed for both equilibrium and nonequilibrium internuclear distances, discriminating the parallel- and antiparallel-spin contributions. The results show that the behavior of the exchange-correlation density clearly changes with the character of the bond, making it possible to obtain a good deal of information regarding the type of the bond interaction.
Does coarsening begin during the initial stages of spinodal decomposition?
Authors: Rappl Timothy J. , Balsara Nitash P.
Published: May 2005

The initial stages of spinodal decomposition were studied by subjecting a critical blend of model polyolefins to a pressure quench and monitoring the evolution by time-resolved small angle neutron scattering. Contrary to the predictions of the widely accepted Cahn–Hilliard–Cook theory, we demonstrate that coarsening of the phase-separated structure begins immediately after the quench and occurs throughout the initial stages of spinodal decomposition.
Measurement and modeling of a diamond deposition reactor: Hydrogen atom and electron number densities in an Ar∕H2 arc jet discharge
Authors: Rennick C. J. , Engeln R. , Smith J. A. , Orr-Ewing A. J. , Ashfold M. N. R. , Mankelevich Yu. A.
Published: May 2005

A combination of experiment [optical emission and cavity ring-down spectroscopy (CRDS) of electronically excited H atoms] and two-dimensional (2D) modeling has enabled a uniquely detailed characterization of the key properties of the Ar∕H2 plasma within a ⩽10-kW, twin-nozzle dc arc jet reactor. The modeling provides a detailed description of the initial conditions in the primary torch head and of the subsequent expansion of the plasma into the lower pressure reactor chamber, where it forms a cylindrical plume of activated gas comprising mainly of Ar, Ar+, H, ArH+, and free electrons. Subsequent reactions lead to the formation of H2 and electronically excited atoms, including H(n=2) and H(n=3) that radiate photons, giving the plume its characteristic intense emission. The modeling successfully reproduces the measured spatial distributions of H(n>1) atoms, and their variation with H2 flow rate, FH20. Computed H(n=2) number densities show near-quantitative agreement with CRDS measurements of H(n=2) absorption via the Balmer-β transition, successfully capturing the observed decrease in H(n=2) density with increased FH20. Stark broadening of the Balmer-β transition depends upon the local electron density in close proximity to the H(n=2) atoms. The modeling reveals that, at low FH20, the maxima in the electron and H(n=2) atom distributions occur in different spatial regions of the plume; direct analysis of the Stark broadening of the Balmer-β line would thus lead to an underestimate of the peak electron density. The present study highlights the necessity of careful intercomparisons between quantitative experimental data and model predictions in the development of a numerical treatment of the arc jet plasma. The kinetic scheme used here succeeds in describing many disparate observations—e.g., electron and H(n=2) number densities, spatial distributions of optical emission from the plume, the variation of these quantities with added flow of H2 and, when CH4 is added, absolute number densities and temperatures of radicals such as C2 and CH. The remaining limitations of the model are discussed.
Transport of a liquid water and methanol mixture through carbon nanotubes under a chemical potential gradient
Authors: Zheng Jie , Lennon Erin M. , Tsao Heng-Kwong , Sheng Yu-Jane , Jiang Shaoyi
Published: May 2005

In this work, we report a dual-control-volume grand canonical molecular dynamics simulation study of the transport of a water and methanol mixture under a fixed concentration gradient through nanotubes of various diameters and surface chemistries. Methanol and water are selected as fluid molecules since water represents a strongly polar molecule while methanol is intermediate between nonpolar and strongly polar molecules. Carboxyl acid (–COOH) groups are anchored onto the inner wall of a carbon nanotube to alter the hydrophobic surface into a hydrophilic one. Results show that the transport of the mixture through hydrophilic tubes is faster than through hydrophobic nanotubes although the diffusion of the mixture is slower inside hydrophilic than hydrophobic pores due to a hydrogen network. Thus, the transport of the liquid mixture through the nanotubes is controlled by the pore entrance effect for which hydrogen bonding plays an important role.