bluuebunny/crossref_metadata_2025 huggingface dataset:
Radical cations of precursor compounds for organic conductors derived from carbohydrates: An ESR study
Authors: Scholz Markus , Gescheidt Georg , Schöberl Ulrich , Daub Jörg
Published: May 2005

The radical cations of two electron donors containing two 1,3‐dithiol moieties were characterized by the use of ESR/ENDOR/general TRIPLE spectroscopy. The spin population resides mainly in the central part of the molecules. The g‐factors are correlated with the 33S coupling constants, which are determined from satellite lines.
ESR measurement of translational diffusion constants
Authors: Fawthrop Susan A. , Gillies Duncan G. , Sutcliffe Leslie H. , Symms Mark R.
Published: May 2005

ESR spectroscopy can be used to measure the translational diffusion constants of spin probes in a variety of media using a capillary method. Following preliminary work, it has been possible to improve upon the accuracy of determining diffusion constants in two ways. Both methods require an experimental measurement of the resonant cavity sampling profile. In the first procedure, this cavity profile is convolved with a trial Gaussian distribution and the result is compared with the experimental data obtained from the ESR measurements; the diffusion constant is then determined by graphical optimization. The second method is a graphical one based on a knowledge of the experimental diffusion profile and the cavity sampling profile. Both methods have been shown to give similar results but the second less rigorous corrected‐zero method is generally simpler to apply. For a medium such as water, it takes several days to acquire the necessary experimental data but the time taken to carry out the experiment can be shortened (or slower rates of diffusion can be measured) by using a shielded resonant cavity.
Synthesis and ESR of a nitroxide biradical of approximate D2h symmetry
Authors: Fabre Claude , Gambarelli Serge , Jaouen Daniel , Rassat André , Brunel Louis‐Claude , Chachaty Claude
Published: May 2005

A nitroxide biradical 2,6‐dioxy‐2,6‐diaza‐1,1,3,3,5,5,7,7‐octamethyldicyclopentano[b;e]pyridine (1) and the corresponding monoradical (2‐oxy‐6‐hydroxy) were prepared starting from 2,2,5,5‐tetramethyl‐3‐oxopyrrolidine by successive condensation with formaldehyde (KOH) or DMF (K in THF), NH4OAc and oxidation (Na2WO4‐H2O2). In ethanol, biradical 1 shows a quintet (|J| ≫ |aN| = 14.6 G). In frozen ethanol solution, the experimental spectra (X‐band at 120 K and 240 GHz at 7, 15 and 25 K) can be computer simulated with the following parameters: D = −64 G; E = 1 G; gxx = 2.0093; gyy = 2.0064; gzz = 2.0020; Axx = Ayy = 8 G; Azz = 32.2 G. From the temperature dependence of the high‐field spectra, D is found to be negative.
Mobility of radicals in zeolite catalysts: Molecular motion studied by muon spectroscopy
Authors: Rhodes Christopher J. , Butcher Estelle C. , Morris Harry , Reid Ivan D.
Published: May 2005

Activation parameters for the surface dynamics of radicals produced by the addition of muonium to the unsaturated organic substrates cyclopentene, benzene, tetramethylethylene [2,3‐dimethylbut‐2‐ene (TME)] and 2,3‐dimethylbuta‐1,3‐diene (DMBD) adsorbed in the zeolites Na‐mordenite and NaX and on silica have been determined by means of transverse‐field muon spin rotation spectroscopy. This allows the study of the influence of adsorption by the different surfaces on these parameters. The temperature dependences of the muon hyperfine couplings were also studied and were found to be highly sensitive to the type of catalyst, and so to the nature of the adsorption site.
Anomeric conformations of six‐membered cyclic aminoxyl radicals with a β‐alkoxyl substituent
Authors: Zhang Yong‐Kang , Janzen Edward G. , Kotake Yashige
Published: May 2005

The addition reactions of CH3(CH2)3O·, (CH3)2CHCH2O·, (CH3)2CHCH2CH2O·, (CH3)3CO· and (CH3)2C(CN)O· radicals to a novel six‐membered cyclic nitrone, 6,6‐dimethyl‐3,4,5,6‐tetrahydropyridine N‐oxide (M2PyO), generate the corresponding 6‐alkoxyl‐2,2‐dimethylpiperidine‐1‐oxyl aminoxyl (nitroxide) spin adducts. In benzene solution at room temperature, the preferential conformation of these spin adducts appears to be the anomeric conformer with the alkoxyl group in the axial position according to EPR spectroscopic conformational analysis of these aminoxyls. The anomeric effect in these aminoxyls might be the combination of electrostatic and molecular orbital interactions.
EPR imaging in biological applications: Towards microtomography
Authors: Sotgiu A. , Placidi G. , Gualtieri G. , Tatone C. , Campanella C.
Published: May 2005

EPR imaging and microtomography promises to be a powerful tool for the EPR spectroscopist, but the expansion of this technique was hindered by the lack of commercial apparatus. A simple modification of an existing commercial system that can reach a resolution of the order of 75 μm with a gradient of 150 mT m−1 is described. This resolution can be increased by using larger field gradients. In many biological applications this resolution is significant. As an example, the distribution of a paramagnetic probe in an amphibious egg cell is presented that permits one to distinguish the nucleus of the cell. A summary of the mathematical techniques which enable one to account for the presence of a hyperfine structure in most EPR paramagnetic probes and to increase resolution is also presented.
Dynamic behaviour of a nitroxide biradical undergoing multiple internal motions: An ESR and 13C NMR relaxation study
Authors: Chachaty Claude , Gambarelli Serge , Rassat André
Published: May 2005

The ESR spectra of the bis(2,2,6,6‐tetramethyl‐4‐piperidinol‐1‐oxyl) adipate biradical at several temperatures in ethanol solution were simulated, taking into account all allowed conformers corresponding to the rotational isomerism model. The probabilities of these conformers, not accessible by ESR, were derived from 13C spin relaxation measurement on the diamagnetic reduced form of the biradical. The least‐squares fits of ESR spectra provided the temperature dependence of the rates of internal motions and of the tumbling correlation time of the biradical and also an estimate of the electron spin exchange parameters.
Luminescence in cubic boron nitride doped by rare‐earth impurity
Authors: Shishonok E. M. , Philipp A. R. , Shishonok N. A. , Anichenko N. G.
Published: May 2005

We report shortly the observation of visible cathodoluminescence (CL) from micropowders of Eu‐doped cubic boron nitride synthesized under high‐pressure/high‐temperature conditions and also annealed in a vacuum in the temperature range from 400 to 1100 °C. The multiplet of lines due to the intra‐ 4f transitions on the Eu3+ ion is detected in spectral region from 580 to 740 nm. The fact that the main line of the multiplet has the highest intensity, and the removed degeneracy of the 7F1 and 7F2 electronic levels represented by the second and third bands of the multiplet allow the conclusion that the red luminescence is due to the Eu2O3 inclusions in the monoclinic form (probably, as nano particles) incorporated into the cBN grains. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analytical solution for V‐groove quantum wire with an effective potential scheme
Authors: Sadeghi E. , Khordad R.
Published: May 2005

We present an analytical method for calculating the energy spectra of electron and hole in V‐groove quantum wire. The carrier ground states as well as the wave functions are calculated by an effective potential model together with a suitable coordinate transformation that allows the decoupling of the two‐dimensional wave function. The result clearly indicates the strong confinement of both electrons and holes. The calculated energy of carrier and wave function by this analytical method are in good agreement with the earlier numerical investigations. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhancement between layers in multiple‐layer thin‐film samples
Authors: Willis James E.
Published: May 2005

Secondary fluorescence effects are calculated and compared with the total fluorescence for multiple‐layer thin‐film samples of Fe, Ni and Fe, Ni, Cu, Cr. The ratio of secondary to total fluorescence for a given analyte is found to be greater in the system where the enhancer is in a layer which is closer to the surface. Secondary fluorescence effects are calculated for a Ni thin film on an Sn sample. Unusual acquisition conditions cause the intensity from the Ni thin film layer to exceed the intensity from a bulk sample of Ni.
Heterogeneity effects and the reliability of X‐ray fluorescence analytical results: Study on Al2O3 matrix with calcium, yttrium, gadolinium and thorium as probe elements
Authors: Agrawal R. M. , Kapoor S. K.
Published: May 2005

Synthetic standards obtained by dry mixing of the components in appropriate proportions, when used as calibration standards in XRF analysis can be a major source of error in the analytical results, owing to the differences in the degree of their homogeneity compared with that of the sample. In an earlier study U3O8 was used as the matrix and Ca, Y, Gd and Th in the low concentration range (0–1500 ppm) as probe impurity elements. The study has now been extended to the low‐Z matrix Al2O3 using the same impurity elements as probe elements and the same concentration range. This study also clearly illustrates the incompatibility of truely homogeneous standards with standards obtained by dry mixing and grinding and corroborates the results obtained in the earlier study. However, some of the general inferences drawn earlier required modification in order to explain the results for the two matrices. The effect of binding material, which is often required for briquetting the sample into pellet form and must be mixed with the sample by dry mixing, is discussed.
Quantitative elemental analysis of thick samples by XRF and PIXE
Authors: Gil F. B. , Barreira G. , Guerra M. F. , Alves L. C.
Published: May 2005

An absolute quantitative analytical method without external standards has been developed for thick sample analysis by XRF and PIXE and has been applied to bronze and brass alloys. Comparisons between the results obtained and the chemical results were made and the detection limits for the determined elements were evaluated. In an Appendix a rapid calculation of the efficiency of the Ge(Hp) detector is presented.
Method for the determination of the phase fractions in solid systems by x‐ray microanalysis
Authors: Stoyanchev R.
Published: May 2005

A method is proposed for the quantitative evaluation of area fractions of phases with different chemical compositions in solid systems, e.g. alloys, mixtures of solid solutions and phases with defined stoichiometry, ceramics and minerals. The method is based on the scanning of the surface of the sample by an electron beam and applying an energy‐dispersive x‐ray spectrometer. By using the net integral intensities of the characteristic x‐ray lines of the elements in the different phases, equations have been derived for the area fractions of an n‐phase system composed of m elements. Assuming that the phases are uniformly distributed within the sample, the practically important volume and weight fractions of the phases are expressed by the area fractions. A technique for the assessment of the elemental content in a complex sample using an electron probe is given, by using the phase fractions determined by the proposed method and the concentration data for the elements in the separate phases. The method has been tested experimentally for the determination of the area fractions in cases where the number of phases is less than or equal to the number of constituent elements.
Determination of the various phases of aluminium in steel by x‐ray fluorescence spectrometry
Authors: Klockenkämper R. , Koch K. H.
Published: May 2005

The total content of aluminium in steel can be determined from the Kα line in the x‐ray spectrum with a detection limit of 0.001%. However, aluminium is generally present in three phases, as metal, as nitride and as oxide; these different phases are of metallurgical significance and have to be distinguished. This is possible from their different kβ bands in the x‐ray spectrum, which were found at 1555.3 1553.9 and 1552.5 eV, respectively. The physical bandwidth of about x‐ray 7 eV, however, causes overlapping of the peaks, so that an unfolding procedure is needed. The defection limit of the different phases was determined to be 0.06% which, unfortunately, is above the region of interest for modern steel analysis. In addition, the analysis time of about 3 min is too long for use in process control, so that the classical methods for pahse determination cannot be replaced by x‐ray fluorescence analysis.
H-surface index formula
Authors: Jakob Ruben
Published: May 2005

We construct an additive index

\mathcal {I}

on the set of compact “parts” of the set

\mathcal {H}_{H}(\Gamma )

of “small” H-surfaces (

|H| < \frac{1}{2}

) that are spanned into a simple closed polygon

\Gamma \subset \mathbb{R}^{3}

with

N + 3

vertices (

N⩾1

) by a combination of Heinz' and Hildebrandt's examinations of H-surfaces and Dold's fixed point theory. We obtain that the index of

\mathcal {H}_{H}(\Gamma )

is always 1, independent of

H

and

Γ

. Moreover we compute that the Čech cohomology

\check H(\mathcal {P})

of a part

\mathcal {P}

that minimizes the H-surface functional

\mathcal {E}^{H}

locally is non-trivial at most in degrees

0,\dots,N−1

and there even finitely generated, which implies the finiteness of the number of connected components of

\mathcal {P}

in particular. Finally the index of such an “

\mathcal {E}^{H}

-minimizing” part reveals to coincide with its Čech–Euler characteristic, which yields a variant of the mountain-pass-lemma.
NF‐κB and NOS may play a role in human RPMI‐8402 cell apoptosis
Authors: Trubiani Oriana , Salvolini Eleonora , Vignini Arianna , D'Arcangelo Camillo , Di Primio Roberto , Mazzanti Laura
Published: May 2005

Apoptosis is a fundamental process that is required for the normal development and functioning of the immune system. It can be induced in different ways depending on cell type and acquired signal. Since the NF‐κB transcription factor complex is believed to be involved in nitric oxide‐induced apoptosis, the aim of this study was to investigate NF‐κB and nitric oxide synthase (NOS) activity during dimethyl sulphoxide (DMSO)‐dependent cell death of RPMI‐8402 human pre‐T cells. Our results show that NF‐κB activation is associated with a significant up‐regulation of NOS activity and induction of apoptosis. Furthermore, the inhibition and reversal of these effects by parthenolide treatment or DMSO removal indicate that these molecules are directly involved in the progression of cell death.
Impact of Symptom Prevalence and Symptom Burden on Quality of Life in Patients with Heart Failure
Authors: Zambroski Cheryl Hoyt , Moser Debra K. , Bhat Geetha , Ziegler Craig
Published: May 2005

Background: Heart failure is an escalating health problem around the world. Despite significant scientific advances, heart failure patients experience multiple physical and psychological symptoms that can impact the quality of life.

Aims: To determine the (1) symptom prevalence, severity, distress and symptom burden in patients with heart failure; (2) impact of age and gender on symptom prevalence, severity, distress and symptom burden; and (3) impact of symptom prevalence and symptom burden on health-related quality of life (HRQOL) in patients with heart failure.

Methods: A convenience sample of 53 heart failure patients participated in this descriptive, cross-sectional design. Symptoms and HRQOL were measured using the Memorial Symptom Assessment Scale—Heart Failure and the Minnesota Living with Heart Failure Questionnaire.

Results: Patients experienced a mean of 15.1 ± 8.0 symptoms. Shortness of breath and lack of energy were the most prevalent. Difficulty sleeping was the most burdensome symptom. Lower age, worse functional status, total symptom prevalence and total symptom burden predicted 67% of the variance in HRQOL.

Conclusion: Patients with heart failure experience a high level of symptoms and symptom burden. Nurses should target interventions to decrease frequency, severity, distress and overall symptom burden and improve HRQOL.
Attenuation of postoperative noradrenaline need by nitric oxide inhibition using L‐NMMA
Authors: Franco‐Cereceda Anders , Holm Peter , Bredin Fredrik , Adding Christoffer
Published: May 2005

In the present report we describe that NG‐monomethyl‐L‐arginine acetate, a non‐specific nitric oxide synthesis inhibitor, administered at 1 mg kg–1 h–1 to a patient with critical hypotension following mitral valve surgery combined with passive containment surgery, increased the urinary output and arterial blood pressure while the need for noradrenaline was rapidly attenuated. Again increasing the noradrenaline infusion in the presence of NG‐monomethyl‐L‐arginine acetate caused a dramatic increase of the blood pressure.
Interaction of the protein phosphatase 2A with the regulatory domain of the cystic fibrosis transmembrane conductance regulator channel
Authors: Vastiau Annick , Cao Lishuang , Jaspers Martine , Owsianik Grzegorz , Janssens Veerle , Cuppens Harry , Goris Jozef , Nilius Bernd , Cassiman Jean-Jacques
Published: May 2005

A direct interaction of the regulatory domain (R domain) of the cystic fibrosis transmembrane conductance regulator protein (CFTR) with PR65, a regulatory subunit of the protein phosphatase 2A (PP2A), was shown in yeast two hybrid, pull‐down and co‐immunoprecipitation experiments. The R domain could be dephosphorylated by PP2A in vitro. Overexpression of the interacting domain of PR65 in Caco‐2 cells, as well as treatment with okadaic acid, showed a prolonged deactivation of the chloride channel. Taken together our results show a direct and functional interaction between CFTR and PP2A.
Proteolytic cleavage of ALF into α‐ and β‐subunits that form homologous and heterologous complexes with somatic TFIIA and TRF2 in male germ cells
Authors: Catena Raffaella , Argentini Manuela , Martianov Igor , Parello Catherine , Brancorsini Stefano , Parvinen Martti , Sassone-Corsi Paolo , Davidson Irwin
Published: May 2005

Male germ cells specifically express paralogues of components of the general transcription apparatus including ALF a paralogue of TFIIAα/β. We show that endogenous ALF is proteolytically cleaved to give α‐ and β‐subunits and we map the proteolytic cleavage site by mass spectrometry. Immunoprecipitations show that ALFα‐ and β‐subunits form a series of homologous and heterologous complexes with somatic TFIIA which is coexpressed in male germ cells. In addition, we show that ALF is coexpressed in late pachytene spermatocytes and in haploid round spermatids with transcription factor TRF2, and that these proteins form stable complexes in testis extracts. Our observations highlight how cleavage of ALF and coexpression with TFIIA and TRF2 increases the combinatorial possibilities for gene regulation at different developmental stages of spermatogenesis.
Controlling postpartum hemorrhage after home births in Tanzania
Authors: Prata N. , Mbaruku G. , Campbell M. , Potts M. , Vahidnia F.
Published: May 2005

Objectives: Determine safety of household management of postpartum hemorrhage (PPH) with 1000 μg of rectal misoprostol, and assess possible reduction in referrals and the need for additional interventions. Methods: Traditional birth attendants (TBAs) in Kigoma, Tanzania were trained to recognize PPH (500 ml of blood loss). Blood loss measurement was standardized by using a local garment, the “kanga”. TBAs in the intervention area gave 1000 μg of misoprostol rectally when PPH occurred. Those in the non‐intervention area referred the women to the nearest facility. Results: 454 women in the intervention and 395 in the non‐intervention areas were eligible. 111 in the intervention area and 73 in the non‐intervention had PPH. Fewer than 2% of the PPH women in the intervention area were referred, compared with 19% in the non‐intervention. Conclusion: Misoprostol is a low cost, easy to use technology that can control PPH even without a medically trained attendant.
Maternal and perinatal outcome of pregnancies complicated by cardiac disease
Authors: Abdel‐Hady E.‐S. , El‐Shamy M. , El‐Rifai A.‐A. , Goda H. , Abdel‐Samad A. , Moussa S.
Published: May 2005

Objective: The aim of this study was to assess the maternal and perinatal outcome of pregnancies complicated by cardiac disease in a tertiary care center in Egypt. Methods: During a 1‐year period, a total of 86 pregnant women with cardiac disease were admitted. Maternal and perinatal morbidity and mortality were calculated and compared with a control group. Results: Seventy‐seven (89.5%) patients were due to rheumatic affection, and 60 patients were classified as NYHA classes I–II. There was one case of maternal mortality (1.16%), and 10 other cases developed life‐threatening complications. Two perinatal mortalities (2.32%) occurred in this series. Birth weight of babies born to mothers with functional classes III and IV were significantly lower than those of functional classes I–II and control group. Conclusion: Rheumatic heart disease with pregnancy is still predominant in Egypt. Maternal and perinatal morbidity and mortality are strongly correlated to maternal cardiac functional classification.
Hypothalamic‐pituitary‐gonadal function in adolescent females with beta‐thalassemia major
Authors: Al‐Rimawi H.S. , Jallad M.F. , Amarin Z.O. , Obeidat B.R.
Published: May 2005

Objective: To evaluate the function of the hypothalamic‐pituitary‐gonadal axis in adolescent female patients with beta‐thalassemia major. Materials and methods: A prospective study of the function of the hypothalamic‐pituitary‐gonadal axis function of 31 beta‐thalassemia major females aged between 13 and 22 years and in 12 control females aged between 12 and 22 years. All were treated at Princess Rahma Teaching Hospital, Irbid, Northern Jordan between April 2001 and April 2003. Results: Of the 31 beta‐thalassemia major females, 13 (41.9%) had delayed puberty. Hypothalamic‐pituitary‐ovarian axis dysfunction was found in 15 patients (48.4%). Twelve patients (38.7%) had hypogonadotropic hypogonadism and 5 (16.1%) had ovarian failure. High levels of serum ferritin were significantly higher in patients with delayed puberty. Conclusion: Pituitary and ovarian dysfunction are common problems in beta‐thalassemia major patients. The main possible cause is iron overload. This stresses the need for intensive and regular use of chelation therapy to prevent damage to the hypothalamic‐pituitary‐ovarian axis.
Titres of alloantibodies against A and B blood types in non-pedigree domestic cats in Turkey: Assessing the transfusion reaction risk
Authors: Gurkan Mehmet , Arikan Şevket , Ozaytekin Ebru , Dodurka Tamer
Published: May 2005

The severity of a transfusion reaction depends on alloantibody titres within the recipients' blood. Determination of an agglutination titre of naturally occurring alloantibody may help to assess the risk of transfusion reactions following an unmatched transfusion in a cat population. In this group of 312 cats 227 had blood type A, 78 had blood type B, and seven had type AB blood. All type B cats tested showed gross evidence of agglutinating anti-A antibody with plasma titres ranging from 2 to 256. Among the 227 type A domestic cats tested for plasma anti-B alloantibody titres, 70% had gross agglutination with titres ranging from 2 to 16, while 17.6% had microscopic agglutination. The remaining 12.4% of the type A cats were negative for both gross and microscopic agglutination. Based on agglutinating titres, the relative risk of a transfusion reaction when type A or AB blood was given to a type B cat was 6.4% with acute severe reaction, acute mild reactions in 85.9% and premature red cell destruction in 7.7%. On the other hand, transfusion of type AB blood or type B blood to type A cats carries a potential risk of acute mild transfusion reaction in 4.4% and premature red cell destruction in 83.3%. Transfusion of type A or B blood to type AB cats results in no apparent clinical transfusion reactions.
Primary hyperoxaluria (l-glyceric aciduria) in a cat
Authors: De Lorenzi Davide , Bernardini Marco , Pumarola Marti
Published: May 2005

A 7-month-old, male European cat was examined because of weakness and inappetence. The cat was dehydrated, polypnoeic and severely weak. Severe, generalised muscle atrophy was present. Spinal reflexes were all decreased to absent. Blood analysis and urinalysis showed several abnormalities, including intermittent hyperoxaluria. The l-gliceric acid concentration was remarkably increased. Electrodiagnostic tests of the peripheral nervous system were abnormal. At necropsy, generalised muscle atrophy was observed. Microscopically, both kidneys showed intraluminal birefringent oxalate crystals. Motor neuron degeneration and accumulation of neurofilaments were observed in the axons of the spinal motor neurons.
Flexibility and technology choice in gas fired power plant investments
Authors: Näsäkkälä Erkka , Fleten Stein‐Erik
Published: May 2005

The value of a gas fired power depends on the spark spread, defined as the difference between the price of electricity and the cost of gas used for the generation of electricity. We model the spark spread using a two‐factor model, allowing mean‐reversion in short‐term variations and uncertainty in the equilibrium price to which prices revert. We analyze two types of gas plants: peak and base load plants. A peak load plant generates electricity when spark spread exceeds emission costs, whereas a base load plant generates electricity at all levels of spark spread. A base load plant can be upgraded to a peak load plant. First, we find the upgrading threshold for a base load plant. The upgrading threshold gives the optimal type of gas plant as a function of spark spread. Second, we calculate building threshold for the investment costs. When the investment costs are below the threshold it is optimal to build the plant with the previously solved optimal technology. In the numerical example, we illustrate how our model can be used when investments in gas fired power plants are considered.
Magnetostratigraphic dating of the Donggutuo and Maliang Paleolithic sites in the Nihewan Basin, North China
Authors: Wang Hongqiang , Deng Chenglong , Zhu Rixiang , Wei Qi , Hou Yamei , Boëda Eric
Published: May 2005

A detailed magnetostratigraphic investigation, coupled with rock-magnetic studies, was carried out on a lacustrine sequence in the eastern Nihewan Basin, Northern China, which contains the Donggutuo and Maliang Paleolithic sites. Magnetite and hematite were identified as the main carriers for the characteristic remanent magnetizations. Magnetostratigraphic results show that the lacustrine sequence recorded the late Matuyama and Brunhes chrons. Furthermore, the Maliang artifact layer occurs just below the Brunhes/Matuyama boundary, and the Donggutuo artifact layer is just below the Jaramillo onset. Therefore, the age of the Maliang and Donggutuo artifact layers can be definitely estimated to be about 0.78 myr and 1.1 myr, respectively. These two paleomagnetic ages, coupled with previously obtained paleomagnetic data of the Majuangou, Xiaochangliang, Banshan, Lantian, and Xihoudu Paleolithic sites, suggest an expansion and lengthy flourishing of human groups from northern to north-central China during the entire Early Pleistocene.
The chromatic scales of the Deuteros modes in theory and practice
Authors: MAKRIS EUSTATHIOS
Published: May 2005

The idea that the Deuteros modes (second authentic and second plagal) of Greek liturgical chant already had a chromatic character before the end of the Byzantine era has gained wide acceptance in the last decades. Trying to go one step further and reconstruct the scales of these modes, the present article attempts a new interpretation of certain crucial passages in late Byzantine treatises, which can provide important clues, if interpreted in connection with the description of the modes in modern Greek music theory and their actual characteristics in the written and oral tradition. The resulting structures can serve as a basis for future transcriptions of chants, at least for the late and post-Byzantine repertory.
Tonal structure and the melodic role of chromatic inflections in the music of Machaut
Authors: BAIN JENNIFER
Published: May 2005

The interpretation of chromatic content in fourteenth-century music has been widely debated. While most studies have focused on contrapuntal necessity, this study advocates an approach that begins from the perspective of melody. Using the ballades, virelais and rondeaux of Guillaume de Machaut as a central repertory, it proposes that not only are chromatic inflections in Machaut's monophonic songs derived melodically, but that many chromatic inflections in Machaut's polyphonic songs also arise from melodic rather than contrapuntal requirements. Because of their implied semitone motion – arguably crucial to tonal organization – they can have an impact on the definition of tonal structure by privileging the individual pitches they decorate, particularly but not exclusively in cadential melodic formulas or progressions.
Recent Recordings of Plainchant
Authors: WEBER JEROME F.
Published: May 2005

An effort to catch up on missing discs to be included in the Second Edition of my discography has resulted in an unusually long list this year. ‘Christus Rex’ (1997, no. 2) proved to be the first disc in a series featuring Hervé Lamy, a soloist with the Chœur Grégorien de Paris. It has been followed by ‘Spiritus Domini’ (no. 1 in the list below) and ‘Pater Noster’ (no. 3) to form a Trinitarian programme of chants related to each of the Three Divine Persons. In a similar vein, ‘Le Livre d’Heures de Charlemagne' (no. 2) offers groups of chants that focus on the Carolingian chant reform and other aspects of the king's life. Most of the chants belong to a soloist, Lamy's superb professional tenor a perfect vehicle for interpretations that are faithful to current standards yet inspired by a sensitive interpreter. Credo IV, leading off no. 1, is not a good choice for a solo, but it is sung with great panache. The Ambrosian Gloria and the Te Deum on the same disc are better alternating with the men's schola. For the rest, the Exsultet (on no. 3), lamentations, lessons from Office and Mass, and offertories with verses are ideal selections. An original touch also in no. 3 is a passage of St Matthew's gospel that leads into the communion chant Pater si non potest. The Laudes Regiae, heard on the earlier disc already, are sung again for Charlemagne, Pope Leo and Archbishop Hincmar. These are magnificent examples of recorded chant.
A 3‐year field measurement of methane and nitrous oxide emissions from rice paddies in China: Effects of water regime, crop residue, and fertilizer application
Authors: Zou Jianwen , Huang Yao , Jiang Jingyan , Zheng Xunhua , Sass Ronald L.
Published: May 2005

A 3‐year field experiment was conducted to simultaneously measure methane (CH4) and nitrous oxide (N2O) emissions from rice paddies under various agricultural managements including water regime, crop residue incorporation, and synthetic fertilizer application. In contrast with continuous flooding, midseason drainage incurred a drop in CH4 fluxes while triggering substantial N2O emission. Moreover, N2O emissions after midseason drainage depended strongly on whether or not fields were waterlogged due to intermittent irrigation. Urea application tended to reduce CH4 emissions but significantly increased N2O emissions. Under a water regime of flooding‐midseason drainage‐reflooding‐moist intermittent irrigation but without water logging (F‐D‐F‐M), both wheat straw and rapeseed cake incorporation increased CH4 emissions by 252%, and rapeseed cake increased N2O by 17% while wheat straw reduced N2O by 19% compared to controls. Seasonal average fluxes of CH4 ranged from 25.4 mg m−2 d−1 when no additional residue was applied under the water regime of flooding‐midseason drainage‐reflooding to 116.9 mg m−2 d−1 when wheat straw was applied at 2.25 t ha−1 under continuous irrigation flooding. Seasonal average fluxes of N2O varied between 0.03 mg N2O‐N m−2 d−1 under continuous flooding and 5.23 mg N2O‐N m−2 d−1 under the water regime of F‐D‐F‐M. Both crop residue‐induced CH4, ranging from 9 to 15% of the incorporated residue C, and N2O, ranging from 0.01 to 1.78% of the applied N, were dependent on water regime in rice paddies. Estimations of net global warming potentials (GWPs) indicate that water management by flooding with midseason drainage and frequent water logging without the use of organic amendments is an effective option for mitigating the combined climatic impacts from CH4 and N2O in paddy rice production.
Fluid flow and seismicity pattern: Evidence from the 1997 Umbria‐Marche (central Italy) seismic sequence
Authors: Antonioli Andrea , Piccinini Davide , Chiaraluce Lauro , Cocco Massimo
Published: May 2005

We model the spatial and temporal evolution of seismicity during the 1997 Umbria‐Marche seismic sequence in terms of subsequent failures promoted by fluid flow. The diffusion process of pore‐pressure relaxation is represented as a pressure perturbation generated by coseismic stress changes and propagating through a fluid saturated medium. The values of isotropic diffusivity range between 22 and 90 m2/s. The calculated value of anisotropic diffusivity (Daniso= 250 m2/s) is largest along the average strike (N140°) direction of activated faults. Our results suggest that the observed spatio‐temporal migration of seismicity is consistent with fluid flow.
Satellite‐derived vertical dependence of tropical tropospheric temperature trends
Authors: Fu Qiang , Johanson Celeste M.
Published: May 2005

Tropical atmospheric temperatures in different tropospheric layers are retrieved using satellite‐borne Microwave Sounding Unit (MSU) observations. We find that tropospheric temperature trends in the tropics are greater than the surface warming and increase with height. Our analysis indicates that the near‐zero trend from Spencer and Christy's MSU channel‐2 angular scanning retrieval for the tropical low‐middle troposphere (T2LT) is inconsistent with tropical tropospheric warming derived from their MSU T2 and T4 data. We show that the T2LT trend bias can be largely attributed to the periods when the satellites had large local equator crossing time drifts that cause large changes in calibration target temperatures and large diurnal drifts.
Interannual variations of the diurnal tide in the mesosphere generated by the quasi‐biennial oscillation
Authors: Mayr Hans G. , Mengel John G.
Published: May 2005

We report results from a study with the numerical spectral model (NSM), which produces significant interannual variations in the diurnal tide. Applying Hines's Doppler spread parameterization, small‐scale gravity waves (GWs) drive the quasi‐biennial oscillation (QBO) and semiannual oscillation. With a GW source that peaks at the equator and is taken to be isotropic and independent of season, the NSM generates a QBO with variable periods around 26 months and zonal wind amplitudes close to 25 m s−1 at 30 km. As reported earlier, the NSM reproduces the observed equinoctial maxima in the diurnal tide at altitudes around 95 km. In the present paper it is shown that the QBO also modulates the tide such that the seasonal amplitude maxima can vary from one year to another by as much as 30%. To shed light on the underlying mechanisms, the relative importance of the linearized advection terms is discussed, which involve the meridional and vertical winds of the diurnal tide. These interactions generate pronounced QBO modulations of the tide at altitudes below 50 km. In the mesosphere between 50 and 80 km the signature is not well defined because of interference from the seasonal variations. At altitudes above 80 km, however, the QBO‐related interannual variations of the tide are again relatively large, but they are generated primarily by GW momentum deposition. Since the period of the QBO is variable and its phase is relative to the seasonal cycle changes, the magnitude of the QBO modulation of the tide in the upper mesosphere varies considerably as our long‐term model simulation shows. This intermittency must be attributed to nonlinear interactions, and GW drag (momentum deposition) is discussed as a potential candidate.
Influence of isentropic transport on seasonal ozone variations in the lower stratosphere and subtropical upper troposphere
Authors: Jing P. , Cunnold D. M. , Yang E.‐S. , Wang H.‐J.
Published: May 2005

The isentropic cross‐tropopause ozone transport has been estimated in both hemispheres in 1999 based on the potential vorticity mapping of Stratospheric Aerosol and Gas Experiment II ozone measurements and contour advection calculations using the NASA Goddard Space Flight Center Global and Modeling Assimilation Office analysis. The estimated net isentropic stratosphere‐to‐troposphere ozone flux is ∼118 ± 61 × 109 kg yr−1 globally within the layer between 330 and 370 K in 1999; 60% of it is found in the Northern Hemisphere, and 40% is found in the Southern Hemisphere. The monthly average ozone fluxes are strongest in summer and weakest in winter in both hemispheres. The seasonal variations of ozone in the lower stratosphere (LS) and upper troposphere (UT) have been analyzed using ozonesonde observations from ozonesonde stations in the extratropics and subtropics, respectively. It is shown that observed ozone levels increase in the UT over subtropical ozonesonde stations and decrease in the LS over extratropical stations in late spring/early summer and that the ozone increases in the summertime subtropical UT are unlikely to be explained by photochemical ozone production and diabatic transport alone. We conclude that isentropic transport is a significant contributor to ozone levels in the subtropical upper troposphere, especially in summer.
The evolution of precipitable water associated with the Asian and Australian monsoons as revealed from MODIS/SSMI, ECMWF and NCEP reanalysis data sets
Authors: Li Hui , Chen Baode
Published: May 2005

By using MODIS/SSMI merged water vapor data, the evolution of total precipitable water (TPW) associated with the Asian and Australian monsoons has been studied. In addition to the satellite data, the monthly means of TPW data from the National Center for Environmental Prediction (NCEP) Reanalysis II and the European Centre for Medium‐Range Weather Forecasts (ECMWF) 40‐year Reanalysis (ERA‐40) are used to compare with the merged TPW data. The large TPW is associated with the onsets of the Asian and Australian monsoons and shows a pronounced seasonal variability. Within northern Australia the annual mean TPW from the NCEP and SSMI/MODIS data sets show a decreasing trend over the last five years and the ERA‐40 over the 2.5 years but no obvious trend can be found within southern Asia, indicating that the atmosphere tends to become “drier” over the Australian monsoon region. The result from available ERA‐40 data set shows a quite similar feature with that of the merged TPW. However the NCEP TPW, which may be mostly influenced by the forecast model, particularly, by the performance of the physical parameterizations, has underestimated the TPW and has a rather unsystematic evolution in terms of seasonal migration.
Have olivine, will gas: Serpentinization and the abiogenic production of methane on Mars
Authors: Oze Christopher , Sharma Mukul
Published: May 2005

Spatial variability of methane (CH4) on Mars suggests the presence of localized subsurface sources. Here, we show that olivine hydration in the Martian regolith and crust may be a major CH4 source, which contributed significantly to the warming of early Mars. Methane production is kinetically and thermodynamically favored during low‐T aqueous alteration of olivine‐rich rocks. Sustained release of CH4 on present‐day Mars may come through the breakdown of ancient CH4 hydrates and from springs driven by geothermal heat.
Multiinjection Approach for D2 Receptor Binding Quantification in Living Rats using [11C]Raclopride and the β-Microprobe: Crossvalidation with in Vitro Binding Data
Authors: Mauger Gweltas , Saba Wadad , Hantraye Philippe , Dolle Frédéric , Coulon Christine , Bramoullé Yann , Chalon Sylvie , Greégoire Marie-Claude
Published: May 2005

The purpose of this study was to quantify D2 receptors density and affinity in living rats using [11C]raclopride and to validate the multiinjection modelling approach. To this aim, we used an intracerebral β+-sensitive probe as a highly sensitive system to quantify the radioligand activity using a single three-injection experimental paradigm. The study was divided into three main parts: (i) [11C]raclopride catabolism evaluation without and with cimetidine pretreatment (cytochrome P450 inhibitor); (ii) quantification of kinetics parameters in the striatum, enthorinal cortex, and cerebellum of living rats using a three-compartment model with an arterial input function; (iii) correlation study of in vivo and in vitro binding density and affinity values in the same striatal tissues. (i) raclopride catabolism was very reproducible between individuals; cimetidine pre-treatment resulted in a 30% reduction of raclopride metabolites. (ii) D2 striatal B'max and Kd Vr estimates obtained by compartmental modelling were 19.87 ± 6.45 and 6.2 ± 3.3 nmol/L, respectively. Cerebellum is the best candidate as a reference region with no specific binding detectable in vivo. (iii) When comparing density ( Bmax/ B'max) and affinity ( Kd/ Kd Vr) values in vivo and in vitro for each striatum, a high strict correlation was found ( r2 = 0.90 and 0.72, for density and affinity, respectively). These results validate the multi-injection modelling approach coupled to β-microprobe acquisitions as a mean to provide accurate and separate estimates of dopamine D2-receptor density and affinity, in the living rodent striatum.
Glycolysis versus TCA Cycle in the Primate Brain as Measured by Combining 18F-FDG PET and 13C-NMR
Authors: Boumezbeur Fawzi , Besret Laurent , Valette Julien , Gregoire Marie-Claude , Delzescaux Thierry , Maroy Renaud , Vaufrey Françoise , Gervais Philippe , Hantraye Philippe , Bloch Gilles , Lebon Vincent
Published: May 2005

The glycolytic flux (cerebral metabolic rate of glucose CMRglc) and the TCA cycle flux ( VTCA) were measured in the same monkeys by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and 13C NMR spectroscopy, respectively. Registration of nuclear magnetic resonance (NMR) and PET data were used for comparison of CMRglc and VTCA in the exact same area of the brain. Both fluxes were in good agreement with literature values (CMR glc 0.23 ± 0.03 μmol/g min, VTCA = 0.53 ± 0.13 μmol/gmin). The resulting [ CMRglc/VTCA] ratio was 0.46 ± 0.12 ( n = 5, mean ± s.d.), not significantly different from the 0.5 expected when glucose is the sole fuel that is completely oxidized. Our results provide a cross-validation of both techniques. Comparison of CMRglc with VTCA is in agreement with a metabolic coupling between the TCA cycle and glycolysis under normal physiologic conditions.
Heme Regulation in Traumatic Brain Injury: Relevance to the Adult and Developing Brain
Authors: Chang Edward F , Claus Catherine P , Vreman Hendrik J , Wong Ronald J , Noble-Haeusslein Linda J
Published: May 2005

Intracranial bleeding is one of the most prominent aspects in the clinical diagnosis and prognosis of traumatic brain injury (TBI). Substantial amounts of blood products, such as heme, are released because of traumatic subarachnoid hemorrhages, intraparenchymal contusions, and hematomas. Despite this, surprisingly few studies have directly addressed the role of blood products, in particular heme, in the setting of TBI. Heme is degraded by heme oxygenase (HO) into three highly bioactive products: iron, bilirubin, and carbon monoxide. The HO isozymes, in particular HO-1 and HO-2, exhibit significantly different expression patterns and appear to have specific roles after injury. Developmentally, differences between the adult and immature brain have implications for endogenous protection from oxidative stress. The aim of this paper is to review recent advances in the understanding of heme regulation and metabolism after brain injury and its specific relevance to the developing brain. These findings suggest novel clinical therapeutic options for further translational study.
Wolter-like high resolution x-ray imaging microscope for Rayleigh Taylor instabilities studies
Authors: Troussel Ph. , Meyer B. , Reverdin R. , Angelier B. , Lidove G. , Salvatore P. , Richard A.
Published: May 2005

In the context of the inertial confinement fusion, experiments have been carried out on the Phebus laser facility to study the Rayleigh–Taylor instabilities (RTIs) at the ablation front. Premodulated brominated plastic targets (25μm thick) with a modulation wavelength between 12 and 50μm were accelerated with a temporally shaped soft x-ray pulse emitted from a hohlraum with a maximum radiation temperature of about 115eV. The RTI growth was measured by face-on radiography using a microscope coupled with an x-ray streak camera, which has spatial and temporal resolutions of about 5μm and 50ps, respectively. The acceleration was derived from side-on velocity measurements. The microscope we have developed is a Wolter-like microscope which consists of two toroïdal mirrors. We will present the experimental and theoretical potentialities of this microscope: characterization with an x-ray generator and plasma laser x-ray source (Phebus facility) for two-dimensional (2D) and 1D time-resolved imaging studies. Spatial resolution of about 4μm was achieved in the 1–5keV range. The Wolter-like constitutes an interesting device for laser plasma diagnostics and will be very useful in the Laser Mégajoules experiments conducted with more powerful lasers.
Limits of linear plasma wakefield theory for electron or positron beams
Authors: Lu W. , Huang C. , Zhou M. M. , Mori W. B. , Katsouleas T.
Published: May 2005

The validity and usefulness of linear wakefield theory for electron and positron bunches is investigated. Starting from the well-known Green’s function for a cold-fluid plasma, engineering formulas for the maximum accelerating field for azimuthally symmetric bi-Gaussian beams of the form nb=nbe−r2∕2σr2e−z2∕2σz2 are derived. It is also found that for fixed beam parameters the optimum wake is obtained for kpσz=21∕2, for kpσr⩽1. The validity and usefulness of linear-fluid theory is studied using fully nonlinear particle-in-cell simulations. It is found that linear theory can be useful beyond the nominal range of validity for narrow bunches. The limits of usefulness differ significantly between electron and positron bunches. For electron bunches, scaling laws are found for three limits for optimal plasma density (kpσz=21∕2), characterized by the normalized spot size kpσr and the normalized charge per unit length of the beam, Λ≡(nb∕np)kp2σr2. These are ε≡eE∕mcωp=1.3(nb∕np) for kpσr>1 and nb∕np<1, ε=1.3Λln(1∕kpσr), for (Λ∕10)1∕2<kpσr<1 and Λ<1, and ε=1.3Λln([10∕Λ]1∕2), for kpσr<(Λ∕10)1∕2 and Λ<1. Linear theory breaks down for nb∕np≅10. On the other hand, for positron drivers linear-fluid theory breaks down for nb∕np⩾1 independent of spot size.
Relativistic effective valence shell Hamiltonian method: Excitation and ionization energies of heavy metal atoms
Authors: Chaudhuri Rajat K. , Freed Karl F.
Published: May 2005

The relativistic effective valence shell Hamiltonian Hv method (through second order) is applied to the computation of the low lying excited and ion states of closed shell heavy metal atoms/ions. The resulting excitation and ionization energies are in favorable agreement with experimental data and with other theoretical calculations. The nuclear magnetic hyperfine constants A and lifetimes τ of excited states are evaluated and they are also in accord with experiment. Some of the calculated quantities have not previously been computed.