bluuebunny/crossref_metadata_2025 huggingface dataset:
Origin of the twofold and fourfold symmetric anisotropic magnetoresistance in epitaxial Fe3O4 films
Authors: Li P. , Jin C. , Jiang E. Y. , Bai H. L.
Published: November 2010

The angular dependence of anisotropic magnetoresistance (AMR) in epitaxial Fe3O4 films on several kinds of substrates has been investigated to explore the nature of AMR. All the measurements show that the dependence of AMR on the angle between current and magnetic field is the superimposition of sinusoidal twofold and fourfold symmetric AMR. The AMR in epitaxial Fe3O4 films is controlled by magnetic anisotropy and antiphase boundaries (APBs). The twofold and fourfold symmetric AMR originate from the scattering far away from the APBs and that near the APBs, respectively, which is consistent with the physical picture of magnetoresistance in epitaxial Fe3O4 films. The magnetic anisotropy, such as the uniaxial anisotropy induced by the step terraces and shape geometry, is closely related to the twofold symmetric AMR. The fourfold symmetric AMR is based on magnetocrystalline anisotropy and probably not correlated with the charge order in magnetite, which was verified by the fourfold symmetric AMR in octahedral-site doped epitaxial Ni0.3Fe2.7O4 films.
Structure, dielectric, and magnetic properties of Sr2TiMnO6 ceramics
Authors: Meher K. R. S. Preethi , Savinov M. , Kamba S. , Goian V. , Varma K. B. R.
Published: November 2010

Sr 2 TiMnO 6 , a double perovskite associated with high degree of B-site cation disorder was investigated in detail for its structural, magnetic, and dielectric properties. Though x-ray powder diffraction analysis confirms its cubic structure, first order Raman scattering and infrared reflectivity spectra indicate a breaking of the local cubic symmetry. The magnetization study reveals an anomaly at 14 K owing to a ferrimagnetic/canted antiferromagneticlike ordering arising from local Mn–O–Mn clusters. Saturated M-H hysteresis loops obtained at 5 K also reflect the weak ferromagnetic exchange interactions present in the system and an approximate estimation of Mn3+/Mn4+ was done using the magnetization data for the samples sintered at different temperatures. The conductivity and dielectric behavior of this system has been investigated in a broad temperature range of 10 to 300 K. Intrinsic permittivity was obtained only below 100 K whereas giant permittivity due to conductivity and Maxwell–Wagner polarization was observed at higher temperatures. X-ray photoemission studies further confirmed the presence of mixed oxidation states of Mn and the valence band spectra analysis was carried out in detail.
Imaging visible light with Medipix2
Authors: Mac Raighne Aaron , Brownlee Colin , Gebert Ulrike , Maneuski Dzmitry , Milnes James , O’Shea Val , Rügheimer Tilman K.
Published: November 2010

A need exists for high-speed single-photon counting optical imaging detectors. Single-photon counting high-speed detection of x rays is possible by using Medipix2 with pixelated silicon photodiodes. In this article, we report on a device that exploits the Medipix2 chip for optical imaging. The fabricated device is capable of imaging at >3000 frames/s over a 256×256 pixel matrix. The imaging performance of the detector device via the modulation transfer function is measured, and the presence of ion feedback and its degradation of the imaging properties are discussed.
Application of second-order Møller–Plesset perturbation theory with resolution-of-identity approximation to periodic systems
Authors: Katouda Michio , Nagase Shigeru
Published: November 2010

Efficient periodic boundary condition (PBC) calculations by the second-order Møller–Plesset perturbation (MP2) method based on crystal orbital formalism are developed by introducing the resolution-of-identity (RI) approximation of four-center two-electron repulsion integrals (ERIs). The formulation and implementation of the PBC RI-MP2 method are presented. In this method, the mixed auxiliary basis functions of the combination of Poisson and Gaussian type functions are used to circumvent the slow convergence of the lattice sum of the long-range ERIs. Test calculations of one-dimensional periodic trans-polyacetylene show that the PBC RI-MP2 method greatly reduces the computational times as well as memory and disk sizes, without the loss of accuracy, compared to the conventional PBC MP2 method.
Anomalies in electron spin resonance spectra of Ge1−xMnxTe diluted magnetic semiconductors
Authors: Zvereva E. A. , Savelieva O. A. , Primenko A. E. , Ibragimov S. A. , Slyn’ko E. I. , Slyn’ko V. E.
Published: November 2010

We report on magnetic properties and X-band electron spin resonance (ESR) study (80–430 K) of diluted magnetic semiconductors Ge1−xMnxTe (x=0.07–0.44) revealing ferromagnetism with the Curie temperature achieving 90 K. Effective magnetic moment peff per Mn2+ ion estimated from the Curie constant in the range 0.15≤x≤0.26 increases from 2.27 to 2.95 μB. The temperature evolution of ESR spectra was found to have a complicated character. We observed the presence of two distinct absorption lines of Dysonian type, associated with two resonance centers in these diluted magnetic semiconductors. Possible origin of these two lines has been analyzed and clustering effect was proposed to be most likely responsible for anomalous behavior. Anomalies in temperature dependencies of the linewidths and g-factors were observed at temperatures lower than 160 K. We connect these anomalies with magnetic fluctuations in the vicinity of transition to ferromagnetic phases. The anomalous broadening of the linewidth in paramagnetic region occurs with decreasing of the temperature similarly to ESR behavior of related A M2nB6 diluted magnetic semiconductors. This broadening is satisfactorily described in the framework of modified Huber’s theory. At the same time, the g-factor is essentially independent on both temperature and alloy composition. Average values of effective g-factor for two resolved spectral components at room temperature were found to be g1=2.02–2.07 and g2≈1.99.
A ground state morphed intermolecular potential for the hydrogen bonded and van der Waals isomers in OC:HI and a prediction of an anomalous deuterium isotope effect
Authors: Rivera-Rivera Luis A. , Wang Zhongcheng , McElmurry Blake A. , Willaert Fabrice F. , Lucchese Robert R. , Bevan John W. , Suenram Richard D. , Lovas Frank J.
Published: November 2010

An extended analysis of the noncovalent interaction OC:HI is reported using microwave and infrared supersonic jet spectroscopic techniques. All available spectroscopic data then provide the basis for generating an accurately determined vibrationally complete semiempirical intermolecular potential function using a four-dimensional potential coordinate morphing methodology. These results are consistent with the existence of four bound isomers: OC–HI, OC–IH, CO–HI, and CO–IH. Analysis also leads to unequivocal characterization of the common isotopic ground state as having the OC–HI structure and with the first excited state having the OC–IH structure with an energy of 3.4683(80) cm−1 above the ground state. The potential is consistent with the following barriers between the pairs of isomers: 382(4) cm−1 (OC–IH/OC–HI), 294(5) cm−1 (CO–IH/CO–HI), 324(3) cm−1 (OC–IH/CO–IH), and 301(2) cm−1 (OC–HI/CO–HI) defined with respect to each lower minimum. The potential is also determined to have a linear OC–IH van der Waals global equilibrium minimum structure having Re=4.180(11) Å, θ1=0.00(1)°, and θ2=0.00(1)°. This is differentiated from its OC–HI ground state hydrogen bound structure having R0=4.895(1) Å, θ¯1=20.48(1)°, and θ¯2=155.213(1)° where the distances are defined between the centers of mass of the monomers and θ¯1 and θ¯2 as cos−1[⟨cos2 θi⟩1/2] for i=1 and 2. A fundamentally new molecular phenomenon - ground state isotopic isomerization is proposed based on the generated semiempirical potential. The protonated ground state hydrogen-bonded OC–HI structure is predicted to be converted on deuteration to the corresponding ground state van der Waals OC–ID isomeric structure. This results in a large anomalous isotope effect in which the R0 center of mass distance between monomeric components changes from 4.895(1) to 4.286(1) Å. Such a proposed isotopic effect is demonstrated to be a consequence of differential zero point energy factors resulting from the shallower nature of hydrogen bonding at a local potential minimum (greater quartic character of the potential) relative to the corresponding van der Waals global minimum. Further consequences of this anomalous deuterium isotope effect are also discussed.
Radio-frequency characteristics of graphene oxide
Authors: Kim Whan Kyun , Jung Young Mo , Cho Joon Hyong , Kang Ji Yoong , Oh Ju Yeong , Kang Hosung , Lee Hee-Jo , Kim Jae Hun , Lee Seok , Shin H. J. , Choi J. Y. , Lee S. Y. , Kim Y. C. , Han I. T. , Kim J. M. , Yook Jong-Gwan , Baik Seunghyun , Jun Seong Chan
Published: November 2010

We confirm graphene oxide, a two-dimensional carbon structure at the nanoscale level can be a strong candidate for high-efficient interconnector in radio-frequency range. In this paper, we investigate high frequency characteristics of graphene oxide in range of 0.5–40 GHz. Radio-frequency transmission properties were extracted as S-parameters to determine the intrinsic ac transmission of graphene sheets, such as the impedance variation dependence on frequency. The impedance and resistance of graphene sheets drastically decrease as frequency increases. This result confirms graphene oxide has high potential for transmitting signals at gigahertz ranges.
Two-dimensional particle-in-cell Monte Carlo simulation of a miniature inductively coupled plasma source
Authors: Takao Yoshinori , Kusaba Naoki , Eriguchi Koji , Ono Kouichi
Published: November 2010

Two-dimensional axisymmetric particle-in-cell simulations with Monte Carlo collision calculations (PIC-MCC) have been conducted to investigate argon microplasma characteristics of a miniature inductively coupled plasma source with a 5-mm-diameter planar coil, where the radius and length are 5 mm and 6 mm, respectively. Coupling the rf-electromagnetic fields to the plasma is carried out based on a collisional model and a kinetic model. The former employs the cold-electron approximation and the latter incorporates warm-electron effects. The numerical analysis has been performed for pressures in the range 370–770 mTorr and at 450 MHz rf powers below 3.5 W, and then the PIC-MCC results are compared with available experimental data and fluid simulation results. The results show that a considerably thick sheath structure can be seen compared with the plasma reactor size and the electron energy distribution is non-Maxwellian over the entire plasma region. As a result, the distribution of the electron temperature is quite different from that obtained in the fluid model. The electron temperature as a function of rf power is in a reasonable agreement with experimental data. The pressure dependence of the plasma density shows different tendency between the collisional and kinetic model, implying noncollisional effects even at high pressures due to the high rf frequency, where the electron collision frequency is less than the rf driving frequency.
Effects of the impurity–host interactions on the nonradiative processes in ZnS:Cr
Authors: Tablero C.
Published: November 2010

There is a great deal of controversy about whether the behavior of an intermediate band in the gap of semiconductors is similar or not to the deep-gap levels. It can have significant consequences, for example, on the nonradiative recombination. In order to analyze the behavior of an intermediate band, we have considered the effect of the inward and outward displacements corresponding to breathing and longitudinal modes of Cr-doped ZnS and on the charge density for different processes involved in the nonradiative recombination using first-principles. This metal-doped zinc chalcogenide has a partially filled band within the host semiconductor gap. In contrast to the properties exhibited by deep-gap levels in other systems, we find small variations in the equilibrium configurations, forces, and electronic density around the Cr when the nonradiative recombination mechanisms modify the intermediate band charge. The charge density around the impurity is equilibrated in response to the perturbations in the equilibrium nuclear configuration and the charge of the intermediate band. The equilibration follows a Le Chatelier principle through the modification of the contribution from the impurity to the intermediate band and to the valence band. The intermediate band introduced by Cr in ZnS for the concentrations analyzed makes the electronic capture difficult and later multiphonon emission in the charge-transfer processes, in accordance with experimental results.
Large eddy simulation of spray atomization with stochastic modeling of breakup
Authors: Jones W. P. , Lettieri C.
Published: November 2010

A stochastic subgrid model for the droplet breakup in large eddy simulation is developed. An Eulerian description of the continuous phase is adopted and fully coupled with a Lagrangian definition of the dispersed phase. A stochastic model is incorporated into the equation describing the evolution of the spray probability density function in order to simulate the atomization of sprays in the framework of uncorrelated breakup events. The results of the simulations are compared with experimental data from a diesel injector and in spray in cross flows.
Transition from insulator to metal induced by hybridized connection of graphene and boron nitride nanoribbons
Authors: He Jun , Chen Ke-Qiu , Fan Zhi-Qiang , Tang Li-Ming , Hu W. P.
Published: November 2010

A hybridized structure constructed by zigzag boron nitride nanoribbon and zigzag graphene nanoribbon is proposed, and their band structures and electronic transport properties are calculated by applying first-principles calculations. The results show that the band gap of the hybridized structure can be tuned and transitions from insulator to metal can be realized by changing the unit number of zigzag graphene nanoribbon. The currents with different spin polarization display different behavior.
Household-level correlates of condom use among a representative sample of Canadian adolescents
Authors: Marshall Brandon D. L. , Koehoorn Mieke , Shoveller Jean A.
Published: November 2010

Background: The relationship between an adolescent’s micro-environment (e.g. the home) and the likelihood of engagement in sexual risk behaviour is poorly understood. Therefore, we sought to examine the household-level correlates of condom use at last intercourse among a nationally representative sample of Canadian adolescents aged 15 to 19. Methods: Using data from the 2005 Canadian Community Health Survey, we conducted logistic regression analyses to determine whether factors related to characteristics of the household environment were associated with self-reported condom use at last intercourse. Results: Among 3974 sexually active adolescents, condom use at last intercourse was reported by 74.8%. After adjusting for household education and income, participants who reported living in larger dwellings were less likely to report condom non-use, while those reporting greater numbers of persons in the household were more likely to report condom non-use. Other significant correlates of condom non-use included older age, female sex, alternative birth control methods and having a weak sense of community belonging. Conclusion: Our results demonstrate that factors related to the household environment are independently associated with condom use among adolescents. Policies and programs that aim to promote condom use should seek to address issues such as privacy, which may limit adolescents’ ability to engage in safer sexual practices.
The grammaticalization of prospective aspect in a group of Neo-Aramaic dialects
Authors: Coghill Eleanor
Published: November 2010

This paper examines the development of a future (more precisely ‘prospective’) auxiliary from a motion verb in a small group of Neo-Aramaic dialects spoken in Iraq. The long written record of Aramaic allows us to follow the grammaticalization process in some detail, and recent documentation of dialects has shown that various stages co-exist synchronically. The Neo-Aramaic case challenges the theory that future auxiliaries from a verb ‘to go’ should derive from an imperfective in languages which have one. The development of the auxiliary also involves the reanalysis of a present perfect as an immediate future: this apparently surprising development is explained and possible parallels to it in other languages given. The prospective construction exists alongside another future tense and the differences in form and function can be seen to reflect the different origins and ages of the two constructions. There are strong indications that the prospective construction has developed as a result of contact with a similar vernacular Arabic construction. The distribution and level of maturity of the construction in the different dialects can be explained by an origin in a village close to the Arabic-speaking area, and thence diffusion to the neighbouring villages.
Parallel System Borrowing
Authors: Kossmann Maarten
Published: November 2010

In the typology of morphological borrowing, one type has received little attention: cases where words are borrowed in several paradigmatic forms. An example of this is found in English alumnus – alumni, where Latin nouns are borrowed both in their singular and plural forms. Such borrowings lead to a coexistence of borrowed and native paradigms in one and the same language. This type of borrowing is called Parallel System Borrowing (PSB). Such patterns are wide-spread, and concern virtually all parts of morphology, including verbal inflection and pronouns. The emergence of PSB is not governed by a single sociolinguistic factor, such as the existence of learned registers (as with alumnus – alumni). In fact, it appears that some of the most spectacular cases of PSB have no relation to learned registers at all.
“You’re absolutely right!!”
Authors: Carretero Marta
Published: November 2010

The English degree adverb absolutely and its Spanish equivalent absolutamente may function as modifiers of words of different kinds, as Adjuncts and as (parts of) minor clauses. This article sets forth a quantitative analysis, based on naturally-occurring linguistic data, of the distribution of these functions for both adverbs. Apart from distributional differences between the two adverbs and between their occurrences in spoken and written language, the results show that when they are modifiers of words or Verbal Group-oriented Adjuncts, their main function is to qualify (part of) the propositional content of the utterance; however, when they are clausal Adjuncts or (parts of) minor clauses, they are often geared to the performance of discourse functions such as contrast, concession or agreement. These functions are shared with some adverbs of certainty such as ‘certainly’ or ‘definitely’, which suggests that the semantic difference between degree and certainty tends to be blurred when adverbs of maximal strength of both types are used for performing discourse functions that enhance assertiveness.
The FtsH Protease Heterocomplex in Arabidopsis: Dispensability of Type-B Protease Activity for Proper Chloroplast Development
Authors: Zhang Di , Kato Yusuke , Zhang Lingang , Fujimoto Masaru , Tsutsumi Nobuhiro , Sodmergen  , Sakamoto Wataru
Published: November 2010

FtsH is an ATP-dependent metalloprotease present as a hexameric heterocomplex in thylakoid membranes. Encoded in the Arabidopsis thaliana YELLOW VARIEGATED2 (VAR2) locus, FtsH2 is one isoform among major Type A (FtsH1/5) and Type B (FtsH2/8) isomers. Mutants lacking FtsH2 (var2) and FtsH5 (var1) are characterized by a typical leaf-variegated phenotype. The functional importance of the catalytic center (comprised by the zinc binding domain) in FtsH2 was assessed in this study by generating transgenic plants that ectopically expressed FtsH2(488), a proteolytically inactive version of FtsH2. The resulting amino acid substitution inhibited FtsH protease activity in vivo when introduced into Escherichia coli FtsH. By contrast, expression of FtsH2(488) rescued not only leaf variegation in var2 but also seedling lethality in var2 ftsh8, suggesting that the protease activity of Type B isomers is completely dispensable, which implies that the chloroplastic FtsH complex has protease sites in excess and that they act redundantly rather than coordinately. However, expression of FtsH2(488) did not fully rescue leaf variegation in var1 var2 because the overall FtsH levels were reduced under this background. Applying an inducible promoter to our complementation analysis revealed that rescue of leaf variegation indeed depends on the overall amount of FtsH. Our results elucidate protein activity and its amount as important factors for the function of FtsH heterocomplexes that are composed of multiple isoforms in the thylakoid membrane.
Direct observation of arylnitrene formation in the photoreaction of arylazide crystals
Authors: Takayama Terufumi , Mitsumori Takahiro , Kawano Masaki , Sekine Akiko , Uekusa Hidehiro , Ohashi Yuji , Sugawara Tadashi
Published: November 2010

Seven crystal structures of arylazides, 2-azidobiphenyl (2), 4-(4-azidophenyl)butanoic acid (3), 3-azidobenzoic acid (4), N-(4-azidophenyl)acetamide (5), 2,4,6-trichlorophenyl azide (6), 2,5-dibromophenyl azide (7) and 2,4,6-tribromophenyl azide (8), have been analyzed by X-rays. When the crystals were irradiated with UV light at ≃ 80 K, only 2-azidobiphenyl gradually changed its cell dimensions with the retention of the single-crystal form. The crystal structure after photo-irradiation was analyzed by X-rays under the same conditions as those before photo-irradiation. Approximately 20% of the 2-azidobiphenyl molecule was converted to the triplet 2-biphenylnitrene and dinitrogen molecules. The existence of the triplet nitrene was confirmed by ESR and IR measurements. Although the structure of dinitrogen was clearly determined, the nitrene structure was obscure because the nitrene produced was almost superimposed on the original 2-azidobiphenyl. The other six crystals were non-reactive or easily broken when they were exposed to UV light. The different reactivity between 2-azidobiphenyl and the other compounds was successfully explained by the reaction cavity of the azido group.
Comparison of the pharmacokinetics and pharmacodynamics of S‐1 between Caucasian and East Asian patients
Authors: Chuah Benjamin , Goh Boon‐Cher , Lee Soo‐Chin , Soong Richie , Lau Fayce , Mulay Marilyn , Dinolfo Melissa , Lim Siew‐Eng , Soo Ross , Furuie Taro , Saito Kaku , Zergebel Christopher , Rosen Lee S.
Published: November 2010

S‐1 is an oral fluoropyrimidine anti‐neoplastic agent that is converted by CYP2A6 to 5‐fluorouracil (5FU). We prospectively studied the pharmacokinetics and pharmacodynamics of S‐1 in two groups of East Asian and Caucasian patients with solid malignancy refractory to standard chemotherapy, or for which 5FU was indicated, to elucidate differences in relation to CYP2A6 genotype and phenotype. S‐1 was given orally at 30 mg/m2b.i.d. for 14 days every 21 days. Dose normalized AUC0–48 hfor tegafur (P = 0.05) and gimeracil (P = 0.036) were higher in East Asians; conversely, AUC0–48 hof fluoro‐β‐alanine was higher in Caucasians (P = 0.044). Exposure to 5FU was similar in both groups (P = 0.967). Mean cotinine:nicotine ratio was 54% higher in the Caucasian group (P = 0.03), and correlated with oral clearance of tegafur (r = 0.59;P = 0.002). Grade 3/4 gastrointestinal toxicities were more common in Caucasians than Asians (21%vs0%). Treatment with S‐1 yields no significant difference in 5FU exposure between Caucasians and East Asians. (Cancer Sci2011; 102: 478–483)
Molecular heterogeneity of XY sex reversal in horses
Authors: Raudsepp T. , Durkin K. , Lear T. L. , Das P. J. , Avila F. , Kachroo P. , Chowdhary B. P.
Published: November 2010

Male‐to‐female 64,XY sex reversal is a frequently reported chromosome abnormality in horses. Despite this, the molecular causes of the condition are as yet poorly understood. This is partially because only limited molecular information is available for the horse Y chromosome (ECAY). Here, we used the recently developed ECAY map and carried out the first comprehensive study of the Y chromosome in XY mares (n = 18). The integrity of the ECAY in XY females was studied by FISH and PCR using markers evenly distributed along the euchromatic region. The results showed that the XY sex reversal condition in horses has two molecularly distinct forms: (i) a Y‐linked form that is characterized by Y chromosome deletions and (ii) a non‐Y‐linked form where the Y chromosome of affected females is molecularly the same as in normal males. Further analysis of the Y‐linked form (13 cases) showed that the condition is molecularly heterogeneous: the smallest deletions spanned about 21 kb, while the largest involved the entire euchromatic region. Regardless of the size, all deletions included theSRYgene. We show that the deletions were likely caused by inter‐chromatid recombination events between repeated sequences in ECAY. Further, we hypothesize that the occurrence ofSRY‐negative XY females in some species (horse, human) but not in others (pig, dog) is because of differences in the organization of the Y chromosome. Finally, in contrast to the Y‐linkedSRY‐negative form of equine XY sex reversal, the molecular causes ofSRY‐positive XY mares (5 cases) remain as yet undefined.
A genome‐wide scan for tying‐up syndrome in Japanese Thoroughbreds
Authors: Tozaki T. , Hirota K. , Sugita S. , Ishida N. , Miyake T. , Oki H. , Hasegawa T.
Published: November 2010

Tying‐up syndrome, also known as recurrent exertional rhabdomyolysis in Thoroughbreds, is a common muscle disorder for racehorses. In this study, we performed a multipoint linkage analysis using LOKI based on the Bayesian Markov chain Monte Carlo method using 5 half‐sib families (51 affected and 277 nonaffected horses in total), and a genome‐wide association study (GWAS) using microsatellites (144 affected and 144 nonaffected horses) to map candidate regions for tying‐up syndrome in Japanese Thoroughbreds. The linkage analysis identified one strong L‐score (82.45) between the lociUCDEQ411andCOR058(24.9–27.9 Mb) on ECA12. The GWAS identified two suggestive genomic regions on ECA12 (24.9–27.8 Mb) and ECA20 (29.3–33.5 Mb). Based on both results, the genomic region betweenUCDEQ411andTKY499(24.9–27.8 Mb) on ECA12 was the most significant and was considered as a candidate region for tying‐up syndrome in Japanese Thoroughbreds.
Fine mapping of a quantitative trait locus for osteochondrosis on horse chromosome 2
Authors: Dierks C. , Komm K. , Lampe V. , Distl O.
Published: November 2010

In this study, we refine a quantitative trait locus for equine osteochondrosis (OC) on horse chromosome (ECA) 2 to a genome‐wide significant interval at 20.08–30.94 Mb. The marker set contained 27 newly developed microsatellites equidistantly distributed over ECA2 and 44 nucleotide polymorphisms, located in 16 positional candidate genes for OC. Genotyping was performed in 211 Hanoverian horses from 14 paternal half‐sib groups. A NCDN‐associated SNP and haplotype were significantly associated with OC in fetlock and/or hock joints. This study is a further step towards the identification of genes responsible for OC in horses.
Morphological variation in the horse: defining complex traits of body size and shape
Authors: Brooks S. A. , Makvandi‐Nejad S. , Chu E. , Allen J. J. , Streeter C. , Gu E. , McCleery B. , Murphy B. A. , Bellone R. , Sutter N. B.
Published: November 2010

Horses, like many domesticated species, have been selected for broad variation in skeletal size. This variation is not only an interesting model of rapid evolutionary change during domestication, but is also directly applicable to the horse industry. Breeders select for complex traits like body size and skeletal conformation to improve marketability, function, soundness and performance in the show ring. Using a well‐defined set of 35 measurements, we have identified and quantified skeletal variation in the horse species. We collected measurements from 1215 horses representing 65 breeds of diverse conformation such as the American Miniature, Shetland Pony, Arabian Horse, Thoroughbred, Shire and Clydesdale. Principal components analysis has identified two key dimensions of skeletal variation in the horse. Principal component 1 is positively correlated with every measurement and quantifies overall body size. Principal component 2 captures a pattern of bone widths vs. lengths and thus quantifies variation in overall bone thickness. By defining these complex skeletal traits, we have created a framework for whole genome association studies to identify quantitative trait loci that contribute to this variation.
Microarray analysis after strenuous exercise in peripheral blood mononuclear cells of endurance horses
Authors: Capomaccio S. , Cappelli K. , Barrey E. , Felicetti M. , Silvestrelli M. , Verini‐Supplizi A.
Published: November 2010

It is known that moderate physical activity may have beneficial effects on health, whereas strenuous effort induces a state resembling inflammation. The molecular mechanisms underlying the cellular response to exercise remain unclear, although it is clear that the immune system plays a key role. It has been hypothesized that the physio‐pathological condition that develops in athletes subjected to heavy training is caused by derangement of cellular immune regulation. The purpose of the present study was to obtain information on endurance horse gene transcription under strenuous conditions and to identify candidate genes causing immune system derangement. We performed a wide gene expression scan, using microarray technology, on peripheral blood mononuclear cells of ten horses chosen from high‐level participants in national and international endurance races. The use of three different timepoints revealed changes in gene expression when post‐effort samples (T1, taken immediately after the race; and T2, taken 24 h after the race) were compared with basal sample (T0, at rest). Statistical analysis showed no differences in gene expression between T0 and T2 samples, indicating complete restoration of homeostasis by 24 h after racing, whereas T1 showed strong modulation of expression, affecting 132 genes (97 upregulated, 35 downregulated). Ingenuity pathway analysis revealed that the main mechanisms and biofunctions involved were significantly associated with immunological and inflammatory responses. Real‐time PCR was performed on 26 gene products to validate the array data.
Systemic inflammatory responses in progressing periodontitis during pregnancy in a baboon model
Authors: Ebersole J L , Steffen M J , Holt S C , Kesavalu L , Chu L , Cappelli D
Published: November 2010

This study tested the hypothesis that pregnant female baboons exhibit increased levels of various inflammatory mediators in serum resulting from ligature-induced periodontitis, and that these profiles would relate to periodontal disease severity/extent in the animals. The animals were sampled at baseline (B), mid-pregnancy (MP; two quadrants ligated) and at delivery (D; four quadrants ligated). All baboons developed increased plaque, gingival inflammation and bleeding, pocket depths and attachment loss following placement of the ligatures. By MP, both prostaglandin E2 (PGE2) and bactericidal permeability inducing factor (BPI) were greater than baseline, while increased levels of interleukin (IL)-6 occurred in the experimental animals by the time of delivery. IL-8, MCP-1 and LBP all decreased from baseline through the ligation phase of the study. Stratification of the animals by baseline clinical presentation demonstrated that PGE2, LBP, IL-8 and MCP-1 levels were altered throughout the ligation interval, irrespective of baseline clinical values. IL-6, IL-8 and LBP were significantly lower in the subset of animals that demonstrated the least clinical response to ligation, indicative of progressing periodontal disease. PGE2, macrophage chemotactic protein (MCP)-1, regulated upon activation, normal T cell expressed and secreted (RANTES) and LBP were decreased in the most diseased subset of animals at delivery. Systemic antibody responses to Fusobacterium nucleatum, Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Campylobacter rectus were associated most frequently with variations in inflammatory mediator levels. These results provide a profile of systemic inflammatory mediators during ligature-induced periodontitis in pregnant baboons. The relationship of the oral clinical parameters to systemic inflammatory responses is consistent with a contribution to adverse pregnancy outcomes in a subset of the animals.
Forward genetic dissection of innate response to infection in inbred mouse strains: selected success stories
Authors: Gruenheid S , Gros P
Published: November 2010

Mouse genetics is a powerful tool for the dissection of genes, proteins, and pathways important in biological processes. Application of this approach to study the host response to infection has been a rich source of discoveries that have increased our understanding of the early innate pathways involved in responding to microbial infections. Here we review some of the key discoveries that have arisen from pinpointing the genetic defect in mouse strains with unusual or extreme response to infection and have led to insights into pathogen sensing pathways and downstream effector functions of the early innate immune response.
Novel chimeric thyroid-stimulating hormone-receptor bioassay for thyroid-stimulating immunoglobulins
Authors: Lytton S D , Li Y , Olivo P D , Kohn L D , Kahaly G J
Published: November 2010

Thyroid-stimulating immunoglobulins (TSI) are a functional biomarker of Graves' disease (GD). To develop a novel TSI bioassay, a cell line (MC4-CHO-Luc) was bio-engineered to constitutively express a chimeric TSH receptor (TSHR) and constructed with a cyclic adenosine monophosphate (cAMP)-dependent luciferase reporter gene that enables TSI quantification. Data presented as percentage of specimen-to-reference ratio (SRR%) were obtained from 271 patients with various autoimmune and thyroid diseases and 180 controls. Sensitivity of 96% and specificity of 99% for untreated GD were attained by receiver operating characteristic analysis, area under the curve 0·989, 95% confidence interval 0·969–0·999, P = 0·0001. Precision testing of manufactured reagents of high, medium, low and negative SRR% gave a percentage of coefficient-of-variation of 11·5%, 12·8%, 14·5% and 15·7%, respectively. There was no observed interference by haemoglobin, lipids and bilirubin and no non-specific stimulation by various hormones at and above physiological concentrations. TSI levels from GD patients without (SRR% 406 ± 134, mean ± standard deviation) or under anti-thyroid treatment (173 ± 147) were higher (P < 0·0001) compared with TSI levels of patients with Hashimoto's thyroiditis (51 ± 37), autoimmune diseases without GD (24 ± 10), thyroid nodules (30 ± 26) and controls (35 ± 18). The bioassay showed greater sensitivity when compared with anti-TSHR binding assays. In conclusion, the TSI-Mc4 bioassay measures the functional biomarker accurately in GD with a standardized protocol and could improve substantially the diagnosis of autoimmune diseases involving TSHR autoantibodies.
Activated CD8+ T cells contribute to clearance of gastric Cryptosporidium muris infections
Authors: KVÁČ M. , KODÁDKOVÁ A. , SAK B. , KVĚTOŇOVÁ D. , JALOVECKÁ M. , ROST M. , SALÁT J.
Published: November 2010

The role of CD4+ and CD8+ T lymphocytes in the development of a protective immune response against Cryptosporidium muris infection was studied by the reconstitution of severe combined immunodeficient (SCID) mice with well‐defined populations of either naive or immune CD8+ or CD4+ T lymphocytes. Adoptive transfer of both naive and immune CD4+ T lymphocyte subpopulations protects SCID mice against cryptosporidiosis. Moreover, a significant biological impact of activated CD8+ T cells against gastric cryptosporidiosis was observed. The significant difference in the course and intensity of the infection in reconstituted SCID mice was found to be dependent on the protective function of both the CD4+ and CD8+ T‐cell populations transferred. While SCID mice reconstituted with either immune or naive CD4+ or immune CD8+ T‐cell subpopulations resolved the infection within 29, 37 and 51 days post‐infection, respectively, those reconstituted with naive CD8+ T cells suffered from chronic infection similar to control SCID mice. Reconstitution with CD4+ T cells resulted in suppression of oocyst excretion and shortening of patent period in comparison with SCID mice reconstituted with CD8+ T cells. Thus, although CD4+ T cells are considered important in protective immunity, our results are the first to demonstrate the involvement of activated CD8+ T lymphocytes in the protection of mice against gastric cryptosporidiosis.
Enhanced formation of methane in plant cell cultures by inhibition of cytochrome c oxidase
Authors: WISHKERMAN ASHER , GREINER STEFFEN , GHYCZY MIKLÓS , BOROS MIHÁLY , RAUSCH THOMAS , LENHART KATHARINA , KEPPLER FRANK
Published: November 2010

The claim of methane (CH4) formation in plants has caused much controversy and debate within the scientific community over the past 4 years. Here, using both stable isotope and concentration measurements, we demonstrate that CH4 formation occurs in plant cell cultures that were grown in the dark under sterile conditions. Under non‐stress conditions the plant cell cultures produced trace amounts [0.3–0.6 ng g−1 dry weight (DW) h−1] of CH4 but these could be increased by one to two orders of magnitude (up to 12 ng g−1 DW h−1) when sodium azide, a compound known to disrupt electron transport flow at the cytochrome c oxidase (complex IV) in plant mitochondria, was added to the cell cultures. The addition of other electron transport chain (ETC) inhibitors did not result in significant CH4 formation indicating that a site‐specific disturbance of the ETC at complex IV causes CH4 formation in plant cells. Our study is an important first step in providing more information on non‐microbial CH4 formation from living plants particularly under abiotic stress conditions that might affect the electron transport flow at the cytochrome c oxidase in plant mitochondria.
Importance of volcanic glass alteration to sediment stabilization: offshore Japan
Authors: WHITE RUSSELL J. , SPINELLI GLENN A. , MOZLEY PETER S. , DUNBAR NELIA W.
Published: November 2010

A minor amount (ca 1 wt%) of amorphous silica cement sourced from volcanic glass inhibits consolidation of hemipelagic sediment approaching the Nankai Trough subduction zone throughout the Shikoku Basin. The distribution and nature of the cement were examined via secondary and backscattered electron imaging. The amorphous silica occurs as altered material in contact with volcanic glass, coating grains (including grain contacts) and filling pores. Based on chemical and petrographic evidence, the cement is probably sourced from volcanic glass; this is in contrast to a previous suggestion that this silica cement is sourced dominantly from biogenic silica. Amorphous silica sourced from disseminated volcanic glass shards has the ability to form a thin coating on clay‐dominated sediment throughout the Shikoku Basin. Measured amorphous silica content in hemipelagic sediments suggests that the cementing process is active throughout the Shikoku Basin (at sites separated by >500 km). The cementation process may occur in other locations where sediment containing hydrated disseminated volcanic glass is buried sufficiently for heat to facilitate alteration (i.e. Central America, Cascadia and the Gulf of Alaska).
Malignant transformation of intracranial meningeal melanocytoma. Case report and review of the literature
Authors: Wang Fulin , Qiao Guangyu , Lou Xin , Song Xin , Chen Wei
Published: November 2010

Meningeal melanocytoma is an uncommon pigmented neoplasm that affects the CNS and develops in the cranial and spinal leptomeninges. Here we report on a case of malignant transformation of intracranial supratentorial meningeal melanocytoma which recurred after 3 years as malignant melanoma. This case demonstrates that the biological behavior of melanocytoma is uncertain and that these lesions may recur as malignant melanoma.
Late‐onset incontinence in a cohort of radical prostatectomy patients
Authors: Naselli Angelo , Simone Giuseppe , Papalia Rocco , Gallucci Michele , Introini Carlo , Andreatta Rossana , Puppo Paolo
Published: November 2010

A cohort of 235 subjects, who underwent radical prostatectomy from 1994 to 2002, completely continent at the 2‐year follow up and with the last follow‐up visit in 2009, was examined to assess incidence and risk factors of late‐onset incontinence. Median follow up was 100 months, range 84–176. At the last follow‐up visit, 209 (89%) maintained continence, and 26 (11%) became incontinent. Specifically 14 out of 26 (6%) used one pad and 12 (5%) used two or more pads daily. Incidence of age ≥65 years at radical prostatectomy was greater in the subgroup who developed late incontinence, 109/209 (52%) vs 19/26 (73%). Incidence of adjuvant or salvage radiotherapy, of hormonal manipulation and of extraprostatic disease was similar in the two subgroups. Univariate and multivariate analysis did not disclose any difference. Late‐onset incontinence is to be expected in about 10% of subjects who became completely continent after radical prostatectomy. The cause is likely to be related to ageing. Patients should be informed about the long‐term risk of becoming incontinent.
Transanal repair for treatment of rectocele in obstructed defaecation: manual or stapled
Authors: Mahmoud S. A. , Omar W. , Farid M.
Published: November 2010

Aim  Our aim is to evaluate the results of transanal repair of rectocele, either manual or stapled, considering the anatomic, manometric and symptomatic improvement.

Methods  Forty‐five female patients with obstructed defaecation due to anterior rectocele were operated on in the Colorectal Surgery Unit, Mansoura University Hospital, after history taking, detailed questionnaire analysis, barium enema, anorectal manometric studies, EMG studies, anal endosonography, balloon expulsion test, colonic transit time and defaecographic studies. Transanal manual repair was performed for 23 patients (group 1), and transanal stapled repair (group 2) was performed for 22 patients. Postoperative complications were recorded, and the patients were followed up for 1 year. Functional results were evaluated at 3, 6 and 12 months after surgery by questionnaire, anorectal manometry and evacuation proctography.

Results  Time of operation and hospital stay were significantly shorter in group 2. Postoperatively, there was no mortality or major morbidity. Two patients in group 1 experienced temporary anal incontinence (A3 and B1 stages). There were no reported adverse effects on sexual life, but significant clinical improvement was observed in both groups after surgery. Manometrically, there was a significant improvement in MARP, FLAC, RS, UTDV and MTV in both groups (significantly better in the early postoperative period in the stapled group). Also, follow‐up defaecographic findings showed a significant decrease in the rectocele size in all the patients.

Conclusion  Transanal repair of rectocele is a safe and effective technique in improving symptomatic rectocele. Stapled repair offers the advantage of short operative time, no comorbidity, and shorter hospital stay.
C‐reactive protein is a strong predictor for anaemia in renal cell carcinoma: role of IL‐6 in overall survival
Authors: Falkensammer Claudia E. , Thurnher Martin , Leonhartsberger Nicolai , Ramoner Reinhold
Published: November 2010

Study Type – Prognostic (case series)

Level of Evidence 4

What’s known on the subject? and What does the study add?

The incidence of renal cell carcinoma (RCC)‐associated anaemia has been linked with more aggressive tumours. Metastatic RCC patients with elevated IL‐6 levels have significantly decreased haemoglobin concentrations.

We elucidate the association of progression of advanced RCC with anaemia and different factors influencing tumour‐associated anaemia. Interleukin‐6 emerges as a possible target to treat cancer‐related anaemia in metastatic RCC.

OBJECTIVE

• To elucidate the association of progression of advanced renal cell carcinoma with anaemia and investigate factors influencing tumor‐associated anaemia.

PATIENTS AND METHODS

• We analyzed different clinical variables to study associations with anaemia in 86 metastatic renal cell carcinoma patients.

• 45 (52%) of patients had already developed anaemia prior to therapy.

RESULTS

• Anaemic patients had an increase in the serum markers C‐reactive protein (CRP), IL‐6 and erythropoietin (EPO). In addition we observed substantial correlation between IL‐6 and CRP serum levels (R = 0.639, P < 0.0001).

• Univariate logistic regression analysis revealed that patients with IL‐6 >10 pg/mL had a considerable increase in risk for anaemia (odds ratio 3.86, P= 0.003).

• In addition, patients with CRP >0.7 mg/dL had a very strong increase in risk for anaemia (OR = 14.08, P < 0.0001).

• Stepwise multivariate logistic regression analysis confirmed CRP >0.7 mg/mL as the only independent predictor for anaemia. Cox‐regression modeling selected serum IL‐6 as the strongest independent prognostic indicator (hazard ratio 3.58, P < 0.0001).

CONCLUSION

• Anaemia depends on serum IL‐6, which is a strong inductor of CRP and regulator of the iron‐transport. Serum IL‐6 may be considered as a target to treat cancer‐related anaemia.
Dorothy Hodgkin Lecture 2010^. From hype to hope? A journey through the genetics of Type 2 diabetes
Authors: McCarthy M. I.
Published: November 2010

Diabet. Med. 28, 132–140 (2011)

Recent advances in genetic analysis have enabled researchers to perform genome‐wide surveys for common DNA sequence variants associated with risk of Type 2 diabetes and related traits. Over the past 4 years, these endeavours have extended the number of proven Type 2 diabetes‐susceptibility loci from a handful to the current total of over 40. Each of these loci provides an opportunity to uncover insights into the biology of glucose regulation and the pathogenesis of Type 2 diabetes, insights which should support clinical translation to identify novel ways of treating and preventing disease. Here, I describe (i) progress in identification of diabetes‐susceptibility loci; (ii) biological insights that have been gained in the relatively short period since these loci were discovered; and (iii) the challenges that need to be addressed if we are to maximize the translational benefits of this research.
A new hybrid recommendation algorithm with privacy
Authors: Renckes Sahin , Polat Huseyin , Oysal Yusuf
Published: November 2010

Providing accurate and dependable recommendations efficiently while preserving privacy is essential for e‐commerce sites to recruit new customers and keep the existing ones. Such sites might be able to increase their sales and profits while customers can obtain precise and trustworthy predictions if they use appropriate collaborative filtering (CF) algorithms without deeply jeopardizing users' privacy. We propose a new recommendation algorithm, which is a hybrid‐memory and model‐based algorithm to generate truthful referrals efficiently. Moreover, we use randomization techniques to preserve users' privacy while still offering CF services with decent accuracy. We perform real data‐based trials and analyse our proposed schemes in terms of privacy, accuracy, and performance.