bluuebunny/crossref_metadata_2025 huggingface dataset:
National Elements in the Career of St. Athanasius
Authors: Hardy Edward Rochie
Published: July 2009

It has been recognized for some time that nationalism is a factor to be reckoned with in the ecclesiastical history of the later Roman Empire. Certainly the history of the Monophysites after Chalcedon is largely the story of the struggle of Egyptian and Syrian national feeling against the Empire. In all probability the bishops of Alexandria who in the two generations before Chalcedon combatted the rise of the imperial church at Constantinople— Theophilus, Cyril, and Dioscorus—were supported by the patriotism of the Egyptian nation as well as by the pride of the Alexandrian see. But there has not yet been any answer to the question, when did this union of Christianity and nationalism in Egypt begin?

The discussion of this problem involves interrogating our sources on a subject they do not consciously treat and must be a matter of interpretation rather than merely of quotation of evidence. The problem could be stated in two ways; the church historian asks, when did Egyptian Christianity become nationalist? while for Egyptian history the problem is, when did Egyptian nationalism become Christian? The Egyptian nation, with its language, its religion, and some remnants of its literature and culture, had continued to exist through the whole period of Greco-Roman dominance. In the Coptic church it was to find once more the means to vigorous self-expression.
The Ultramontanism of Saint Boniface
Authors: Higgins John Seville
Published: July 2009

Professor Becker has said “The migrations of the Teutonic tribes and the expansion of the Saracens together form the basis of the history of the Middle Ages.” The Muslim conquests of Persia, Egypt, North Africa and Spain from 634 to 713 wiped out the ancient sees of Ephesus, Antioch, Jerusalem, and Alexandria. Only Rome remained. The Saracens continued their advance over the Pyrenees and did not receive their first severe check until Charles Martel met and defeated them at Tours in 732. It was several more years however before Charles was able to regain Provence and secure Aquitaine against invasion.
Early Relations of Baptists and Quakers
Authors: Harkness R. E. E.
Published: July 2009

On a little hillside that rises abruptly from the Baltimore Pike, an old highway from Philadelphia to Baltimore, some fifty miles south of Philadelphia, stands a little old meeting-house a-round which gather many interesting historical incidents. It is the home of the Brandywine Baptist Church, on the edge of the famous Brandywine battle field where Washington, joined for the first time by Lafayette, met defeat by the British under Howe and Cornwallis and was forced to abandon Philadelphia, September 11, 1777. Giant oak trees tower high on the hillside to-day and members of the church will point out the one against which, according to tradition, the young French general leaned, severely wounded.
Anglicanism on the Eve of the Oxford Movement
Authors: McNeill John T.
Published: July 2009

1. The Erastian Bondage of the Church:

The promise of Magna Charta “that the English Church shall be free and have her rights entire and her liberties inviolate,” went largely unfulfilled. The autonomy of the Church was dreamt of by men like Stephen Langton and Robert Grosseteste, but it was never realized. In the Middle Ages it was restricted by the assertion of the jurisdiction of the Pope on the one hand, and of the King on the other. Magna Charta marked the humiliation of the King and met with the prompt condemnation of the Pope. By a long series of events between ca. 1350 and ca. 1570, the Pope's cause in England was lost, and in the same course of events the royal power was greatly enhanced. So far as constitutional autonomy was concerned the Church was now in a weaker state than before. The gates of a prison-house of Erastianism closed about her. A blight fell upon her governing institutions. Her Convocations were not permitted to function, and after 1718 were discontinued, except for pro forma meetings held for the purpose, as Edmund Burke phrased it, “of making some polite ecclesiastical compliments to the King.” Burke spoke for the politicians of his century when he added: “It is wise to permit its legal existence only.” Because Convocation's last acts had been attended by strife, the fear that its revival would mean a renewal of unseemly contention was habitually invoked as an answer to the few who ventured to suggest that step.
The Conception of Authority in the Oxford Movement
Authors: Harris T. L.
Published: July 2009

In the past, church historians have too often neglected the influence of social forces on the development of theological ideas. I propose therefore to study the Tractarians' conception of authority with reference to their social environment rather than with reference to their theological heredity.
Recent Recognition of Archbishop Peckham—Bibliographical
Authors: Peckham John L.
Published: July 2009

Since the opening of the century there has been a marked awakening of interest in the works of John Peckham and an increasing appreciation of his importance in many areas of medieval life and thought. As lecturer at Paris and Rome, as Provincial Minister of the Franciscans in England, and as Archbishop of Canterbury, this active and learned scholar devoted his attention to many literary and executive tasks, making substantial contributions in such varied fields as theology, philosophy, religious education, homiletics, canon law, Franciscan history, science, liturgies, and poetry.
The Significance to Church History of the Change from the Temporary to the Permanent in Foreign Missions
Authors: Schermerhorn William D.
Published: July 2009

It is an interesting matter of conjecture just how long it would have taken for John the Baptist to transfer the leadership of the religious group which he founded to Jesus, if John had kept free from the toils of the Roman law and Herod had not set him aside. Judging by the persistence of the John cult among the churches of the East we may believe that the process would have been slow. Just so the modern missionary, whose era may be dated during the past one hundred and fifty years, although he has always announced that his rôle was that of John the Baptist, has nevertheless moved slowly in helping the national leaders to “increase” while he “decreased.”
Asceticism Versus Militarism in the Middle Ages
Authors: McNeill John T.
Published: July 2009

The terms “religion” and “asceticism” represent separable realms of experience. Asceticism may occur where a Stoic philosopher, from purely ethical considerations, denies all indulgence to the appetites of the body, that “gaol and shackle of the soul.” It is today employed, in Egypt and in India, in the strategy of political causes. The athlete or the actor, the scholar or the merchant, may adopt an ascetic type of behavior for the sake of efficiency on a non-religious level. On the other hand feasting may be as religious as fasting, jubilation as holy as penance.
The Plan of Union in New York
Authors: Nichols Robert Hastings
Published: July 2009

The history of the Plan of Union has been written largely under the influence of denominational zeal, jealousy, and antipathy. Underlying much of the writing have been the assumptions that a main object of religious endeavor is to build up denominational organizations and enlarge the statistics, that denominations ought to be kept “pure,” that movements of individuals or churches from one to another are not altogether creditable and justify suspicion of inferior motives on the part of somebody. For example, the Rev. James H. Dill, in an article on “Congregationalism in Western New York” in theCongregational Quarterlyin 1859, which has recently been cited as an authority, refers to churches “which have been spirited away from Congregationalism”; and Dr. Joseph P. Thompson, in an article on “Congregationalism in Eastern New York” in the same periodical in 1860, says “The Black River Association … had increased to seventeen churches when in 1817, it was induced to unite with the Watertown Presbytery. … After some years, some of the Congregational churches withdrew from this entanglement, and re-organized in an Association.” On the other side, Dr. Samuel J. Baird in 1868 said inA History of the New School, “The multiplication of Congregational ministers, in the Presbyterian Church, was no increase of strength; but the introduction of an element of weakness, division and heresy.”
Trading on faith: religious movements and informal economic governance in Nigeria
Authors: Meagher Kate
Published: July 2009

The pressures of economic crisis and reform that have gripped African societies have been accompanied by a proliferation of new religious movements. Amid concerns about the political impact of religious revivalism, little attention has been devoted to their economic implications. Focusing on the remarkable coincidence between the withdrawal of the state, the rise of religious movements, and the dramatic expansion of the informal economy, this paper examines the role of religious revivalism in processes of informal economic governance and class formation in contemporary Africa. Against the background of the historical role of religion in the development of market institutions across the continent, it traces the dynamics of religious revivalism and informal economic regulation in two regions of Nigeria. Rather than representing a return to occultist or patrimonial impulses, new religious movements reveal distinctly Weberian tendencies. However, modernising tendencies fostered within the informal economy by popular religious revivalism are being stunted by the relentless pressures of liberalisation, globalisation and pseudo-democratisation. Progressive religious tendencies among the poor are being instrumentalised by religious entrepreneurs and political elites, undermining fragile processes of entrepreneurial class formation taking place within the informal economy.
An Ontology-Based Framework for Clinical Research Databases
Authors: Scheuermann Richard H. , Kong Megan , Dahlke Carl , Karp David
Published: July 2009

The Ontology-Based eXtensible data model (OBX) was developed to serve as a framework for the development of a clinical research database in the Immunology Database and Analysis Portal (ImmPort) system. OBX was designed around the logical structure provided by the Basic Formal Ontology (BFO) and the Ontology for Biomedical Investigations (OBI). By using the logical structure provided by these two well-formulated ontologies, we have found that a relatively simple, extensible data model could be developed to represent the relatively complex domain of clinical research. In addition, the common framework provided by the BFO should make it straightforward to utilize OBX database data dictionaries based on reference and application ontologies from the OBO Foundry.
An exercise on developing an ontology-epistemology about schizophrenia and neuroanatomy
Authors: Freire Rodolpho , Santos Danilo Nunes , Vinicius dos Santos Marcos , Eduardo Santos Paulo
Published: July 2009

This paper describes preliminary ideas on formalizing some concepts of neuroanatomy into ontological and epistemological terms. We envisage the application of this ontology on the assimilation of facts about medical knowledge about neuroimages from schizophrenic patients.
A Nonword Repetition Task for Speakers With Misarticulations: The Syllable Repetition Task (SRT)
Authors: Shriberg Lawrence D. , Lohmeier Heather L. , Campbell Thomas F. , Dollaghan Christine A. , Green Jordan R. , Moore Christopher A.
Published: July 2009

Purpose

Conceptual and methodological confounds occur when non(sense) word repetition tasks are administered to speakers who do not have the target speech sounds in their phonetic inventories or who habitually misarticulate targeted speech sounds. In this article, the authors (a) describe a nonword repetition task, the Syllable Repetiton Task (SRT), that eliminates this confound and (b) report findings from 3 validity studies.

Method

Ninety-five preschool children with speech delay and 63 with typical speech completed an assessment battery that included the Nonword Repetition Task (NRT; C. Dollaghan & T. F. Campbell, 1998) and the SRT. SRT stimuli include only 4 of the earliest occurring consonants and 1 early occurring vowel.

Results

Study 1 findings indicated that the SRT eliminated the speech confound in nonword testing with speakers who misarticulate. Study 2 findings indicated that the accuracy of the SRT to identify expressive language impairment was comparable to findings for the NRT. Study 3 findings illustrated the SRT’s potential to interrogate speech processing constraints underlying poor nonword repetition accuracy. Results supported both memorial and auditory–perceptual encoding constraints underlying nonword repetition errors in children with speech-language impairment.

Conclusion

The SRT appears to be a psychometrically stable and substantively informative nonword repetition task for emerging genetic research and other research with speakers who misarticulate.
Speech Perception Abilities of Adults With Dyslexia: Is There Any Evidence for a True Deficit?
Authors: Hazan Valerie , Messaoud-Galusi Souhila , Rosen Stuart , Nouwens Suzan , Shakespeare Bethanie
Published: July 2009

Purpose

This study investigated whether adults with dyslexia show evidence of a consistent speech perception deficit by testing phoneme categorization and word perception in noise.

Method

Seventeen adults with dyslexia and 20 average readers underwent a test battery including standardized reading, language and phonological awareness tests, and tests of speech perception. Categorization of a pea/bee voicing contrast was evaluated using adaptive identification and discrimination tasks, presented in quiet and in noise, and a fixed-step discrimination task. Two further tests of word perception in noise were presented.

Results

There were no significant group differences for categorization in quiet or noise, across- and within-category discrimination as measured adaptively, or word perception, but average readers showed better across- and within-category discrimination in the fixed-step discrimination task. Individuals did not show consistent poor performance across related tasks.

Conclusions

The small number of group differences, and lack of consistent poor individual performance, suggests weak support for a speech perception deficit in dyslexia. It seems likely that at least some poor performances are attributable to nonsensory factors like attention. It may also be that some individuals with dyslexia have speech perceptual acuity that is at the lower end of the normal range and exacerbated by nonsensory factors.
Dynamics behavior of homogeneous dielectric barrier discharge at atmospheric pressure
Authors: Zhang Yan , Gu Biao , Wang Wenchun , Wang Dezhen , Peng Xuwen
Published: July 2009

An experimental study on the dynamics behavior of homogeneous dielectric barrier discharge (HDBD) at atmospheric pressure is described in this paper. Two kinds of discharge mode, glow and Townsend discharge modes, can be easily identified according to the differential conductivity of current-voltage relationship in the ascent stage of discharge current for the atmospheric HDBD. A (three-dimensional) 3D phase space made by discharge current, gas gap voltage, and charge density of dielectric-plate surface was utilized in the study. By projecting the discharge evolution trajectory in the 3D space, the 3D trajectory of multiple current peaks discharge in atmospheric helium shows a limited cycle with convolutions and undergoes a series of bifurcation process; however, the 3D trajectory of atmospheric N2 HDBD is a limited cycle without any convolution and bifurcation process. In addition, the first ionization coefficient of working gas plays a key role to determine the discharge mode of atmospheric HDBD, the transition of discharge mode and the dynamics stability of atmospheric HDBD.
Optical and electro-optic properties of micrometric thick lead zirconate titanate films on (Pb0.86,La0.14)TiO3/glass
Authors: Zhu M. M. , Du Z. H. , Ma J.
Published: July 2009

Highly (100)-oriented Pb(Zr0.52,Ti0.48)O3 (PZT) films of up to ∼2.4 μm are deposited on the (Pb0.86,La0.14)TiO3 (PLT)-coated amorphous substrate by one cycle of sputtering and annealing. The films possess fibrous columnar nanostructures and vertically grow on the PLT/glass substrate. Microstructure analysis and property characterization indicate that the films possess very promising optical, waveguiding, and electro-optic (EO) properties, as well as low propagation loss. The transparency of >80% in the range of λ=400–1200 nm and the linear EO coefficient of 341.4 pm/V have been measured in the films. Due to the large EO coefficient and the micrometric thickness, a giant phase retardation of 2.93 rad has been measured under an electric field of 50 kV/mm.
Macroscopic thermoplastic model applied to the high pressure torsion of metallic glasses
Authors: Hóbor Sándor , Kovács Zsolt , Révész Ádám
Published: July 2009

Shear deformation generated temperature rise in metallic glasses is estimated in a macroscopic three-dimensional axial symmetric thermoplastic model. Numerical solution of heat-conduction equation provides the time evolution and spatial distribution of temperature for high pressure torsion in the present paper. We have shown that small sample thickness and/or high deformation rate enables the temperature to exceed the glass transition in the entire sample, yielding a transition of the deformation mode from inhomogeneous to homogeneous viscous flow. However, in other cases only a small temperature increase is predicted in line with literature data.
Degenerately Mo-doped In2O3 nanowire arrays on In2O3 microwires with metallic behaviors
Authors: Wan Qing , Huang Jin , Lu Aixia , Sun Jia
Published: July 2009

Transparent metallic Mo-doped In2O3 nanowires arrays with three dimensionally branched morphology are epitaxially grown on undoped In2O3 microwires by the vapor-liquid-solid growth mode. The room-temperature resistivity and failure-current density of individual degenerately doped nanowire are measured to be 1.43×10−4 Ω cm and 1.57×107 A/cm2, respectively. The breakdown mechanism of the nanowires at high current density is due to resistive heating and melting. Lateral vacuum electron field emission properties of individual nanowire tip are investigated and an ultralow turn-on voltage of 1.28 V and a large field enhancement factor of 1.02×103 are obtained.
Critical point and sound waves in complex plasmas
Authors: Avinash K. , Khrapak S. A. , Morfill G. E.
Published: July 2009

An equation of state for particles in complex plasmas, which includes contributions from plasma background fields and interparticle interactions (electric repulsion and “ion shadow” attraction), is obtained. Using this equation, experimental parameter regimes for the observation of liquid-vapor transitions and a critical point are examined. In addition, it is demonstrated that as in binary fluids, sound waves in complex plasmas do not exhibit critical behavior. Thus, criticality in complex plasmas may have more in common with binary fluids rather than ordinary fluids.
Infrared-induced coherent vibration of a hydrogen-bonded system: Effects of mechanical and electrical anharmonic couplings
Authors: Ishii Kunihiko , Takeuchi Satoshi , Tahara Tahei
Published: July 2009

We have studied IR-induced low-frequency coherent vibration of an intramolecularly hydrogen-bonded molecule, quinizarin, by an ultrashort IR-pump-visible-probe spectroscopy with ∼60 fs time resolution. In this experiment, the IR excitation of the symmetric OH-stretching mode induced a low-frequency vibrational coherence, which was then detected as an oscillation of the visible absorption intensity. The observed oscillation was assigned to a “hydrogen-bond modulating” vibration by the vibrational analysis based on the density functional theory (DFT). Because the vibrational coherence formation by IR excitation requires a substantial anharmonic coupling, we carried out a DFT-based numerical analysis of the anharmonic coupling between the OH-stretching and the low-frequency mode, by evaluating the transition moment of the combination band. We took account of two types of anharmonicities, i.e., the mechanical anharmonicity and the electrical anharmonicity. Although the electrical anharmonicity is often neglected, it was found that the electrical anharmonicity had a comparable contribution to the mechanical anharmonicity, in generation of vibrational coherence of the low-frequency mode in this system. This result indicates general importance of the electrical anharmonicity in strongly hydrogen-bonded systems.
X-ray diffraction and scanning electron microscopic studies on the crystal structure and surface/interface morphology of zinc-octaethylporphyrin films on an indium tin oxide substrate spin coated with 3,4-polyethylenedioxythiophene:polystyrenesulfonate
Authors: Ryuzaki S. , Onoe J.
Published: July 2009

The crystal structure and surface/interface morphology of zinc-octaethylporphyrin [Zn(OEP)] films deposited on an indium tin oxide (ITO) substrate spin coated with 3,4- polyethylenedioxythiophene:polystyrenesulfonate (PEDOT:PSS) have been investigated using x-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. XRD results indicated that there are two kinds of grains with their sizes of approximately 20 nm that is independent of film thickness and substrate temperature. One has a diffraction plane with an interplanar distance of 1.12 nm and with its orientation parallel to the substrate, whereas the other has a diffraction plane with an interplanar distance of 1.24 nm and with that inclined mainly by 60° to the substrate. The abundant ratio of the two grains was controlled to some extent by varying film thickness and substrate temperature. Cross-sectional SEM images showed that a part of Zn(OEP) molecules are incorporated into PEDOT:PSS for its film thickness smaller than 130 nm, while that Zn(OEP) whiskers begin to grow for its film thickness exceeding 130 nm.
Hole mobility enhancement by double-gate mode in ultrathin-body silicon-on-insulator p-type metal-oxide-semiconductor field-effect transistors
Authors: Kobayashi Shigeki , Saitoh Masumi , Uchida Ken
Published: July 2009

Hole mobility enhancement in double-gate (DG) ultrathin-body (UTB) silicon-on-insulator (SOI) p-type metal-oxide-semiconductor field-effect transistors (MOSFETs) is investigated systematically in comparison with single-gate (SG) UTB MOSFETs for various SOI thicknesses (TSOI) ranging from 2 to 30 nm. It is found that mobility in DG mode (μDG) is higher than that in SG mode (μSG) in all the measured ranges of TSOI and the surface carrier concentrations (Ns). In particular, enhancement of mobility of the sub-10-nm-thick TSOI devices is greater at higher Ns. As a result, it is demonstrated that μDG of the 8.1-nm-thick TSOI device is 12.9% greater than the universal mobility when Ns is 6×1012 cm−2. Higher μDG is attributed to the average effective mass reduction in DG mode because of the increased population in the light hole (LH) bands. Careful investigation also clarifies that mobility in the sub-10-nm-thick TSOI devices is enhanced greatly at higher Ns, since the DG mode-induced increase in the hole population in LH bands is enhanced at higher Ns; the reduction in the hole population in LH bands due to the high-Ns-enhanced carrier confinement in the normal direction is larger in SG mode than in DG mode.
Thermal conductivity modeling of compacted type nanocomposites
Authors: Hsieh Tse-Yang , Yang Jaw-Yen , Hong Zuu-Chang
Published: July 2009

Due to different interface densities and arrangements, the compacted type nanocomposites may yield even lower thermal conductivity than embedded type nanocomposites. In this paper, the phonon transport and thermal conductivity in compacted type nanocomposites (nanowires and nanoparticles) are investigated using a deterministic phonon Boltzmann transport equation solver. The effects of interface density and characteristic size on the phonon energy transport in nanocomposites are studied. It is found that the silicon-germanium compacted nanoparticle composites can have lower value of thermal conductivity than that of compacted nanowire composites under the same characteristic size (21.6% lower when the characteristic size is 3 nm).
Seebeck effect in PbTe films and EuTe/PbTe superlattices
Authors: Ishida Akihiro , Yamada Tomohiro , Cao Daoshe , Inoue Yoku , Veis Martin , Kita Takuji
Published: July 2009

Theoretical calculations of the Seebeck coefficients of bulk PbTe and PbTe based superlattices were described in the framework of Boltzmann equation, taking into account temperature dependent band gaps, nonparabolicity, and anisotropy of effective masses. It is shown that the temperature gradient along the superlattice layer works more effectively on the enhancement of the thermoelectric figure of merit than the temperature gradient normal to the superlattice layer. Calculated Seebeck coefficients were compared to the experimental values for n-type PbTe, p-type PbTe, and EuTe/PbTe superlattices. The Seebeck coefficient of p-type PbTe was higher than that of n-type PbTe. The relatively high Seebeck coefficient is explained by the contribution from other extrema in the valence band. The EuTe/PbTe [001] superlattice shows higher Seebeck coefficients than PbTe bulk owing to the large density of states.
The intermolecular potential energy surface of the ground electronic state of the O2–H2 complex
Authors: Fawzy Wafaa M.
Published: July 2009

This work presents the first high level correlated ab initio study of the intermolecular potential energy surface of the ground electronic state of the O2 (X Σ3g−)–H2(X) complex. This computational study was carried out using the CCSD(T) level of theory with the aug-cc-pVXZ basis sets, where X=D, T, Q, and 5. All calculated energies were corrected using the BSSE method. The lowest energy geometry and the shape of the intermolecular potential energy surface showed significant dependence on the size of the basis set as well as the BSSE corrections. The most accurate results were obtained using the CCSD(T)/aug-cc-pVQZ and CCSD(T)/aug-cc-pV5Z combinations with the BSSE corrections. These calculations yield a global minimum of C2v symmetry, where internuclear axes of the O2 and H2 moieties are parallel to each other. For this geometry, the De value is 65.27(30) cm−1, which is in excellent agreement with the CBS limit of 65.14 cm−1. The distance between centers of masses of the H2 and O2 monomers within the complex is 3.225(1) Å. Barrier heights to rotation of the H2 and O2 units by 180° about the axis that connects their centers of masses are 24 and 159 cm−1, respectively. The current results should stimulate microwave spectroscopic detection of the O2–H2 complex.
Ion engineering of embedded nanostructures: From spherical to facetted nanoparticles
Authors: Rizza G. , Dawi E. A. , Vredenberg A. M. , Monnet I.
Published: July 2009

We show that the high-energy ion irradiation of embedded metallic spherical nanoparticles (NPs) is not limited to their transformation into prolate nanorods or nanowires. Depending on their pristine size, the three following morphologies can be obtained: (i) nanorods, (ii) facettedlike, and (iii) almost spherical nanostructures. Planar silica films containing nearly monodisperse gold NPs (8–100 nm) were irradiated with swift heavy ions (5 GeV Pb) at room temperature for fluences up to 5×1013 cm−2. The experimental results are accounted for by considering a liquid-solid transformation of the premelted NP surface driven by the in-plane stress within the ion-deformed host matrix. This work demonstrates the interest of using ion-engineering techniques to shape embedded nanostructures into nonconventional configurations.
Magnetic dead layer in ferromagnetic manganite nanoparticles
Authors: Curiale J. , Granada M. , Troiani H. E. , Sánchez R. D. , Leyva A. G. , Levy P. , Samwer K.
Published: July 2009

We present experimental evidence on the physical origin of a magnetic dead layer (MDL) in manganite nanoparticles. The studied nanoparticles constitute the wall of La0.67Sr0.33MnO3 and La0.67Ca0.33MnO3 manganite nanotubes. Magnetic properties analysis and high resolution transmission electron microscopy show a shell of approximately 2 nm thickness with different properties from the core. In this shell the atoms are in a noncrystalline array that perfectly explains the 50% reduction of the magnetization compared to the bulk. Moreover, we present experimental evidence that the internal magnetic structure of the MDL is constituted by small ferromagnetic clusters in a frustrated configuration.
Long baseline planar superconducting gradiometer for biomagnetic imaging
Authors: Granata C. , Vettoliere A. , Nappi C. , Lisitskiy M. , Russo M.
Published: July 2009

A niobium based dc-superconducting quantum interference device (SQUID) planar gradiometer with a long baseline (50 mm) for biomagnetic applications has been developed. The pickup antenna consists of two integrated rectangular coils connected in series and magnetically coupled to a dc-SQUID in a double parallel washer configuration by two series multiturn input coils. Due to a high intrinsic responsivity, the sensors have shown at T=4.2 K a white magnetic flux noise spectral density as low as 3 μΦ0/Hz1/2. The spectral density of the magnetic field noise referred to one sensing coil, is 3.0 fT/Hz1/2 resulting in a gradient spectral noise of 0.6 fT/(cm Hz1/2). In order to verify the effectiveness of such sensors for biomagnetic applications, the magnetic response to a current dipole has been calculated and the results have been compared with those of an analogous axial gradiometer. The results show that there is no significant difference. Due to their high intrinsic balance and good performances, planar gradiometers may be the elective sensors for biomagnetic application in a soft shielded environment.
Resonant coupling of quantum dot intersublevel transitions with midinfrared photonic crystal modes
Authors: Homeyer E. , Houel J. , Checoury X. , Delgehier F. , Sauvage S. , Boucaud P. , Braive R. , Le Gratiet L. , Leroy L. , Miard A. , Lemaître A. , Sagnes I.
Published: July 2009

We show that quantum dot intersublevel transitions can be coupled to midinfrared photonic crystal modes. The coupling is observed under optical pumping with S-P intersublevel transitions of InGaAs self-assembled quantum dots resonant around 20 μm wavelength. An enhancement in the intersublevel absorption and a spectral tuning are evidenced when the optical modes of two-dimensional photonic crystals enter in resonance with the photoinduced intersublevel absorption. This effect is illustrated in the case of GaAs two-dimensional photonic crystal membranes with lattice periodicities of 10.5, 9.5, and 8.5 μm containing multilayers of self-assembled quantum dots.
Photoconductance of aligned SnO2 nanowire field effect transistors
Authors: Kim DaeIl , Kim Yong-Kwan , Park Sung Chan , Ha Jeong Sook , Huh Junghwan , Na Junhong , Kim Gyu-Tae
Published: July 2009

We report on the optoelectronic properties of the aligned SnO2 nanowire (NW) field effect transistors (FETs) fabricated via a sliding transfer of NWs grown by chemical vapor deposition. Photocurrent measurements with polarized UV light confirmed a well aligned NWs along the channels. UV photosensitivity of ∼107 at the gate voltage Vg=−40 V was obtained due to a small dark-current at the turn-off state of FET. The dynamic response of the photocurrent became faster for the higher mobility SnO2 NW FETs. We expect our aligned SnO2 NW FETs will be useful as polarized UV detectors with a high sensitivity.
Modulational instability and envelope excitation of ion-acoustic waves in quantum electron-positron-ion plasmas
Authors: Misra A. P. , Bhowmik C. , Shukla P. K.
Published: July 2009

The theoretical study of modulational instability (MI) and localized envelope excitations of finite amplitude ion-acoustic waves (IAWs) is revisited in an unmagnetized quantum electron-positron-ion plasma. For this purpose, a one-dimensional nonlinear Schrödinger equation, which governs the slow modulation of IAW packets, is derived by using the standard reductive perturbations technique. Two parameters, defining the ratio of the electron to ion number density (μ) and the quantum coupling parameter (H) describing the ratio of the “plasmonic energy density” to the Fermi energy density, are shown to play crucial roles in determining the modulational stability/MI domains, as well as for the existence of both bright and dark envelope solitons. It is found that the stability region increases (decreases) with increasing μ(H), whereas the MI region for the IAW mode shifts to larger (smaller) wave number k as the value of μ(H) increases. Moreover, the parameter H is shown to suppress the MI growth rate of the IAWs. The present results may be relevant to dense astrophysical plasmas (e.g., white dwarfs, where the electron-positron annihilation can be important, and where the particle density is of the order of 1034–1035 m−3) as well as to the next generation intense laser solid density plasma experiments.
Production of size-controlled Si nanocrystals using self-organized optical near-field chemical etching
Authors: Yatsui Takashi , Ohtsu Motoichi
Published: July 2009

We demonstrate the selective photochemical etching of Si in a self-organized manner, which strongly depends on the distribution of the optical near field. This dependence was described by the virtual exciton-phonon-polariton model. The photoluminescence (PL) spectra from the etched Si exhibited a blueshifted PL peak at 1.8 eV, corresponding to Si nanocrystals of 2.8 nm diameter.
The sign problem in real-time path integral simulations: Using the cumulant action to implement multilevel blocking
Authors: Mak C. H.
Published: July 2009

A practical method to tackle the sign problem in real-time path integral simulations is proposed based on the multilevel blocking idea. The formulation is made possible by using a cumulant expansion of the action, which in addition to addressing the sign problem, provides an unbiased estimator for the action from a statistically noisy sample of real-time paths. The cumulant formulation also allows the analytical gradients of the action to be computed with little extra computational effort, and it can easily be implemented in a massively parallel environment.
Mean shear flows generated by nonlinear resonant Alfvén waves
Authors: Clack Christopher T. M. , Ballai Istvan
Published: July 2009

In the context of resonant absorption, nonlinearity has two different manifestations. The first is the reduction in amplitude of perturbations around the resonant point (wave energy absorption). The second is the generation of mean shear flows outside the dissipative layer surrounding the resonant point. Ruderman et al. [Phys. Plasmas 4, 75 (1997)] studied both these effects at the slow resonance in isotropic plasmas. Clack et al. [Astron. Astrophys. 494, 317 (2009)] investigated nonlinearity at the Alfvén resonance; however, they did not include the generation of mean shear flow. In this present paper, we investigate the mean shear flow, analytically, and study its properties. We find that the flow generated is parallel to the magnetic surfaces and has a characteristic velocity proportional to ϵ1/2, where ϵ is the dimensionless amplitude of perturbations far away from the resonance. This is, qualitatively, similar to the flow generated at the slow resonance. The jumps in the derivatives of the parallel and perpendicular components of mean shear flow across the dissipative layer are derived. We estimate the generated mean shear flow to be of the order of 10 km s−1 in both the solar upper chromosphere and solar corona; however, this value strongly depends on the choice of boundary conditions. It is proposed that the generated mean shear flow can produce a Kelvin–Helmholtz instability at the dissipative layer which can create turbulent motions. This instability would be an additional effect, as a Kelvin–Helmholtz instability may already exist due to the velocity field of the resonant Alfvén waves. This flow can also be superimposed onto existing large scale motions in the solar upper atmosphere.
Oxic - anoxic transition of benthic fluxes from the coastal marine environment (Gulf of Trieste, northern Adriatic Sea)
Authors: Faganeli Jadran , Ogrinc Nives
Published: July 2009

The influence of O2 concentration on mineralisation processes was examined by sediment incubation experiments under controlled laboratory conditions over a sequence of oxic, anoxic and then reoxidising conditions. Sediments were studied from five locations representing marine, lagoonal and brackish environments in the Gulf of Trieste (northern Adriatic Sea). A complete depletion of dissolved O2 and nitrate were observed after ~6 –15 days in marine and lagoonal sediments, and after 5 days in brackish sediments. During the reoxygenation phase, nitrification occurred at some sites, as evidenced by increases in NO3– concentrations, but not at other sites, indicating an inhibited recovery response to intermittent oxic conditions. NH4+ and PO43– regeneration during mineralisation was much more extensive in sediments overlain by oxygen-depleted waters, driving additional eutrophication. During reoxygenation, an influx of phosphate was observed in all three sedimentary environments, removing soluble phosphorus through coagulation and finally precipitation. Two degraded organic matter (OM) types could be distinguished: OM degraded under oxic conditions in marine and brackish sediments v. OM rapidly degraded under anoxic conditions in lagoon sediments.
Sediment deposition and net phosphorus retention in a hydraulically restored lowland river floodplain in Denmark: combining field and laboratory experiments
Authors: Kronvang Brian , Hoffmann Carl C. , Dröge Rianne
Published: July 2009

Restoration of river systems allowing the transformation of former drained and dry riparian areas into riparian wetlands will increase the overbank storage of sediment and sediment-associated phosphorus (P). Wetland restoration is therefore a cost-effective mitigation measure to reduce the sediment and nutrient transport to river systems. The studied floodplain of the River Odense was restored in 2003 by remeandering the river channel along a 6-km reach. The restoration project involved 78 ha of riparian areas that were transformed from mainly arable land to extensive grassland and wetlands. The aim of the study was to quantify and model sediment and particulate P deposition on restored river floodplains. The present study suggests that during a 47-day flooding period, the river floodplain is able to retain 9–14.8% of the sediment and 1.1–3.7% of the particulate P transported in the river. Incubation experiments further showed that a maximum of 11–25% of the deposited phosphorus can be released as dissolved inorganic phosphorus following deposition. The results from the best deposition model (R2 = 0.42 for sediment and R2 = 0.44 for particulate P) show that work should be done to further improve the performance of these models.
Sediment diagenesis and porewater solute fluxes in acidic mine lakes: the impact of dissolved organic carbon additions
Authors: Read Deborah J. , Oldham Carolyn E. , Myllymäki Tiina , Koschorreck Matthias
Published: July 2009

Sediment diagenesis through microbial sulfate reduction is considered a critical process in the pH amelioration of acidic mine lakes, but is often limited by the availability of organic carbon. Organic substrates are therefore frequently added to mine lake sediments to stimulate sulfate reduction. Dissolved organic carbon (DOC) was added to sediment collected from three mine lakes, one (in Germany) with typically high concentrations of Fe and SO4 and another two (in Australia) with unusually low concentrations of Fe and SO4. After the DOC additions caused the dissolved oxygen concentrations in the overlying waters to fall below 50 μmol L–1, the sediment porewater at all sites progressed through the expected anaerobic respiration sequence. The paucity of Fe and SO4 in the Australian lakes did not appear to constrain microbial iron and sulfate reduction. Indeed, the low Fe concentrations appeared to promote microbial sulfate reduction in the Australian sites. In the German site, there was little evidence of sulfide production in the porewater and no changes in porewater pH profiles. In contrast, the sediment porewater from the two Australian sites exhibited sulfide production and increased porewater pH. Bioremediation of acidic lakes must consider the need to treat iron-rich water before attempting pH amelioration.
GARP (LRRC32) is essential for the surface expression of latent TGF-β on platelets and activated FOXP3
+
regulatory T cells
Authors: Tran Dat Q. , Andersson John , Wang Rui , Ramsey Heather , Unutmaz Derya , Shevach Ethan M.
Published: July 2009

TGF-β family members are highly pleiotropic cytokines with diverse regulatory functions. TGF-β is normally found in the latent form associated with latency-associated peptide (LAP). This latent complex can associate with latent TGFβ-binding protein (LTBP) to produce a large latent form. Latent TGF-β is also found on the surface of activated FOXP3
+
regulatory T cells (Tregs), but it is unclear how it is anchored to the cell membrane. We show that GARP or LRRC32, a leucine-rich repeat molecule of unknown function, is critical for tethering TGF-β to the cell surface. We demonstrate that platelets and activated Tregs co-express latent TGF-β and GARP on their membranes. The knockdown of GARP mRNA with siRNA prevented surface latent TGF-β expression on activated Tregs and recombinant latent TGF-β1 is able to bind directly with GARP. Confocal microscopy and immunoprecipitation strongly support their interactions. The role of TGF-β on Tregs appears to have dual functions, both for Treg-mediated suppression and infectious tolerance mechanism.
Pleistocene desiccation in East Africa bottlenecked but did not extirpate the adaptive radiation of Lake Victoria haplochromine cichlid fishes
Authors: Elmer Kathryn R. , Reggio Chiara , Wirth Thierry , Verheyen Erik , Salzburger Walter , Meyer Axel
Published: July 2009

The Great Lakes region of East Africa, including Lake Victoria, is the center of diversity of the mega-diverse cichlid fishes (Perciformes: Teleostei). Paleolimnological evidence indicates dramatic desiccation of this lake ca. 18,000–15,000 years ago. Consequently, the hundreds of extant endemic haplochromine species in the lake must have either evolved since then or refugia must have existed, within that lake basin or elsewhere, from which Lake Victoria was recolonized. We studied the population history of the Lake Victoria region superflock (LVRS) of haplochromine cichlids based on nuclear genetic analysis (12 microsatellite loci from 400 haplochomines) of populations from Lake Kivu, Lake Victoria, and the connected and surrounding rivers and lakes. Population genetic analyses confirmed that Lake Kivu haplochromines colonized Lake Victoria. Coalescent analyses show a 30- to 50-fold decline in the haplochromine populations of Lake Victoria, Lake Kivu, and the region ca. 18,000–15,000 years ago. We suggest that this coincides with drastic climatic and geological changes in the late Pleistocene. The most recent common ancestor of the Lake Victoria region haplochromines was estimated to have existed about 4.5 million years ago, which corresponds to the first radiation of cichlids in Lake Tanganyika and the origin of the tribe Haplochrominii. This relatively old evolutionary origin may explain the high levels of polymorphism still found in modern haplochromines. This degree of polymorphism might have acted as a “genetic reservoir” that permitted the explosive radiation of hundreds of haplochromines and their array of contemporary adaptive morphologies.
Evidence for heteromorphic chromatin fibers from analysis of nucleosome interactions
Authors: Grigoryev Sergei A. , Arya Gaurav , Correll Sarah , Woodcock Christopher L. , Schlick Tamar
Published: July 2009

The architecture of the chromatin fiber, which determines DNA accessibility for transcription and other template-directed biological processes, remains unknown. Here we investigate the internal organization of the 30-nm chromatin fiber, combining Monte Carlo simulations of nucleosome chain folding with EM-assisted nucleosome interaction capture (EMANIC). We show that at physiological concentrations of monovalent ions, linker histones lead to a tight 2-start zigzag dominated by interactions between alternate nucleosomes (i ± 2) and sealed by histone N-tails. Divalent ions further compact the fiber by promoting bending in some linker DNAs and hence raising sequential nucleosome interactions (i ± 1). Remarkably, both straight and bent linker DNA conformations are retained in the fully compact chromatin fiber as inferred from both EMANIC and modeling. This conformational variability is energetically favorable as it helps accommodate DNA crossings within the fiber axis. Our results thus show that the 2-start zigzag topology and the type of linker DNA bending that defines solenoid models may be simultaneously present in a structurally heteromorphic chromatin fiber with uniform 30 nm diameter. Our data also suggest that dynamic linker DNA bending by linker histones and divalent cations in vivo may mediate the transition between tight nucleosome packing within discrete 30-nm fibers and self-associated higher-order chromosomal forms.
Production of
Clostridium difficile
toxin in a medium totally free of both animal and dairy proteins or digests
Authors: Fang Aiqi , Gerson Donald F. , Demain Arnold L.
Published: July 2009

In the hope of developing a vaccine against
Clostridium difficile
based on its toxin(s), we have developed a fermentation medium for the bacterium that results in the formation of Toxin A and contains no meat or dairy products, thus obviating the problem of possible prion diseases. Particular preparations of hydrolyzed soy proteins, especially Soy Peptone A3, have been found to replace both the meat/dairy product tryptone in the preparation of working cell banks and seed media, and NZ-Soy BL4 does the same in the fermentation medium. These replacements yield even higher toxin titers.
DNA-mediated redox signaling for transcriptional activation of SoxR
Authors: Lee Paul E. , Demple Bruce , Barton Jacqueline K.
Published: July 2009

In enteric bacteria, the cellular response to oxidative stress is activated by oxidation of the iron-sulfur clusters in SoxR, which then induces transcription of
soxS
, turning on a battery of defense genes. Here we demonstrate both in vitro and in cells that activation of SoxR can occur in a DNA-mediated reaction with guanine radicals, an early genomic signal of oxidative stress, serving as the oxidant. SoxR in its reduced form is found to inhibit guanine damage by repairing guanine radicals. Moreover, cells treated with a DNA-binding photooxidant, which generates guanine radicals, promotes the expression of
soxS
. In vitro, this photooxidant, tethered to DNA 80 bp from the
soxS
promoter, induces transcription by activating SoxR upon irradiation. Thus, transcription can be activated from a distance through DNA-mediated charge transport. This chemistry offers a general strategy for DNA-mediated signaling of oxidative stress.