bluuebunny/crossref_metadata_2025 huggingface dataset:
ORGANIZED SUPERSTRUCTURES AT NANOSCALE AND NEW FUNCTIONAL NANOMATERIALS
Authors: KISLOV V. , MEDVEDEV B. , GULYAEV YU. , TARANOV I. , KASHIN V. , KHOMUTOV G. , ARTEMIEV M. , GUREVICH S.
Published: November 2007

We report on a number of new effects of self-organization at nanoscale, leading to creation of new functional nanomaterials, including carbon and carbon–metal nanotoroids and nanodiscs and self-assembling of magnetic nanoparticles into helices and chains. We also extensively used a new approach of biopattern nanoengineering to create DNA-based complexes with metal or CdSe / ZnS core-shell nanorods (22 × 4.5 nm) which possess strong linearly polarized photoluminescence due to unidirectional orientation of nanorods along DNA filaments. Optical, electrical, and topological (geometrical) properties of such complexes were investigated. This work is a result of a coherent effort (since 1980s) of a consortium of Russian research groups in Nano-technology (INTC: Interdisciplinary Nanotechnology Consortium) aimed at creating molecular electronic devices based on individual and collective properties of specially designed and fabricated nanoclusters.
STM/STS STUDIES OF THE INITIAL STAGE OF GROWTH OF ULTRA-THIN Bi FILMS ON 7 × 7-Si(111) SURFACE
Authors: ORESHKIN A. I. , SADOWSKI J. T. , NAGAO T. , YAGINUMA S. , FUJIKAWA Y. , SAKURAI T. , SAITO M. , OHNO T.
Published: November 2007

The results of investigation of the room temperature growth of thin Bi films on Si (111)-7 × 7 are present. In the initial stage of Bi film growth the rotationally disordered, pseudo-cubic, Bi {012} islands with a uniform height of 13 Å are formed. With increasing bismuth on the surface, islands interconnect, maintaining however their uniform height, and structural phase transition of the {012} film into a hexagonal Bi (001) film takes place.
DIFFUSION LENGTH AND EFFECTIVE CARRIER LIFETIME IN III-NITRIDES
Authors: SHMIDT N. M. , TITKOV A. N. , YAKIMOV E. B.
Published: November 2007

The results of excess carrier diffusion length investigations in GaN and in the light emitting structures (LES) based on MQW InGaN / GaN with different ordering of mosaic structures are presented. It is confirmed that the diffusion length values in these structures indeed are essentially lower than 1 μm. The Electron Beam Induced Current investigations have shown that the effective diffusion length measured on GaN structures could be determined by the mosaic domain boundary effect on the excess carrier transport. Such nanosize domains could also determine the lateral localization in the MQW light emitting diodes. The mosaic structure ordering effect on the quantum efficiency of LES and high values of the effective carrier lifetime in well-ordered LES are discussed.
INVESTIGATIONS OF InGaN/GaN AND InGaN/InGaN QDS GROWN IN A WIDE PRESSURE MOCVD REACTOR
Authors: SIZOV D. S. , SIZOV V. S. , LUNDIN V. V. , ZAVARIN E. E. , TSATSUL'NIKOV A. F. , MUSIKHIN YU. G. , VLASOV A. S. , LEDENTSOV N. N. , MINTAIROV A. M. , SUN K. , MERZ J.
Published: November 2007

InGaN quantum dot (QD) formation in a wide pressure range MOCVD reactor was studied. The existence of QDs and their lateral size (2–5 nm) were demonstrated using transmission electron microscopy and high spatial resolution (~ 100 nm) near-field magneto-photoluminescence spectroscopy. We found that an increase of the reactor pressure from 400 to 1000 mbar leads to an order of magnitude increase in light emission efficiency of the InGaN / GaN QDs accompanied by ~ 100 meV redshift of the emission wavelength. We explored stimulated phase separation (SPS) to control carrier localization and emission wavelength. The SPS was achieved by adding In in the matrix material. This leads to formation of extremely deep InGaN / InGaN QDs having energy localization up to ~ 0.8 eV, which was revealed from selectively excited far-field photoluminescence (PL) spectra. Without SPS the QD activation energy is found to be below 0.2 eV. A nonequilibrium carrier population strongly suppresses the temperature-induced shift of the PL emission in deep InGaN QDs.
Phospholamban knockout increases CaM kinase II activity and intracellular Ca2+wave activity and alters contractile responses of murine gastric antrum
Authors: Kim Minkyung , Hennig Grant W. , Smith Terence K. , Perrino Brian A.
Published: November 2007

Phospholamban (PLB) inhibits the sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA), and this inhibition is relieved by Ca2+calmodulin-dependent protein kinase II (CaM kinase II) phosphorylation. We previously reported significant differences in contractility, SR Ca2+release, and CaM kinase II activity in gastric fundus smooth muscles as a result of PLB phosphorylation by CaM kinase II. In this study, we used PLB-knockout (PLB-KO) mice to directly examine the effect of PLB absence on contractility, CaM kinase II activity, and intracellular Ca2+waves in gastric antrum smooth muscles. The frequencies and amplitudes of spontaneous phasic contractions were elevated in antrum smooth muscle strips from PLB-KO mice. Bethanecol increased the amplitudes of phasic contractions in antrum smooth muscles from both control and PLB-KO mice. Caffeine decreased and cyclopiazonic acid (CPA) increased the basal tone of antrum smooth muscle strips from PLB-KO mice, but the effects were less pronounced compared with control strips. The CaM kinase II inhibitor KN-93 was less effective at inhibiting caffeine-induced relaxation in antrum smooth muscle strips from PLB-KO mice. CaM kinase II autonomous activity was elevated, and not further increased by caffeine, in antrum smooth muscles from PLB-KO mice. Similarly, the intracellular Ca2+wave frequency was elevated, and not further increased by caffeine, in antrum smooth muscles from PLB-KO mice. These findings suggest that PLB is an important modulator of gastric antrum smooth muscle contractility by modulation of SR Ca2+release and CaM kinase II activity.
Lymphocytic microparticles inhibit angiogenesis by stimulating oxidative stress and negatively regulating VEGF-induced pathways
Authors: Yang Chun , Mwaikambo Bupe R. , Zhu Tang , Gagnon Carmen , Lafleur Josiane , Seshadri Swathi , Lachapelle Pierre , Lavoie Jean-Claude , Chemtob Sylvain , Hardy Pierre
Published: November 2007

Recent studies have demonstrated that lymphocyte-derived microparticles (LMPs) impair endothelial cell function. However, no data currently exist regarding the contribution of LMPs in the regulation of angiogenesis. In the present study, we investigated the effects of LMPs on angiogenesis in vivo and in vitro and demonstrated that LMPs strongly suppressed aortic ring microvessel sprouting and in vivo corneal neovascularization. In vitro, LMPs considerably diminished human umbilical vein endothelial cell survival and proliferation in a concentration-dependent manner. Mechanistically, the antioxidants U-74389G and U-83836E were partially protective against the antiproliferative effects of LMPs, whereas the NADPH oxidase (NOX) inhibitors apocynin and diphenyleneiodonium significantly abrogated these effects. Moreover, LMPs increased not only the expression of the NOX subunits gp91phox, p22phox, and p47phox, but also the production of ROS and NOX-derived superoxide (O2−). Importantly, LMPs caused a pronounced augmentation in the protein expression of the CD36 antiangiogenic receptor while significantly downregulating the protein levels of VEGF receptor type 2 and its downstream signaling mediator, phosphorylated ERK1/2. In summary, LMPs potently suppress neovascularization in vivo and in vitro by augmenting ROS generation via NOX and interfering with the VEGF signaling pathway.
Endothelial nitric oxide synthase is predominantly involved in angiotensin II modulation of renal vascular resistance and norepinephrine release
Authors: Stegbauer Johannes , Kuczka Yvonne , Vonend Oliver , Quack Ivo , Sellin Lorenz , Patzak Andreas , Steege Andreas , Langnaese Kristina , Rump Lars Christian
Published: November 2007

Nitric oxide (NO) is mainly generated by endothelial NO synthase (eNOS) or neuronal NOS (nNOS). Recent studies indicate that angiotensin II generates NO release, which modulates renal vascular resistance and sympathetic neurotransmission. Experiments in wild-type [eNOS(+/+) and nNOS(+/+)], eNOS-deficient [eNOS(−/−)], and nNOS-deficient [nNOS(−/−)] mice were performed to determine which NOS isoform is involved. Isolated mice kidneys were perfused with Krebs-Henseleit solution. Endogenous norepinephrine release was measured by HPLC. Angiotensin II dose dependently increased renal vascular resistance in all mice species. EC50and maximal pressor responses to angiotensin II were greater in eNOS(−/−) than in nNOS(−/−) and smaller in wild-type mice. The nonselective NOS inhibitor Nω-nitro-l-arginine methyl ester (l-NAME; 0.3 mM) enhanced angiotensin II-induced pressor responses in nNOS(−/−) and wild-type mice but not in eNOS(−/−) mice. In nNOS(+/+) mice, 7-nitroindazole monosodium salt (7-NINA; 0.3 mM), a selective nNOS inhibitor, enhanced angiotensin II-induced pressor responses slightly. Angiotensin II-enhanced renal nerve stimulation induced norepinephrine release in all species. l-NAME (0.3 mM) reduced angiotensin II-mediated facilitation of norepinephrine release in nNOS(−/−) and wild-type mice but not in eNOS(−/−) mice. 7-NINA failed to modulate norepinephrine release in nNOS(+/+) mice. (4-Chlorophrnylthio)guanosine-3′, 5′-cyclic monophosphate (0.1 nM) increased norepinephrine release. mRNA expression of eNOS, nNOS, and inducible NOS did not differ between mice strains. In conclusion, angiotensin II-mediated effects on renal vascular resistance and sympathetic neurotransmission are modulated by NO in mice. These effects are mediated by eNOS and nNOS, but NO derived from eNOS dominates. Only NO derived from eNOS seems to modulate angiotensin II-mediated renal norepinephrine release.
Dynamic left ventricular elastance: a model for integrating cardiac muscle contraction into ventricular pressure-volume relationships
Authors: Campbell Kenneth B. , Simpson Amy M. , Campbell Stuart G. , Granzier Henk L. , Slinker Bryan K.
Published: November 2007

To integrate myocardial contractile processes into left ventricular (LV) function, a mathematical model was built. Muscle fiber force was set equal to the product of stiffness and elastic distortion of stiffness elements, i.e., force-bearing cross bridges (XB). Stiffness dynamics arose from recruitment of XB according to the kinetics of myofilament activation and fiber-length changes. Elastic distortion dynamics arose from XB cycling and the rate-of-change of fiber length. Muscle fiber stiffness and distortion dynamics were transformed into LV chamber elastance and volumetric distortion dynamics. LV pressure equaled the product of chamber elastance and volumetric distortion, just as muscle-fiber force equaled the product of muscle-fiber stiffness and lineal elastic distortion. Model validation was in terms of its ability to reproduce cycle-time-dependent LV pressure response, ΔP( t), to incremental step-like volume changes, ΔV, in the isolated rat heart. All ΔP( t), regardless of the time in the cycle at which ΔP( t) was elicited, consisted of three phases: phase 1, concurrent with the leading edge of ΔV; phase 2, a brief transient recovery from phase 1; and phase 3, sustained for the duration of systole. Each phase varied with the time in the cycle at which ΔP( t) was elicited. When the model was fit to the data, cooperative activation was required to sustain systole for longer periods than was possible with Ca2+ activation alone. The model successfully reproduced all major features of the measured ΔP( t) responses, and thus serves as a credible indicator of the role of underlying contractile processes in LV function.
Efficient Tracking of the Dominant Eigenspace of a Normalized Kernel Matrix
Authors: Gins Geert , Smets Ilse Y. , Van Impe Jan F.
Published: November 2007

Various machine learning problems rely on kernel-based methods. The power of these methods resides in the ability to solve highly nonlinear problems by reformulating them in a linear context. The dominant eigenspace of a (normalized) kernel matrix is often required. Unfortunately, the computational requirements of the existing kernel methods are such that the applicability is restricted to relatively small data sets. This letter therefore focuses on a kernel-based method for large data sets. More specifically, a numerically stable tracking algorithm for the dominant eigenspace of a normalized kernel matrix is proposed, which proceeds by an updating (the addition of a new data point) followed by a downdating (the exclusion of an old data point) of the kernel matrix. Testing the algorithm on some representative case studies reveals that a very good approximation of the dominant eigenspace is obtained, while only a minimal amount of operations and memory space per iteration step is required.
Design of Continuous Attractor Networks with Monotonic Tuning Using a Symmetry Principle
Authors: Machens Christian K. , Brody Carlos D.
Published: November 2007

Neurons that sustain elevated firing in the absence of stimuli have been found in many neural systems. In graded persistent activity, neurons can sustain firing at many levels, suggesting a widely found type of network dynamics in which networks can relax to any one of a continuum of stationary states. The reproduction of these findings in model networks of nonlinear neurons has turned out to be nontrivial. A particularly insightful model has been the “bump attractor,” in which a continuous attractor emerges through an underlying symmetry in the network connectivity matrix. This model, however, cannot account for data in which the persistent firing of neurons is a monotonic—rather than a bell-shaped—function of a stored variable. Here, we show that the symmetry used in the bump attractor network can be employed to create a whole family of continuous attractor networks, including those with monotonic tuning. Our design is based on tuning the external inputs to networks that have a connectivity matrix with Toeplitz symmetry. In particular, we provide a complete analytical solution of a line attractor network with monotonic tuning and show that for many other networks, the numerical tuning of synaptic weights reduces to the computation of a single parameter.
A-Type K+ Current Can Act as a Trigger for Bursting in the Absence of a Slow Variable
Authors: Toporikova Natalia , Tabak Joël , Freeman Marc E. , Bertram Richard
Published: November 2007

Models of bursting in single cells typically include two subsystems with different timescales. Variations in one or more slow variables switch the system between a silent and a spiking state. We have developed a model for bursting in the pituitary lactotroph that does not include any slow variable. The model incorporates fast, noninactivating calcium and potassium currents (the spike-generating mechanism), as well as the fast, inactivating A-type potassium current (IA). IA is active only briefly at the beginning of a burst, but this brief impulse of IA acts as a burst trigger, injecting the spike trajectory close to an unstable steady state. The spiraling of the trajectory away from the steady state produces a period of low-amplitude spiking typical of lactotrophs. Increasing the conductance of A-type potassium current brings the trajectory closer to the unstable steady state, increasing burst duration. However, this also increases interburst interval, and for larger conductance values, all activity stops. To our knowledge, this is the first example of a physiologically based, single-compartmental model of bursting with no slow subsystem.
Brain Reading Using Full Brain Support Vector Machines for Object Recognition: There Is No “Face” Identification Area
Authors: Hanson Stephen José , Halchenko Yaroslav O.
Published: November 2007

Over the past decade, object recognition work has confounded voxel response detection with potential voxel class identification. Consequently, the claim that there are areas of the brain that are necessary and sufficient for object identification cannot be resolved with existing associative methods (e.g., the general linear model) that are dominant in brain imaging methods. In order to explore this controversy we trained full brain (40,000 voxels) single TR (repetition time) classifiers on data from 10 subjects in two different recognition tasks on the most controversial classes of stimuli (house and face) and show 97.4% median out-of-sample (unseen TRs) generalization. This performance allowed us to reliably and uniquely assay the classifier's voxel diagnosticity in all individual subjects' brains. In this two-class case, there may be specific areas diagnostic for house stimuli (e.g., LO) or for face stimuli (e.g., STS); however, in contrast to the detection results common in this literature, neither the fusiform face area nor parahippocampal place area is shown to be uniquely diagnostic for faces or places, respectively.
Bishop Alfred Tucker and the Establishment of a British Protectorate in Uganda 1890-94
Authors: Griffiths Tudor
Published: November 2007

The article considers the involvement of Bishop Alfred Tucker and other missionaries of the Church Missionary Society (CMS) in the establishment of a British Protectorate in Buganda between 1890 and 1894. These missionaries were drawn, often not unwillingly, into political affairs, both within Uganda and internationally. The contribution made by Tucker was frequently ill-informed and sometimes tendentious. Nevertheless, he sought to uphold the long-standing CMS regulation that missionaries should abstain from any political involvement. The theoretical distinction between the sacred and secular was alien to the intellectual heritage of Uganda, and in practice it was contradicted by the activities of CMS missionaries, who justified their involvement in terms of considering Uganda to be a 'special case'.
The Reconstruction of Imperial Mathematics in China During the Kangxi Reign (1662-1722)
Authors:   Han Qi, Jami Catherine
Published: November 2007

Contrary to astronomy, the early modern Chinese State did not systematically sponsor mathematics. However, early in his reign, the Kangxi Emperor studied this subject with the Jesuit missionaries in charge of the calendar. His first teacher, Ferdinand Verbiest (1623-1688) relied on textbooks based on Christoph Clavius' (1538-1612). Those who succeeded Verbiest as imperial tutors in the 1690s produced lecture notes in Manchu and Chinese. Newly discovered manuscripts show Antoine Thomas (1644-1709) wrote substantial treatises on arithmetic and algebra while teaching those subjects. In 1713, the emperor commissioned a group of scholars and officials to compile a standard survey of mathematics (Shuli jingyun, "Essential principles of mathematics"). This work opened with the claim that mathematics had its roots in Chinese Antiquity. However, it can be shown that the Jesuits' lecture notes were the main source of the Shuli jingyun. The reconstruction of mathematics under Kangxi's patronage is thus best characterised as the imperial appropriation of Western learning.
Caligula, the Church of Antioch and the Gentile Mission
Authors: Taylor Nicholas H.
Published: November 2007

This study examines such data as are available regarding the impact of the crisis which confronted Jewish communities in many parts of the Roman Empire during the reign of Gaius Caligula (37-41 CE). Particular attention is given to Antioch on the Orontes, and to the Christian community which emerged there and was to become a major force both in the spread of Christianity and in the conversion of Gentiles to a hitherto Jewish movement. It is argued that the crisis was a major catalyst in changing the character of the Christian church in Antioch, so that it acquired an identity distinct from that of the Jewish community. The reappraisal of eschatological expectations occasioned by the crisis led to the conviction that Gentiles must be included in the Church before the parousia of Christ.
Human Rights in the Name of God?
Authors: Pieterse Hendrik J.C. , Van Der Ven Johannes A. , Dreyer Jaco S.
Published: November 2007

This article is a study of the tension which arises because South Africa is a religious society within a secular state, or a secular state embedded in a religious society. The belief in God among Grade 11 students in the Johannesburg/ Pretoria region is investigated, and questions are posed as to the role belief in God plays in the formation of their attitudes towards human rights. Fundamental aspects of the relationship between belief in God and human rights are dealt with, students' belief in God is investigated and described, and finally, it is asked whether the students believe that there is a God of human rights.
Heretic But Faithful: the Reclamation of the Body as Sacred in Christian Feminist Theology
Authors: Van Schalkwyk Annalet
Published: November 2007

This article investigates the history of Christian patriarchy, misogyny and devaluation of the body, and the response of the feminist theological movement to this history; namely to reclaim the (female) body as sacred. It uses a metaphorical method to rediscover the goddess traditions as one of the main sources for such are-appraisal of the body as sacred. This is done because, in these ancient traditions, the female (and male) body was regarded as sacred, powerful and fruitful and the sexuality of the human body was accepted fully. The author then continues to investigate how three contemporary feminist theologians use this metaphorical approach and combine it with historical, psychological and exegetical approaches to rediscover and re-evaluate the sacredness and the goodness of the (female) body. By doing so, the author also assesses these theologians' understanding of Eros as that primordial life-force in the lives of women and men which include the spiritual-psychological, the physical, the erotic, the rational as well as the political. In short, these theologians have a basic understanding of Eros as love and power in action.
South African New Age Prophets: Past and Present
Authors: Steyn H. Christina
Published: November 2007

This article explores the visions, beliefs and prophecies of three remarkable South Africans. Johanna Brandt, Jan Smuts, and Joseph Busby espoused ideas that are central to New Age thought today. All three may be seen as Prophets': Brandt as the messenger of God who receives visions and is compelled to proclaim it to the nation; Smuts as the visionary with remarkable insight into the nature of reality; and Busby as the mouthpiece of an Ascended Master of the Spiritual Hierarchy who conveys important messages to the South African people. Brandt and Smuts were ahead of their time and their work was not at all well received by the local community. Brandt was eventually censored by her church and although Smuts was honoured in many circles for his statesmanship, his scientific theories with their metaphysical implications were spurned in this country. Busby, on the other hand, was not a particularly well-known person outside New Age circles, but he had a following among whom his work was welcomed and honoured. From this short review, it is clear that the central concepts of New Age philosophy have been taught in South Africa for many years and today it has penetrated the minds and beliefs of many South Africans.
Creation and Re-Creation: the Origins and Preservation of the Shinto Shrines At Ise, Japan, and the Abbey Church of St. Michael At Hildesheim, Germany
Authors: Maré Estelle A.
Published: November 2007

In this article Ise Jingu, Japan, and the church of St Michael, Germany, are juxtaposed. At first glance they do not seem to have much in common, except that they exist as a testimony to the intentions of the original builders who established their distinctive architectural traditions and, physically, both are recent reconstructions. The reasons for their reconstruction are different because, whereas the Ise precincts are renewed as it were in obedience to a sacred injunction at a place where war never occurred, the renewal of the Hildesheim church to its original design is predominantly the result of circumstance and the vicissitudes of devastation, plunder and war.
Assimilation of Satellite Cloud Data into the GMAO Finite-Volume Data Assimilation System Using a Parameter Estimation Method. Part I: Motivation and Algorithm Description
Authors: Norris Peter M. , da Silva Arlindo M.
Published: November 2007

General circulation models are unable to resolve subgrid-scale moisture variability and associated cloudiness and so must parameterize grid-scale cloud properties. This typically involves various empirical assumptions and a failure to capture the full range (synoptic, geographic, diurnal) of the subgrid-scale variability. A variational parameter estimation technique is employed to adjust empirical model cloud parameters in both space and time, in order to better represent assimilated International Satellite Cloud Climatology Project (ISCCP) cloud fraction and optical depth and Special Sensor Microwave Imager (SSM/I) liquid water path. The value of these adjustments is verified by much improved cloud radiative forcing and persistent improvement in cloud fraction forecasts.
A Fast Cloud Overlap Parameterization for Microwave Radiance Assimilation
Authors: O’Dell Christopher W. , Bauer Peter , Bennartz Ralf
Published: November 2007

The assimilation of cloud- and rain-affected radiances in numerical weather prediction systems requires fast and accurate radiative transfer models. One of the largest sources of modeling errors originates from the assumptions regarding the vertical and horizontal subgrid-scale variability of model clouds and precipitation. In this work, cloud overlap assumptions are examined in the context of microwave radiative transfer and used to develop an accurate reference model. A fast cloud overlap algorithm is presented that allows for the accurate simulation of microwave radiances with a small number of radiative transfer calculations. In particular, the errors for a typical two-column approach currently used operationally are found to be relatively large for many cases of cloudy fields containing precipitation, even those with an overall cloud fraction of unity; these errors are largely eliminated by using the new approach presented here, at the cost of a slight increase in computation time. Radiative transfer cloud overlap errors are also evident in simulations when compared to actual satellite observations, in that the biases are somewhat reduced when applying a more accurate treatment of cloud overlap.
The Remote Sensing of Clouds and Precipitation from Space: A Review
Authors: Stephens Graeme L. , Kummerow Christian D.
Published: November 2007

This paper presents a critical review of a number of popular methods that have been developed to retrieve cloud and precipitation properties from satellite radiance measurements. The emphasis of the paper is on the retrieval uncertainties associated with these methods, as these shape future data assimilation applications, either in the form of direct radiance assimilation or assimilation of retrieved geophysical data, or even in the use of retrieved information as a source of model error characterization. It is demonstrated throughout the paper how cloud and precipitation observing systems developed around seemingly simple concepts are in fact very complex and largely underconstrained, which explains, in part, why assigning realistic errors to these properties has been so elusive in the past. Two primary sources of error that define the observing system are highlighted throughout: (i) the first source is errors associated with the identification of cloudy scenes from clear scenes and the identification of precipitation in cloudy scenes from nonprecipitating cloudy scenes. The problems of discriminating of cloud clear and cloud precipitation are illustrated using examples drawn from microwave cloud liquid water path and precipitation retrievals. (ii) The second source is errors introduced by the forward model and its related parameters. The forward model generally contains two main components: a model of the atmosphere and the cloud and precipitation structures imbedded in that atmosphere and a forward model of the radiative transfer that produces the synthetic measurement that is ultimately compared to the measurement. The vast majority of methods developed for deriving cloud and precipitation information from satellite measurements is highly sensitive to these model parameters, which merely reflects the underconstrained nature of the problem and the need for other information in deriving solutions. The cloud and precipitation retrieval examples presented in this paper are most often constructed around very unrealistic atmosphere models typically composed of just a few layers. The consequence is that the retrievals become too sensitive to the unobserved parameters of those layers and the atmosphere above and below. Clearly a better definition of the atmospheric state, and the vertical structure of clouds and precipitation, are needed to improve the information extracted from satellite observations, and it is for this reason that the combination of active and passive measurements offers much hope for improving cloud and precipitation retrievals.
Dynamics of Convectively Driven Banded Jets in the Laboratory
Authors: Read Peter L. , Yamazaki Yasuhiro H. , Lewis Stephen R. , Williams Paul D. , Wordsworth Robin , Miki-Yamazaki Kuniko , Sommeria Joël , Didelle Henri
Published: November 2007

The banded organization of clouds and zonal winds in the atmospheres of the outer planets has long fascinated observers. Several recent studies in the theory and idealized modeling of geostrophic turbulence have suggested possible explanations for the emergence of such organized patterns, typically involving highly anisotropic exchanges of kinetic energy and vorticity within the dissipationless inertial ranges of turbulent flows dominated (at least at large scales) by ensembles of propagating Rossby waves. The results from an attempt to reproduce such conditions in the laboratory are presented here. Achievement of a distinct inertial range turns out to require an experiment on the largest feasible scale. Deep, rotating convection on small horizontal scales was induced by gently and continuously spraying dense, salty water onto the free surface of the 13-m-diameter cylindrical tank on the Coriolis platform in Grenoble, France. A “planetary vorticity gradient” or “β effect” was obtained by use of a conically sloping bottom and the whole tank rotated at angular speeds up to 0.15 rad s−1. Over a period of several hours, a highly barotropic, zonally banded large-scale flow pattern was seen to emerge with up to 5–6 narrow, alternating, zonally aligned jets across the tank, indicating the development of an anisotropic field of geostrophic turbulence. Using particle image velocimetry (PIV) techniques, zonal jets are shown to have arisen from nonlinear interactions between barotropic eddies on a scale comparable to either a Rhines or “frictional” wavelength, which scales roughly as (β/Urms)−1/2. This resulted in an anisotropic kinetic energy spectrum with a significantly steeper slope with wavenumber k for the zonal flow than for the nonzonal eddies, which largely follows the classical Kolmogorov k−5/3 inertial range. Potential vorticity fields show evidence of Rossby wave breaking and the presence of a “hyperstaircase” with radius, indicating instantaneous flows that are supercritical with respect to the Rayleigh–Kuo instability criterion and in a state of “barotropic adjustment.” The implications of these results are discussed in light of zonal jets observed in planetary atmospheres and, most recently, in the terrestrial oceans.
A Total Turbulent Energy Closure Model for Neutrally and Stably Stratified Atmospheric Boundary Layers
Authors: Mauritsen Thorsten , Svensson Gunilla , Zilitinkevich Sergej S. , Esau Igor , Enger Leif , Grisogono Branko
Published: November 2007

This paper presents a turbulence closure for neutral and stratified atmospheric conditions. The closure is based on the concept of the total turbulent energy. The total turbulent energy is the sum of the turbulent kinetic energy and turbulent potential energy, which is proportional to the potential temperature variance. The closure uses recent observational findings to take into account the mean flow stability. These observations indicate that turbulent transfer of heat and momentum behaves differently under very stable stratification. Whereas the turbulent heat flux tends toward zero beyond a certain stability limit, the turbulent stress stays finite. The suggested scheme avoids the problem of self-correlation. The latter is an improvement over the widely used Monin–Obukhov-based closures. Numerous large-eddy simulations, including a wide range of neutral and stably stratified cases, are used to estimate likely values of two free constants. In a benchmark case the new turbulence closure performs indistinguishably from independent large-eddy simulations.
Assimilation of Satellite Cloud and Precipitation Observations in Numerical Weather Prediction Models: Introduction to the JAS Special Collection
Authors: Errico Ronald M. , Ohring George , Weng Fuzhong , Bauer Peter , Ferrier Brad , Mahfouf Jean-François , Turk Joe
Published: November 2007

To date, the assimilation of satellite measurements in numerical weather prediction (NWP) models has focused on the clear atmosphere. But satellite observations in the visible, infrared, and microwave provide a great deal of information on clouds and precipitation. This special collection describes how to use this information to initialize clouds and precipitation in models. Since clouds and precipitation often occur in sensitive regions for forecast impacts, such improvements are likely necessary for continuing to acquire significant gains in weather forecasting.

This special collection of the Journal of the Atmospheric Sciences is devoted to articles based on papers presented at the International Workshop on Assimilation of Satellite Cloud and Precipitation Observations in Numerical Weather Prediction Models, in Lansdowne, Virginia, in May 2005. This introduction summarizes the findings of the workshop. The special collection includes review articles on satellite observations of clouds and precipitation (Stephens and Kummerow), parameterizations of clouds and precipitation in NWP models (Lopez), radiative transfer in cloudy/precipitating atmospheres (Weng), and assimilation of cloud and precipitation observations (Errico et al.), as well as research papers on these topics.
Political skill and influence effectiveness: Testing portions of an expanded Ferris and Judge (1991) model
Authors: Kolodinsky Robert W. , Treadway Darren C. , Ferris Gerald R.
Published: November 2007

The present study tested por tions of an expanded Ferris and Judge (1991) framework regarding influence processes in human resources decisions and actions. In particular, the roles of political skill and a particularly efficacious influence tactic, rationality, were examined with respect to their interactive effects on supervisor perceptions and evaluations. Online questionnaires were used to collect data from full-time, non-faculty employees of a large south-eastern US public university. To avoid problems associated with common method variance resulting from same source data, supervisors rated subordinates on outcome measures and subordinates supplied data on predictors. The final sample was comprised of a matched dyadic data set of 291 subordinates and their supervisors. Results indicated support for the hypotheses. Specifically, political skill was found to directly relate to the use of rationality and moderate the positive relationship between rationality and two supervisory perceptions known to affect supervisor ratings of job performance, notably supervisor liking of subordinates and perceived similarity to subordinates. Further, perceptions of liking and similarity were positively related to supervisor ratings of both task performance and two important contextual job performance components. Implications of the results, strengths and limitations of the research, and directions for future research are discussed.
Microstructure and Mechanical Properties of Ti—48A1—2Nb—2Cr Matrix High Temperature Self-Lubricating Composites by Addition of 38%CaF2—62%BaF2 Eutectic Solid Lubricants
Authors: Liying Yang , Zuomin Liu
Published: November 2007

Tribological properties and mechanical strengths of high temperature self-lubrication composites must be considered fully. Sometimes addition of solid lubricants result in the mechanical properties degradation of the composites at room temperature. In this article, the microstructure and mechanical properties of Ti—48Al—2Nb—2Cr composites with addition of different weight contents of 38%CaF2—62%BaF2 eutectic solid lubricant were evaluated. It is indicated that pores or cavities are mostly concentrated in solid lubricant and in chromium, niobium aluminide. The bending strength and fracture toughness of Ti— 48Al—2Nb—2Cr composites with 0—5 wt% solid lubricant were enhanced significantly. The strengthening mechanism is due to solid solution hardening and increase of dislocation motion. However, when additions of lubricant content exceed 5wt%, increase of porosity and cracks result in the decreases of mechanical properties.
Optimization of the Dynamic Characteristics of Composite Plates Using an Inverse Approach
Authors: Mirzaeifar R. , Bahai H. , Aryana F. , Yeilaghi A.
Published: November 2007

This article presents an inverse formulation of the eigenvalue problem for computing the required changes in laminated composite plates in order to achieve desired dynamic characteristics in the structure. The stiffness and mass matrices of the plated structure are first derived using the finite element formulation based on the first-order shear deformation theory (FSDT) for laminated composite plates with arbitrary angle-ply stacking sequence. Based on this formulation and using the first- and second-order Taylor expansion both the direct and inverse eigenvalue problems are formulated to find the changes in eigenvalues due to an arbitrary change in physical or geometrical properties of the structure. An initial sensitivity analysis is conducted to identify the layer in which modification of design variables have the most influence on the structures dynamic characteristics. The design variables in this context are defined as the fiber angles in each layer and the layer thickness. The proposed algorithm is applied to several case studies to demonstrate the application and the accuracy of the proposed formulation in solving the direct and the inverse eigenvalue problems with one and two design variables. Dynamic behavior modification of a plate is performed using the inverse approach, and the required modified stacking sequence is obtained to shift the natural frequencies to desired values.
A Randomized, Placebo‐Controlled Trial to Evaluate the Efficacy, Safety, and Pharmacodynamic Interaction of Coadministered Amlodipine and Atorvastatin in 1660 Patients With Concomitant Hypertension and Dyslipidemia: The Respond Trial
Authors: Preston Richar A. , Harvey Peter , Herfert Ottmar , Dykstra Gary , Jukema J. Wouter , Sun Franklin , Gillen David
Published: November 2007

Guidelines stress the importance of the simultaneous management of multiple cardiovascular risk factors. This can in part be achieved by coadministration of lipid‐lowering and antihypertensive treatments. Potential pharmacodynamic interaction between drugs should be investigated as part of developing single‐pill combinations. The Respond trial assessed whether combining amlodipine to treat hypertension and atorvastatin to treat dyslipidemia affected the action of either monotherapy. A total of 1660 hypertensive patients with dyslipidemia received 1 of 15 combinations of amlodipine (placebo, 5, or 10 mg) and atorvastatin (placebo, 10, 20, 40, or 80 mg) in a 3 × 5 factorial randomized, placebo‐controlled design. At 8 weeks, combination‐treated patients experienced dose‐related and statistically significant reductions in systolic blood pressure, low‐density lipoprotein cholesterol, and Framingham risk score. Overall, coadministered atorvastatin and amlodipine was well tolerated and without adverse pharmacodynamic interaction; combination treatment did not affect the low‐density lipoprotein cholesterol‐lowering efficacy and safety of atorvastatin, or the systolic blood pressure‐lowering efficacy and safety of amlodipine.
Bearing More Risk for Results
Authors: Benjamin Lehn M.
Published: November 2007

Performance accountability systems require nonprofits to bear more risk for achieving results. Although a growing body of work has examined nonprofit accountability, less attention has been given to the concept of risk. This article points to a potential conflict between performance accountability frameworks and nonprofit work. This conflict can be best understood as a one between managing risk in task-driven relationships, in which relationships are formed simply to achieve desirable results, and managing risk in developmentally driven relationships, in which performing a task is intended not only to achieve desirable results but also to build enduring capacity to take action on common problems.
Advances in Occupational Health: From a Stressful Beginning to a Positive Future †
Authors: Macik-Frey Marilyn , Quick James Campbell , Nelson Debra L.
Published: November 2007

The authors briefly review the literature on occupational health, including occupational medicine, occupational health psychology, and occupational safety, framing the current convergence of these from their scientific origins in preventive medicine and its most basic science of epidemiology, in psychology, and in engineering. They give attention to the burden of suffering, which concerns issues of morbidity and mortality within a population group, and consider both the economic and humanitarian perspectives of the burden of suffering, which may occur within a working population as a result of poor occupational health. The authors see reason for optimism for the future and identify two sets of emerging trends: one set that includes four positive advances—positive health, leadership, mood and emotions, and interventions—and one that falls under the authors' rubric of new horizons—technology, virtual work, globalization, and aging. The authors conclude with attention to zest at work, along with cardiovascular health and well-being.
Taking a Multifoci Approach to the Study of Justice, Social Exchange, and Citizenship Behavior: The Target Similarity Model†
Authors: Lavelle James J. , Rupp Deborah E. , Brockner Joel
Published: November 2007

An emerging trend within the organizational justice, social exchange, and organizational citizenship behavior literatures is that employees maintain distinct perceptions about, and direct different attitudes and behaviors toward, multiple foci such as the organization, supervisors, and coworkers. However, these multifoci developments have progressed, for the most part, independently of one another. Thus, to gain a more complete conceptualization of the employee experience, this review brings these respective literatures together. Specifically, the authors (a) review and organize multifoci research and theory in justice, social exchange, and citizenship behavior, (b) develop a “target similarity” model to provide a theoretical framework for conceptualizing and integrating multifoci research, and (c) o fer suggestions for future multifoci research.
A Cross-Disciplinary Exploration of Entrepreneurship Research
Authors: Duane Ireland R. , Webb Justin W.
Published: November 2007

The eclectic and pervasive benefits of entrepreneurship are generating research questions that interest scholars in a variety of disciplines. These questions have been primarily examined within the context of a scholar's home discipline while ignoring insights from other disciplines. This approach has left entrepreneurship research as a widely dispersed, loosely connected domain of issues. In this review, the authors explore entrepreneurship research in accounting, anthropology, economics, finance, management, marketing, operations management, political science, psychology, and sociology. They seek to identify common interests that can serve as a bridge for scholars interested in using a multitheoretic and multimethodological lens to design and complete entrepreneurship studies.
The Effects of Team Diversity on Team Outcomes: A Meta-Analytic Review of Team Demography
Authors: Horwitz Sujin K. , Horwitz Irwin B.
Published: November 2007

Over the past few decades, a great deal of research has been conducted to examine the complex relationship between team diversity and team outcomes. However, the impact of team diversity on team outcomes and moderating variables potentially affecting this relationship are still not fully answered with mixed findings in the literature. These research issues were, therefore, addressed by quantitatively reviewing extant work and provided estimates of the relationship between team diversity and team outcomes. In particular, the effects of task-related and bio-demographic diversity at the group-level were meta-analyzed to test the hypothesis of synergistic performance resulting from diverse employee teams. Support was found for the positive impact of task-related diversity on team performance although bio-demographic diversity was not significantly related to team performance. Similarly, no discernible effect of team diversity was found on social integration. The implications of the review for future research and practices are also discussed.
Classic Text No. 72 Non-dementia non-praecox: note on the advantages to mental hygiene of extirpating a term
Authors: Southard E.E. , Noll Richard
Published: November 2007

In February 1919 the Harvard neuropathologist Elmer Ernst Southard (1876—1920) presented a paper in which he outlined his reasons for dropping the term `dementia praecox' in favour of a competing diagnostic concept and term, `schizophrenia'. Southard's criticisms reflected the opinion of many US psychiatrists at that time, leading to the replacement of Emil Kraepelin's dementia praecox by Eugen Bleuler's schizophrenia in US psychiatry by the mid-1920s. The text of Southard's lecture is published here for the first time. Also included are excerpts from letters from US psychiatrists George H. Kirby, Albert M. Barrett, Adolf Meyer and August Hoch to Southard in response to his query as to whether dementia praecox or schizophrenia should be adopted in US psychiatric nomenclature.
Stochastic Frontier Analysis of Hospital Inefficiency
Authors: Rosko Michael D. , Mutter Ryan L.
Published: November 2007

Twenty stochastic frontier analysis (SFA) studies of hospital inefficiency in the United States were analyzed. Results from best-practice methods were compared against previously used methods in hospital studies to ascertain the robustness of SFA in estimating cost inefficiency. To compare past studies and analyze new data, SFA methods were varied by (a) the assumptions of the structure of costs and distribution of the error term, (b) inclusion of quality and product descriptor measures, and (c) use of simultaneous and two-stage estimation techniques. SFA results were relatively insensitive to several model variations.
Indirect Industry-and Subindustry-Level Managerial Discretion Measurement
Authors: Keegan Jack , Kabanoff Boris
Published: November 2007

Hambrick and Finkelstein's managerial discretion model has received limited research attention, partly because managerial discretion is difficult to operationalize. Abrahamson and Hambrick measured attentional homogeneity, ``the degree of similarity of foci of attention of managers in an industry,'' and demonstrated that it is strongly and negatively correlated with industry-level discretion (ILD). The authors measure attentional homogeneity more accurately and elegantly and show that attentional heterogeneity, the negative of attentional homogeneity, is a viable operationalization of ILD. They extend the technique and measure average levels of managerial discretion for subindustry groups and, using debt discipline as their example, demonstrate the contextual effects of ILD and show that discretion determinants can have nonlinear interactions.