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Upper Levels (upper + level)
Selected AbstractsCorrecting poor vitamin D status: Do older adults need higher repletion doses of vitamin D3 than younger adults?MOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 8 2010Susan J. Whiting Abstract We conducted an examination of recent studies to determine whether older adults (,65 years) need higher levels of supplementary vitamin D than young adults when attempting to replete vitamin D status in deficient subjects, i.e. those with levels of 25-hydroxyvitamin D less than 75,nmol/L. As data on repletion with vitamin D2 have recently been published, we restricted our discussion to the use of vitamin D3 from dietary supplements, prescriptions for large oral doses, and bolus dosing or injections. Most published dosing regimens failed to achieve 75,nmol/L in most all subjects, whether young adults (<65 years) or older adults (,65 years). Whether as daily or bolus oral supplementation, elderly subjects appeared to need more vitamin D3 compared with younger adults, however, baseline levels, endpoints, study duration, compliance, and other factors were different among studies. To ensure most subjects are replete in vitamin D, a daily dose of more than 50,,g (2000,IU) in younger and 125,,g (5000,IU) is required. Other strategies including bolus and loading doses are described. No study reported adverse effects of using oral intakes about the current upper level of 50,,g (2000,IU). [source] Heinrich der Teichner: Commentator and Critic of the Worlds of the Court and the AristocracyORBIS LITERARUM, Issue 3 2008Albrecht Classen In the late Middle Ages poets increasingly voiced severe criticism of the social conditions of their time; they especially targeted the world of the courts and aristocracy at large. One of the most outspoken representatives of this criticism was the fourteenth-century Austrian poet Heinrich der Teichner, heretofore fairly little studied and even less known among the reading public today. He certainly relied on the traditional topos of court criticism that can be traced back at least to the twelfth and eleventh centuries, but his comments about the courts and the nobility are extremely biting and explicit. This article identifies some of the key passages in Teichner's voluminous poetic oeuvre in which he offers poignant social, moral, and political commentary about the shortcomings of his time. Teichner can be counted among the leading voices of his time particularly because of his unabashed and outspoken discussion of fundamental shortcomings among the upper level of late medieval society.1 [source] A theory of nonlinear susceptibility in polaritonic band-gap materials doped with multi-level atomsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 8 2005D. Mukherji Abstract We have studied the nonlinear susceptibility in dispersive polaritonic band-gap (DPBG) materials in the presence of five-level impurity atoms. Initially, the atom is prepared in a coherent superposition of two levels |b, and |c,. The levels |b, and |c, are coupled to the upper level |a, with a coherent laser field. The nonlinear susceptibility has been calculated corresponding to transitions |a, , |c, and |a, , |b, using the equation of motion for the density matrix. The atomic system is interacting with the polariton reservoir. The effect of atom-polariton reservoir coupling on the imaginary part of the nonlinear susceptibility has been studied when the resonance energy lies in lower band of the polariton spectrum. It is found that by shifting the resonance energy away from the band edge, the system goes to the probe gain state. It is also found that by changing the intensity of the coherent laser field, the system switches from gain to loss state and vice-versa. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The Late Weichselian sea level history of the Kullen Peninsula in northwest Skåne, southern SwedenBOREAS, Issue 2 2001PER SANDGREN The Kullen Peninsula in northwest Skåne, at the time of the Weichselian deglaciation an island surrounded by the Kattegat Sea, is the earliest known deglaciated area in Sweden. Sediment stratigraphic and mineral magnetic properties, combined with radiocarbon dating, were used to determine and date the isolation of present-day lake basins from the sea. Significant environmental changes, which reflect the isolations, are supported by previously published palaeoecological data and cannot be related to climate changes. Basins situated above the marine limit (ML) have short (in the order of centimetres) minerogenic sequences that are magnetically characterized by low concentrations of detrital magnetite. In contrast, the pre-isolation sediments in basins below the ML, especially those deposited in sheltered positions in the landscape, have thick sequences (in the order of metres) of authigenic greigite-bearing sediments. Age determinations of the isolation level are based on the AMS radiocarbon dating of terrestrial plant macrofossil remains and previously published pollen stratigraphical investigations. Supported by the upper level of a sandy beach deposit preserved on the generally steep till covered slopes, the marine limit can be determined to 88,89 m a.s.l., which developed at the regional deglaciation c. 17000 calendar years ago. The results indicate that the deglaciation shoreline level remained fairly constant, relative to the sea level, for c. 1000 years and was followed by a gentle regression. The presented shoreline displacement curve from the Kullen Peninsula extends c. 1000 calendar years further back in time than any previously published records from the Swedish west coast. [source] The spatial pattern of summertime subtropical anticyclones over Asia and Africa: A climatological reviewINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 2 2010Azar Zarrin Abstract The National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) monthly mean reanalysis dataset has been used to analyze spatial variations of summertime subtropical anticyclones over the Asia,Africa region. The geopotential height and zonal wind components of 1000, 500, 200, and 100 hPa in a 30-year period (1971,2000) have been used to determine the spatial and temporal variations of the anticyclone centres, their monthly frequency and latitudinal axis variations during April,October. The results revealed that there is a clear difference in the location of the summer anticyclone centres in lower, middle and upper levels of the troposphere. In the lower levels, the Azores subtropical anticyclone is located at the east of North Atlantic. In the middle levels, the frequencies of anticyclone centre are concentrated over the northwest of Africa, Arabian Peninsula and Iranian Plateau. In the upper troposphere, the geographical location of the anticyclone centres and their frequencies in the summer season exhibit a scattered pattern from south of China up to western Iran at 200 hPa, and a bimodal pattern over the Tibetan and the Iranian Plateaus at 100 hPa. In fact, in the entire study domain, the Iranian Plateau is a preferable location of the middle and upper troposphere anticyclones. The highest observed latitude of the subtropical anticyclone at 100, 200 and 500 hPa levels have been seen over north of Tibetan plateau, a large area from east to west of Asia and Iran during August, July,August and July, respectively. The maximum monthly variation in the latitude of the ridgeline is seen at 500, 200, and 100 hPa from June to July which goes even up to 10 degrees at some longitudes. Copyright © 2009 Royal Meteorological Society [source] Seasonal variability in the response of the airflow characteristics to the changes in the macro-scale westerly flow intensity over Europe, 1971,2000INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 4 2009Michal Marosz Abstract The aim of the research was to identify the seasonal variability of correlation between the air motion characteristics and common zonal circulation index (Rossby's Index). Air flow characteristics comprised divergence and vorticity. The spatial coverage of the research was the so called Euro-Atlantic Region covering parts of North Atlantic and Europe (40W,40E, 35N,75N). Temporal extent was 1971,2000 thus matching the latest WMO normal period. The data used was the components of the wind vector (u,zonal component, v,meridional component) and geopotential heights (hgt) from NCEP/NCAR Reanalysis. The response of the vorticity field is apparent and the greatest variability is noted at 1000 hPa. The mid and upper levels in the troposphere reveal quite homogenous response of vorticity to the macro-scale forcing. The response of the divergence field is also apparent though more complex in the vertical profile of the troposphere. The analysis of correlation was followed by the description of annual as well as seasonal shape of vorticity and divergence fields in the extremes of Rossby Index. Copyright © 2008 Royal Meteorological Society [source] Characteristics of wintertime daily and extreme minimum temperature over South KoreaINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 2 2004Sang-Boom Ryoo Abstract In South Korea, consecutive positive temperature anomalies have been observed since the mid-1980s. The objective of this study is to assess the recent trends in, and variability of, daily minimum temperature over South Korea with particular emphasis on its extremes. Temporal characteristics of wintertime daily and extreme minimum temperature-related variables were analysed on a seasonal basis for the period of 1958,59 to 2000,01. The results show continually fewer days with extreme low minimum temperature since the mid-1980s. However, no significant change in the 1 day temperature difference was observed during the same period, indicating little change in the frequency of cold surges. Also, during the period analysed, there is a significant positive trend in the seasonal mean temperature, a negative trend in the frequency of the extreme cold days, and no significant trend in the seasonal occurrence of cold surges. Northern Hemisphere geopotential height fields before and after 1986,87, i.e. the start of successive positive anomalies in the winter surface air temperature over South Korea, showed a substantial decrease throughout the troposphere over the polar region. In the upper levels the overall pattern becomes more wavelike, with eddies embedded between meanders. The differences in the lower troposphere are remarkably similar to the Arctic oscillation, although the centre in the North Atlantic is shifted toward western Europe and differences in the North Pacific are relatively weaker than those in the polar region. The recent positive phase of the Arctic oscillation may contribute to these abrupt changes in wintertime daily minimum temperatures over South Korea. El Niño,southern oscillation phenomena appear to contribute to the interannual variation of cold surge days in South Korea. Years with no cold surges were experienced during La Niña episodes. On the other hand, all years with more than four cases of cold surges were during El Niño episodes. Copyright © 2004 Royal Meteorological Society [source] Observed and SST-forced seasonal rainfall variability across tropical AmericaINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 12 2001Vincent Moron Abstract Three experiments starting from different initial conditions have been made with the ECHAM-4 atmospheric General Circulation Model (GCM) integrated at T30 resolution forced with the observed sea-surface temperature (SST) over the period 1960,1994. The tropical America modes of seasonal rainfall anomalies whose time variation is most accurately simulated by the GCM have been searched for using Singular Value Decomposition Analyses (SVDA) and Canonical Correlation Analysis (CCA) between observed and model fields. The leading modes revealed by SVDA and CCA are highly similar, even though the ordering of the modes showed some fluctuation. A first skilful rainfall anomaly mode has weights of the same sign almost everywhere in tropical America, except along the western coast and the sub-tropical margins. This mode appears in all of the four seasons assessed. A second major skilful mode is usually a bipolar north,south (N,S) rainfall anomaly pattern (clear in December,March, DJFM; March,May, MAM; and June,September, JJAS). A large portion of the skill of the first rainfall anomaly mode (same sign anomalies across tropical America except small patches along the western coast) is through variance that is in common with the Southern Oscillation Index (SOI). In addition to forcing from the central/eastern tropical Pacific SST, there also appears a contribution from contrasting SST anomalies in the tropical Atlantic. This rainfall mode is usually a regional portion of a more large-scale mode encompassing at least the whole tropical zone (especially in DJFM, MAM and September,November, SON). Analysis of the relationship of this mode with GCM circulation features reveals that a rainfall deficit (respectively excedent) over the main rainbelt of the tropical America region is associated with strengthening (respectively weakening) of the sub-tropical westerly jet streams, a global warming (respectively cooling) of the tropical atmosphere, an anomalous divergence (respectively convergence) in the lower levels and an anomalous convergence (respectively divergence) in the upper levels over tropical America and in the region of the Atlantic Inter-tropical Convergence Zone (ITCZ). Such global features are not so apparent for the dominant mode of JJAS, even though the correlations with El Niño,Southern Oscillation (ENSO) indicators (as SOI or NINO3 SST index) are as high as for the other seasons. The bipolar N,S rainfall anomaly mode in tropical America is mostly related to anomalous N,S gradient of SST anomalies in the tropical Atlantic. The atmospheric circulation anomalies emphasize changes in 850 hPa meridional winds in the tropical Atlantic. However, there is also interannual variance of this rainfall mode in both the model and observations that is unexplained by tropical Atlantic SSTs, but which is explained by central/eastern tropical Pacific SSTs and, potentially, SSTs from other tropical and extratropical areas. This is especially true in MAM. Some differences in the details of the model and observed teleconnection patterns are noted. Such differences can be used to statistically adjust the model simulations using the CCA or SVDA modes as basis patterns. Both statistical approaches have been applied and the results are consistent between the two. The increase of skill is stronger when temporal correlation (the pattern correlation) between the model and observed pattern is high (low) as for JJAS. The skill is moderate to high around the whole Amazon basin, but remains relatively low inside the Amazon basin, though reliability of the observations themselves may influence this result. Averaged over all the seasons, about 15,35% (35,55%) of the interannual grid-box (regional) seasonal rainfall variance is skilfully simulated from the observed SST forcing. Copyright © 2001 Royal Meteorological Society [source] Plural Cities and Ethnic Enclaves: Introducing a Measurement Procedure for Comparative StudyINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 2 2002Michael Poulsen World cities attract two major streams of migrants , those who occupy the upper levels of their occupational hierarchies (the ,globalized professionals') on the one hand and marginalized, low,skill workers on the other. These two groups are often of different ethnic status, and it is argued that multicultural world cities are thus fractured in both their labour and housing markets along ethnic as well as economic lines. There has been little formal testing of these ideas, however. In this introductory article we introduce a method that can be used for comparative studies of residential fragmentation , an index of residential concentration , and apply it to three cities which have experienced rapid, multiethnic immigration in recent decades (New York, Sydney and Auckland). The patterns displayed indicate much greater fragmentation in New York than in the other two cities, suggesting that the ,conventional wisdom' regarding ethnic residential patterns may over,emphasize ,American exceptionalism'. Les villes mondiales attirent deux grands flux de migrants: ceux qui occupent les niveaux supérieurs de leurs hiérarchies professionnelles (les ,experts mondialisés') d'une part, et les travailleurs peu qualifiés et marginalisés, de l'autre; ces deux groupes sont souvent de statut ethnique différent. De ce fait, ces grandes villes multiculturelles subissent, dit,on, une fracture de leurs marchés du travail et du logement selon des critères à la fois ethniques et économiques , affirmations qui ont rarement été mises à l'épreuve. Cet article introductif présente une méthode utilisable dans des études comparatives de fragmentation résidentielle , indice de concentration résidentielle , en l'appliquant à trois villes ayant connu une rapide immigration multiethnique au cours des dernières décennies (New York, Sydney et Auckland). Les modèles obtenus indiquent une fragmentation bien plus importante à New York que dans les deux autres villes, suggérant que la ,croyance populaire'à l'égard des schémas résidentiels ethniques surestime peut,être ,l'exception américaine'. [source] Spinel,cordierite symplectites replacing andalusite: evidence for melt-assisted diapirism in the Bushveld Complex, South AfricaJOURNAL OF METAMORPHIC GEOLOGY, Issue 6 2004T. Johnson Abstract Spinel,cordierite symplectites partially replacing andalusite occur in metapelitic rocks within the cores of several country rock diapirs that have ascended into the upper levels of layered mafic/ultramafic rocks in the Bushveld Complex. We investigate the petrogenesis of these symplectites in one of these diapirs, the Phepane dome. Petrographic evidence indicates that at conditions immediately below the solidus the rocks were characterized by a cordierite-, biotite- and K-feldspar-rich matrix and 5,10 mm long andalusite porphyroblasts surrounded by biotite-rich fringes. Phase relations in the MnNCKFMASHT model system constrain the near-solidus prograde path to around 3 kbar and imply that andalusite persisted metastably into the sillimanite + melt field, where the fringing relationship between biotite and andalusite provided spatially restricted equilibrium domains with silica-deficient effective bulk compositions that focused suprasolidus reaction. MnNCKFMASHT pseudosections that model these compositional domains suggest that volatile phase-absent melting reactions consuming andalusite and biotite initially produced a moat of cordierite surrounding andalusite; reaction progressed until all quartz was consumed. Spinel is predicted to grow with cordierite at around 720 °C. Formation of the aluminous solid products was strongly controlled by the receding edge of andalusite grains, with symplectites forming at the andalusite-cordierite moat interface. Decompression due to melt-assisted diapiric rise of the floor rocks into the overlying mafic/ultramafic rocks occurred close to the thermal peak. Re-crossing of the solidus at P = 1.5,2 kbar, T > 700 °C resulted in preservation of the symplectites. Two features of the silica-deficient domains inhibited resorption of spinel. First, the cordierite moat armoured the symplectites from reaction with crystallizing melt in the outer part of the pseudomorphs. Second, an up- T step in the solidus at low- P, which may be in excess of 100 °C higher than the quartz-saturated solidus, resulted in high- T crystallization of melt on decompression. Even in metapelitic rocks where melt is retained, preservation of spinel is favoured by decompression. [source] Description and Prescription: How Gender Stereotypes Prevent Women's Ascent Up the Organizational LadderJOURNAL OF SOCIAL ISSUES, Issue 4 2001Madeline E. Heilman This review article posits that the scarcity of women at the upper levels of organizations is a consequence of gender bias in evaluations. It is proposed that gender stereotypes and the expectations they produce about both what women are like (descriptive) and how they should behave (prescriptive) can result in devaluation of their performance, denial of credit to them for their successes, or their penalization for being competent. The processes giving rise to these outcomes are explored, and the procedures that are likely to encourage them are identified. Because of gender bias and the way in which it influences evaluations in work settings, it is argued that being competent does not ensure that a woman will advance to the same organizational level as an equivalently performing man. [source] Lymphoscintigraphic and intraoperative detection of the sentinel lymph node in breast cancer patients: The nuclear medicine perspectiveJOURNAL OF SURGICAL ONCOLOGY, Issue 3 2004Giuliano Mariani MD Abstract The concept of sentinel lymph node biopsy in breast cancer surgery relates to the fact that the tumor drains in a logical way via the lymphatic system, from the first to upper levels. Therefore, (1) the first lymph node met (the sentinel node) will most likely be the first one affected by metastasis, and (2) a negative sentinel node makes it highly unlikely that other nodes are affected. Sentinel lymph node biopsy would represent a significant advantage as a mini-invasive procedure, considering that, after operation, about 70% of patients are found to be free from metastatic disease, yet axillary node dissection can lead to significant morbidity. Although the pattern of lymphatic drainage from a breast cancer can be very variable, the mammary gland and the overlying skin can be considered as a biologic unit in which lymphatics tend to follow the vasculature. Considering that tumor lymphatics are disorganized and relatively ineffective, subdermal, and peritumoral injection of small aliquots of radiotracer is preferred to intratumoral administration. 99mTc-labeled colloids with most of the particles in the 100,200 nm size range would be ideal for radioguided sentinel node biopsy in breast cancer. Lymphoscintigraphy is an essential part of radioguided sentinel lymph node biopsy, as images are used to direct the surgeon to the site of the node. The sentinel lymph node should have a significantly higher count than background. After removal of the sentinel node, the axilla must be re-examined to ensure all radioactive sites are identified and removed for analysis. The success rate of radioguidance in localizing the sentinel lymph node in breast cancer surgery is about 94,97% in Institutions where a high number of procedures are performed, approaching 99% when combined with the vital blue dye technique. At present, there is no definite evidence that a negative sentinel lymph node biopsy is invariably correlated with a negative axillary status, except perhaps for T1a-b breast cancers, with size ,1 cm. Randomized clinical trials should elucidate the impact of avoiding axillary node dissection in patients with a negative sentinel lymph node on the long-term clinical outcome of patients. J. Surg. Oncol. 2004;85:112,122. © 2004 Wiley-Liss, Inc. [source] The mRNA expression of P450 aromatase, gonadotropin ,-subunits and FTZ-F1 in the orange-spotted grouper (Epinephelus Coioides) during 17,-methyltestosterone-induced precocious sex changeMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 6 2007Weimin Zhang Abstract The orange-spotted grouper Epinephelus coioides is a protogynous hermaphroditic fish, but the physiological basis of its sex change remains largely unknown. In the present study, the 2-year-old orange-spotted grouper was induced to change sex precociously by oral administration of 17,-methyltestosterone (MT, 50 mg/Kg diet, twice a day at daily ration of 5% bodyweight) for 60 days. The serum testosterone levels were significantly elevated after MT treatment for 20 and 40 days as compared to control, but the levels of serum estradiol (E2) remained unchanged. The expression of P450aromA in the gonad significantly decreased after MT treatment for 20, 40, and 60 days. Accordingly, the enzyme activity of gonadal aromatase was also lower. The expression of FSH, subunit in the pituitary was significantly decreased after MT treatment for 20 days, but returned to the control levels after 40 and 60 days; however, the expression of LH, subunit was not altered significantly by MT treatment. The expression of FTZ-F1 in the gonad also decreased significantly in response to MT treatment for 40 and 60 days, but its expression in the pituitary was not altered significantly. Interestingly, when tested in vitro on ovarian fragments, MT had no direct effect on the expression of P450aromA and FTZ-F1 as well as the activity of gonadal aromatase, suggesting that the inhibition of gonadal P450aromatase and FTZ-F1 by MT may be mediated at upper levels of the brain-pituitary-gonadal axis. Taken together, these results indicated that FSH, P450aromA, FTZ-F1, and serum testosterone are associated with the MT-induced sex change of the orange-spotted grouper, but the cause,effect relationship between these factors and sex change in this species remains to be characterized. Mol. Reprod. Dev. 74: 665,673, 2007. © 2006 Wiley-Liss, Inc. [source] Synoptic scale wave breaking and its potential to drive NAO-like circulation dipoles: A simplified GCM approachTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 638 2009Torben Kunz Abstract Recent studies suggest a synoptic view of the North Atlantic oscillation (NAO) with its positive (negative) phase being the remnant of anticyclonic (cyclonic) synoptic scale wave breaking. This study examines the potential of anticyclonic (AB) and cyclonic wave breaking (CB) to drive NAO-like meridional circulation dipoles by investigating the synoptic evolution of AB and CB events in a mid-latitude eddy-driven jet in a simplified GCM with zonally uniform basic state. First, a method for the detection of such events from daily isentropic maps of potential vorticity and horizontal deformation is constructed. Then, from the obtained sample of events AB- and CB-composites of the upper and lower tropospheric flow are computed, and a distinct spatial and temporal asymmetry in the response to AB and CB events is found. While from the interaction of two AB events (with a mean lifetime of 2.6 days) a strong and short-lived positive phase NAO-like dipole is produced at the surface but not at upper levels, single CB events (4.3 days) are found to drive a strong and more persistent negative phase NAO-like dipole at upper levels but not at the surface. It is concluded that AB (CB) is not capable of driving a positive (negative) phase NAO-like dipole individually. However, the results suggest that equivalent barotropic NAO-like variability may arise from the successive occurrence of AB and CB events. Further, a sensitivity to the strength of the stratospheric polar vortex is found with more (less) frequent AB (CB) events under strong vortex conditions. Copyright © 2009 Royal Meteorological Society [source] Tropical-cyclone intensification and predictability in a minimal three-dimensional modelTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 636 2008Seoleun Shin Abstract We investigate the amplification and predictability of tropical cyclones in the context of a minimal, three-dimensional numerical model. In the prototype problem for intensification, starting with a tropical storm strength vortex in a quiescent environment on an f -plane, the emergent flow in the inner region of the vortex becomes highly asymmetric and dominated by deep convective vortex structures, even though the problem as posed is essentially axisymmetric. The details of the intensification process, including the asymmetric structures that develop, are highly sensitive to small perturbations in the low-level moisture field at the initial time. This sensitivity is manifest in a significant spread in the intensity of vortices from an ensemble of calculations in which random moisture perturbations are added in the lowest model level. Similar experiments are carried out on a ,-plane and in the case where there is an anticyclonic shear flow at upper levels. The former set shows no significant difference from the f -plane calculations in the evolution of intensity, but the latter set shows a significantly weaker vortex, contrary to a broadly held hypothesis that upper-level outflow channels are favourable to intensification. Copyright © 2008 Royal Meteorological Society [source] Dynamical budgets of the Antarctic Circumpolar Current using ocean general-circulation modelsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 607 2005A. Grezio Abstract Three general-circulation models (FRAM, OCCAM and POP) are used to investigate the dynamics of the Antarctic Circumpolar Current (ACC) at the latitudes of the Drake Passage where the ACC is unbounded. In these general circulation models, bottom form stress balances the wind stress in the momentum budgets. In the vorticity budgets, the main balance is between wind curl and bottom pressure torque in FRAM, OCCAM and POP. Moreover, in the ACC belt all topographic features are regions of nonlinearity and bottom pressure torque variations, with the Drake Passage playing the largest role. Transient eddy Reynolds stresses (TERSs) play a different role in the three models. In the upper levels, TERSs accelerate the flow in the POP and FRAM models, but decelerate the flow in OCCAM. The behaviour of TERSs change throughout the whole water column in the ACC belt and Reynolds stresses have a dragging effect on the flow below the levels where the topography starts to obstruct the flow. The total volume transport in three models is very different. Additionally, the different spatial resolution, which results in a different level of eddy kinetic energy, has a significant influence on the transport. Copyright © 2005 Royal Meteorological Society [source] Recombination lines and free-free continua formed in asymptotic ionized winds: Analytic solution for the radiative transferASTRONOMISCHE NACHRICHTEN, Issue 7 2009R. Ignace Abstract In dense hot star winds, the infrared and radio continua are dominated by free-free opacity and recombination emission line spectra. In the case of a spherically symmetric outflow that is isothermal and expanding at constant radial speed, the radiative transfer for the continuum emission from a dense wind is analytic. Even the emission profile shape for a recombination line can be derived. Key to these derivations is that the opacity scales with only the square of the density. These results are well-known. Here an extension of the derivation is developed that also allows for line blends and the inclusion of an additional power-law dependence beyond just the density dependence. The additional power-law is promoted as a representation of a radius dependent clumping factor. It is shown that differences in the line widths and equivalent widths of the emission lines depend on the steepness of the clumping power-law. Assuming relative level populations in LTE in the upper levels of He II, an illustrative application of the model to Spitzer/IRS spectral data of the carbon-rich star WR 90 is given (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] What Happened in the Trans-North China Orogen in the Period 2560-1850 Ma?ACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 6 2006Guochun ZHAO Abstract: The Trans-North China Orogen (TNCO) was a Paleoproterozic continent-continent collisional belt along which the Eastern and Western Blocks amalgamated to form a coherent North China Craton (NCC). Recent geological, structural, geochemical and isotopic data show that the orogen was a continental margin or Japan-type arc along the western margin of the Eastern Block, which was separated from the Western Block by an old ocean, with eastward-directed subduction of the oceanic lithosphere beneath the western margin of the Eastern Block. At 2550-2520 Ma, the deep subduction caused partial melting of the medium-lower crust, producing copious granitoid magma that was intruded into the upper levels of the crust to form granitoid plutons in the low- to medium-grade granite-greenstone terranes. At 2530-2520 Ma, subduction of the oceanic lithosphere caused partial melting of the mantle wedge, which led to underplating of mafic magma in the lower crust and widespread mafic and minor felsic volcanism in the arc, forming part of the greenstone assemblages. Extension driven by widespread mafic to felsic volcanism led to the development of back-arc and/or intra-arc basins in the orogen. At 2520-2475 Ma, the subduction caused further partial melting of the lower crust to form large amounts of tonalitic-trondhjemitic-granodioritic (TTG) magmatism. At this time following further extension of back-arc basins, episodic granitoid magmatism occurred, resulting in the emplacement of 2360 Ma, ,2250 Ma 2110,21760 Ma and ,2050 Ma granites in the orogen. Contemporary volcano-sedimentary rocks developed in the back-arc or intra-arc basins. At 2150-1920 Ma, the orogen underwent several extensional events, possibly due to subduction of an oceanic ridge, leading to emplacement of mafic dykes that were subsequently metamorphosed to amphibolites and medium- to high-pressure mafic granulites. At 1880-1820 Ma, the ocean between the Eastern and Western Blocks was completely consumed by subduction, and the closing of the ocean led to the continent-arc-continent collision, which caused large-scale thrusting and isoclinal folds and transported some of the rocks into the lower crustal levels or upper mantle to form granulites or eclogites. Peak metamorphism was followed by exhumation/uplift, resulting in widespread development of asymmetric folds and symplectic textures in the rocks. [source] Mentoring and organisational learning in research and developmentR & D MANAGEMENT, Issue 5 2005Liz Borredon This paper presents and discusses the contribution of ,mentoring' relationships to organisational learning and knowledge creation in the early stages of research and development (R&D) projects. Our study considers the characteristics of a scientific leader, the nature of the context he creates, and how dialogue contributes to scientific breakthrough. Our study is unusual in as much as research on knowledge creation has developed separately, yet in parallel, with that of mentoring. It is rare to combine these disciplines and yet our research shows there is much to learn from examining the two as a process. We conducted our research at TECHNO, a high-tech-based European company producing advanced equipment dedicated to particles acceleration. Interviews were carried out in 2002,2003 with the founder of the company, the head of the R&D and engineering department, and team members involved in the low energy cyclotron project. Our exploratory research enabled us to identify differences in actors' perceptions about the nature and characteristics of these relationships. Our study also suggests that not all sets of relationships can tolerate the degree of intensity provided by the ,mentor'. TECHNO has other ,mentors' who do not manage to generate the same creative context. Complementary mentoring styles based on premises and process reflection allow to support and enhance ,upper levels' learning by junior team members. We examine the nature of the leaders as mentors and catalysts within the learning process and briefly discuss implications for setting up and maintaining learning teams. 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