bluuebunny/crossref_metadata_2025 huggingface dataset:
Hitting a moving target: Acquisition of sound change in progress by Philadelphia children
Authors: Roberts Julie
Published: June 2009

Recent work in the acquisition of dialect has shown that children acquire patterns of stable variation and completed sound changes at a very early age. The present study looks at the acquisition of new sound changes by 3- and 4-year-old children. The results were consistent with previous findings in that, with critical exceptions, the children had acquired the changes. These results underscore the point that the dialect transmission period begins early – before the age of maximal peer group influence. In addition, as Labov (1994) suggested, one possible explanation for the frequent finding that women lead in changes from below is the asymmetry of the early childcare situation, which could advance female-dominated changes. The finding that children begin to learn their community norms at a very early age supports the possibility that this childcare asymmetry affects the progress of sound changes over time.
The variable deletion of unstressed vowels in Faialense Portuguese
Authors: Silva David James
Published: June 2009

To verify anecdotal claims regarding the nature of unstressed vowel deletion in Azorean (European) Portuguese, conversational data from a native speaker of the island of Faial have been analyzed to determine the segmental and prosodic contexts favoring elision. Results of a quantitative analysis indicate that unstressed [u] and schwa are the most likely vowels to be deleted; moreover, deletion is highly favored when the unstressed vowel occurs in word-final position at the end of an utterance. Factors such as rhythmic preservation, syllable structure, and functional load are discounted in the analysis, suggesting that vowel deletion is essentially a word-based variable process in the language.
Violable is variable: Optimality theory and linguistic variation
Authors: Guy Gregory R.
Published: June 2009

Optimality theory (OT) (McCarthy & Prince, 1993; Prince & Smolensky, 1993) has been proposed as a constraint-based theory of phonology in which the phonological facts of each language are accounted for by a language-specific ordering of a universal inventory of constraints. The constraints, expressing desirable (i.e., optimal) phonological states, evaluate possible candidate forms, selecting the optimal output. Any constraint may be violated by a surface form if it is overridden by a higherranked constraint; the ordinal sequence of constraints provides a weak quantification of constraint effects. Variability has been treated within OT by varying constraint orders. This model is analogous in several important respects to the variable rule model (VR) of Labov (1969) and Cedergren and Sankoff (1974). In VR, variable constraints express desirable phonological states which are variably realized on the surface, when not overridden by other constraints; constraints are probabilistically quantified. This article compares the OT and VR models, arguing that the VR model is superior on theoretical and empirical grounds: constraint effects in VR are stable, transparent, and learnable. Moreover, the probabilistic treatment of constraint effects allows VR to model successfully cases in which multiple violations of a single constraint lead to a cumulative reduction in likelihood of a form; such cases cannot be efficiently treated in OT.
Rural History and Popular Culture
Authors: Bellamy Liz , Snell K. D. M. , Williamson Tom
Published: June 2009

This issue of Rural History has greater thematic coherence than previous numbers, with all the papers having some relation to the study of ‘popular culture’, while coming from a variety of disciplinary perspectives. Each of the articles develops a key area of analysis, but their juxtaposition helps to raise further questions – about the kinds of sources that can be used to redress the bias towards the elite that has tended to dominate the study of culture, and about the problems involved in the handling of such sources. How do concepts of class, sectional, or gender interest relate to the sense of place and local identity? How can we detect such ideas within the historical record? How should we proceed in attempting to reconstruct popular and regional consciousness?
The Dragon of Wantley: Rural Popular Culture and Local Legend
Authors: Hey David
Published: June 2009

In one of the earliest issues of Rural History, Jacqueline Simpson urged students of Popular rural culture to examine local legends that centre upon some specific place, Person or object and which are a focus for local pride. Many of these are well-known tales which have been adapted, often in a humorous way, to local circumstances. Thus the seventy-odd stories of dragon-slaying which she has collected for Britain usually depict a local figure, not St George or a knight errant, as the hero. It is normally difficult, if not impossible, to explain how these tales began. The Dragon of Wantley, however, offers some unusual opportunities for delving into the historical context of a ballad that achieved national fame.
‘Wee be black as Hell’: Ritual, Disguise and Rebellion
Authors: Howkins Alun , Merricks Linda
Published: June 2009

This essay began from a continuity, or perhaps a persistence. Working as historians and cultural critics in very different periods, early modern England and the nineteenth-century countryside, we have both been struck for some years by continuities of behaviour in situations of riot or disorder. At one level this was first pointed to in the work of E.P. Thompson and George Rude in relation to eighteenth-century riot. Both these writers argued that far from riot being a spontaneous, anarchic and random event it was nearly always structured and organised. Thompson in particular introduced, through the notion of ‘moral economy’, the idea that rioters shared ideas about ‘right’ which Were related to an earlier customary social and economic order. From a very different, but equally important perspective, we have both been profoundly influenced by the flowering of cultural studies associated with the work of Mikhail Bahktin, and cultural anthropology growing from the work of Victor Turner and Pierre Bourdieu. In these Writers we found arguments about boundaries and structures which were both erected and transgressed by rituals of various kinds. Finally, a very few historians working on riot and popular disorder have been struck by the same continuity, notably, Michael Beames in his study of Whiteboyism, and very recently, Andrew Charlesworth in the Pages of this journal. This brief essay will seek to illuminate our notion of continuity, using some of these ideas. It is offered not as a definitive piece, but rather as an interpretation of some of these materials.
‘Lowther's Lambs’: Rural Paternalism and Voluntary Recruitment in the First World War
Authors: Grieves Keith
Published: June 2009

On the outbreak of war in August 1914 landowners in Sussex immediately started to employ their local leadership roles in the cause of voluntary recruiting and in doing so demonstrated the continuing utility of paternalistic social relations and the traditional rural structure to a nation preparing for war. The slow decline in social prestige provided by landownership was far from visible in the military sphere. As members of the military establishment – regular and territorial, past and present – landowners with clearly identifiable local economic, political and leisure interests attended to the search for recruits with the age old expectation that the deferential labourers would follow their ‘betters’ to war. As Alun Howkins has written,‘men were urged to go as much as part of their duty to the social structure of rural areas as to King and Country’.
Folklore Studies and the English Rural Myth
Authors: Bennett Gillian
Published: June 2009

Academic folklorists today define their subject matter in a way which runs counter to popular conceptions of the field, both as regards the ‘lore’ and the ‘folk’ part of this old composite term. They see the ‘lore’ as a body of beliefs, activities, ways of making, saying and doing things and interacting with others that are acquired through informal, unofficial channels by the processes of socialising in family, occupational, or activity-related groups. The ‘folk’ in the old sense of a group of people distinguishable by class, education or location therefore disappears from the modern equation, for it follows that we are all folk. As academic folklorists use the term nowadays, ‘folklore’ is best seen as a ‘cultural register’ – on the analogy of a linguistic register – one of several options available to members of a cultural grouping for thought, activity and interaction. It follows that ‘folklore’ can be found anywhere and among any group of people, urban as well as rural, professional as well as ‘peasant’.
Variable deletion of French /l/: linguistic, social and stylistic factors
Authors: Armstrong Nigel
Published: June 2009

This article considers variable /l/-deletion in the French definite articles, subject clitic pronouns and in one frequent phono-lexical context, exemplified bytable‘table’ andronfle‘snore’. It reports the treatment of /l/ by a sample of secondary schoolchildren from Lorraine in north-eastern France. The definite articles and subject clitics are considered on the one hand in relation to the linguistic constraints which influence /l/-deletion, and on the other to the extra-linguistic variables of age, sex and speech style. Variable /l/-deletion in the phono-lexical context referred to above is examined principally in relation to the lexical input which influences /l/-deletion. Finally, we consider whether the sociolinguistic patterns reported here are indicative of linguistic change in progress, or whether the effects observed are revelatory rather of attitudes to non-standard linguistic forms inculcated in speakers by normative French pedagogy.
Les malentendus communicatifs dans les conversations exolingues
Authors: Causa Maria
Published: June 2009

L'étude de la gestion des malentendus dans une situation de communication exolingue permet de suivre le développement de la compétence linguistique et communicative du locuteur non natif en langue cible et, plus particulièrement, d'observer les stratégies dont disposent les interactants pour (rè)ajuster leur discours et continuer ainsi la conversation. La mise en oeuvre de ces stratégies est fortement médiatisée par un ensemble de facteurs – externes et internes – qui constituent lc contexte interactionnel. L'analyse que nous proposons dans cet article ést elaborée à partir de malentendus produits pendant des entretiens entre locuteur natif (francophone) et locuteurs non natifs (italophones) enregistrés en France sur unc période de six mois.
Urban growth and royal interventionism in late medieval Castile
Authors: Valdivieso Isabel Del Val
Published: June 2009

Throughout the late Middle Ages, Castilian towns underwent a process of rapid economic and political growth which the monarchy sought to control. Accordingly, the monarchy reoriented its policies towards the towns. It attempted to impose the figure of the ‘corregidor’, the representative and defender of royal interests; it intervened wherever possible in the appointment of local government offices; it played its part in urban conflicts, alternately supporting opposing factions in an effort to take advantage of the situation and secure its own interests; and finally, the state established regulations governing economic activity. The process of royal intervention culminated under the Catholic monarchs (1474–1504) with what can be considered as a royal triumph.
Changing home and workplace in Victorian London: the life of Henry Jaques, shirtmaker
Authors: Pooley Colin G. , Turnbull Jean
Published: June 2009

The paper uses unusually rich evidence from a manuscript life history written in 1901 from personal diaries to explore the changing relationship between home and workplace in Victorian London. The life history of Henry Jaques demonstrates the way in which decisions about employment and residence were related both to each other and to stages of the family life course. The uncertainty of work, lack of income to support a growing family, rising aspirations, the constant threat of illness, the ease of moving between rented property, close ties between home and workplace, the stresses produced by home working, and the attractions of suburbanization all interacted to shape the residential and employment history of Jaques and his family. The themes exemplified by this detailed life history were also relevant to many other people. Evidence collected from a large-scale project on lifetime residential histories is used to place the experiences of Henry Jaques in a broader context, and to show how they related to the changing social and economic structure of Victorian London.
The structure of elite power in the early twentieth-century city: Norwich, 1900–35
Authors: Doyle Barry M.
Published: June 2009

Through a study of middle-class power in Norwich in the first third of the twentieth century, this paper tests a number of hypotheses concerning the behaviour of British urban elites. Analysis of networks (freemasons, business organizations and family) assesses the level of social unification among the middle class; elite involvement in chapel, charities and voluntary organizations addresses the question of social leadership; whilst elite politics is considered through three questions: did they become unified behind a single anti-socialist stance? Did the more important members of the elite leave urban politics? And did they abandon faith in grand civic projects? Its conclusions suggest that the power and involvement of the elite continued into the 1930s, maintaining a positive approach to the scope and function of municipal authority.
Tenements to bungalows: class and the growth of home ownership before ‘World War II’
Authors: O'Carroll Annette
Published: June 2009

Which social groups were moving into owner occupation in Britain before the Second World War is a matter of controversy, with opposing claims that this involved mainly white-collar or skilled manual workers. Although reliable figures showing the growth of home ownership in this period are rare, data are available for Edinburgh which indicate that tenure development in the city probably resembled that of England and Wales rather than the rest of Scotland. The relationship between income and the cost of home ownership is examined and this suggests that the main social group to move into owner occupation were probably white-collar workers. However, an analysis of occupational information from housing across a range of values in the city shows that this movement also affected manual workers and that there was a strong association between the proportions in each social class and the average rateable value of areas of housing.
Research in urban history: a review of recent theses
Authors: Doyle Barry M.
Published: June 2009

This review consists of a broad, uncritical survey of recent unpublished doctoral theses. Unlike previous years, where a mixture of British and non-British dissertations have been discussed, this year all the studies under consideration were completed at British universities, mostly in 1995. As before, the theses mentioned were chosen because of their focus on aspects of urban historical research, whilst the short descriptions are based on the abstracts published in the Aslib Index to Theses [ASLIB]. Urban history, or research with a strong urban bias, would appear to be in a healthy state in Britain and there was no shortage of studies to choose from, a total of thirty-nine receiving attention in this report. This focus on recent research in one country provides the opportunity to take stock and make some observations about current trends as well as allowing comparisons to be drawn with previous years where there is both continuity and evidence of change. To complement this focus on Britain, the next report will assess the state of urban history research outside the United Kingdom, and especially in North America.
Definition of three somatic adult cell nuclear transplant methods in zebrafish (Danio rerio): before, during and after egg activation by sperm fertilization
Authors: Pérez-Camps M. , Cardona-Costa J. , Francisco-Simao M. , García-Ximénez F.
Published: June 2009

Zebrafish somatic nuclear transplant has only been attempted using preactivated eggs. In this work, three methods to carry out the nuclear transplant using adult cells before, during and after the egg activation/fertilization were developed in zebrafish with the aim to be used in reprogramming studies. The donor nucleus from somatic adult cells was inserted: (method A) in the central region of the egg and subsequently fertilized; (method B) in the incipient animal pole at the same time that the egg was fertilized; and (method C) in the completely defined animal pole after fertilization. Larval and adult specimens were obtained using the three methods. Technical aspects related to temperature conditions, media required, egg activation/fertilization, post-ovulatory time of the transplant, egg aging, place of the donor nucleus injection in each methodology are presented. In conclusion, the technical approach developed in this work can be used in reprogramming studies.
Obsessive-Compulsive Hoarding: A Cognitive-Behavioural Approach
Authors: Shafran Roz , Tallis Frank
Published: June 2009

Obsessive-compulsive hoarding can be viewed within personality, neuroethological and cognitive-behavioural frameworks. Three cases of obsessive-compulsive hoarding are described in detail. All cases had some insight (albeit fluctuating) into their problem and were seeking treatment. There was evidence of abnormal risk assessment, fear of criticism, excessive guilt, overconscientiousness and inflated responsibility. Depression, emotional or material deprivation and significant loss during childhood and adolescence were experienced by all cases. The cases are considered to be consistent with a cognitive-behavioural model of obsessive-compulsive disorder emphasizing the importance of learning and cognition. Implications for treatment are discussed.
The Relationship Between Problem-Solving and Autobiographical Memory in Parasuicide Patients
Authors: Sidley Gary L. , Whitaker Kim , Calam Rachel M. , Wells Adrian
Published: June 2009

The relationship between effectiveness of interpersonal problem-solving and specificity of autobiographical memory was examined for 35 patients admitted to an inner-city District General Hospital following a deliberate drug-overdose. The results replicated those of Evans, Williams, O'Loughlin and Howells (1992) in finding a significant correlation between ineffective problem-solving and the over-general retrieval of autobiographical memories, giving further support to the suggestion that an over-general memory database may underpin the problem-solving deficits characteristic of parasuicide patients. However, the correlation coefficient computed was notably lower than in the Evans et al. study and an attempt is made to explain this discrepancy on the basis of differences in the levels of psychopathology between the patients involved in each study.
An approach for improving the sampling efficiency in the Bayesian calibration of computationally expensive simulation models
Authors: Xie Hua , Eheart J. Wayland , Chen Yuguo , Bailey Barbara A.
Published: June 2009

In recent years, interest in the Bayesian approach for the calibration of hydrological and environmental simulation (HES) models has been growing. To extract useful information on unknown parameters produced in a Bayesian calibration, it is often necessary to rely on samples drawn from the posterior distribution. Sampling a posterior distribution requires a large number of evaluations of the simulation model, and the total computational costs could be prohibitively high when the simulation model is computationally expensive. A new computing strategy is proposed in this paper to alleviate this computational difficulty by making better use of the information generated in a costly run of the HES model by using multiple evaluations of the posterior density in the less computationally expensive subspace of error model parameters. A multiple‐try Markov chain Monte Carlo (MCMC) algorithm is designed to implement this idea and is benchmarked with the Metropolis‐Hastings algorithm, a basic recipe for MCMC sampling. The results show that the proposed strategy has potential for improving the computational efficiency of posterior sampling and easing its implementation in the Bayesian calibration of computationally expensive HES models.
Geomagnetic field for 0–3 ka: 1. New data sets for global modeling
Authors: Donadini F. , Korte M. , Constable C. G.
Published: June 2009

Paleomagnetic and archeomagnetic records are used in both regional and global studies of Earth's magnetic field. We present a description and assessment of five newly compiled data sets, also used in the companion paper by Korte et al. (2009) to produce a series of time‐varying spherical harmonic models of the geomagnetic field for the last 3000 years. Data are drawn from our compilation of lake sediment records and from the online database, GEOMAGIA50v2. The five selections are available from the EarthRef Digital Archive at http://earthref.org/cgi‐bin/erda.cgi?n=944. Data are grouped according to the source of material, and we conducted separate assessments of reliability for archeomagnetic artifacts and lava flows (the ARCH3k_dat data set) and for sediments (SED3k_dat). The overall number of data is 55% greater than in previous compilations. Constrained data sets were selected using different criteria for each group. Winnowing of archeological data was based on uncertainties supplied by the original data providers. The lake sediment data assessment relied on preassigned age uncertainties and one or more of the following: comparisons with archeomagnetic data from the same region, regional consistency among several lakes, and consistency with global archeomagnetic models. We discuss relative merits of a larger unconstrained data set or a smaller (possibly) more reliable one. The constrained data sets eliminate a priori up to 35% of the available data in each case and rely on potentially subjective assessments of data quality. Given the limited data available our analyses indicate that iterative rejection of a small number (1–1.5%) of outlying data during global field modeling is a preferable approach. Specific regional comparisons among the models and data support the conclusion that Korte et al.'s outlier‐free CALS3k.3 model based on all available measurements from sediments and archeological artifacts currently provides the best global representation of the 0–3 ka field; the ARCH3k.1 model provides a better fit to the denser European archeomagnetic data and may be better in that region.
Geomagnetic field for 0–3 ka: 2. A new series of time‐varying global models
Authors: Korte M. , Donadini F. , Constable C. G.
Published: June 2009

Steadily increasing numbers of archeomagnetic and paleomagnetic data for the Holocene have allowed development of temporally continuous global spherical harmonic models of the geomagnetic field extending present and historical global descriptions of magnetic field evolution. The current work uses various subsets of improved data compilations, details of which are given in a companion paper by Donadini et al. (2009), and minor modifications of standard modeling strategies (using temporally and spatially regularized inversion of the data and cubic spline parameterizations for temporal variations) to produce five models with enhanced spatial and temporal resolution for 0–3 ka. Spurious end effects present in earlier models are eliminated by enforcing large‐scale agreement with the gufm1 historical model for 1650–1990 A.D. and by extending the model range to accommodate data older than 3 ka. Age errors are not considered as a contribution to data uncertainties but are included along with data uncertainties in an investigation of statistical uncertainty estimates for the models using parametric bootstrap resampling techniques. We find common features but also significant differences among the various models, indicating intrinsic uncertainties in global models based on the currently available Holocene data. Model CALS3k.3 based on all available archeomagnetic and sediment data, without a priori quality selection, currently constitutes the best global representation of the past field. The new models have slightly higher dipole moments than our previous models. Virtual axial dipole moments (VADMs) calculated directly from the data are in good agreement with all corresponding model predictions of VADMs. These are always higher than the spherical harmonic dipole moment, indicating the limitations of using VADMs as a measure of geomagnetic dipole moments.
Do all raindrops fall at terminal speed?
Authors: Montero‐Martínez Guillermo , Kostinski Alexander B. , Shaw Raymond A. , García‐García Fernando
Published: June 2009

A unique relation between raindrop size and fall speed vt(D) is assumed throughout atmospheric science. Yet, our speed versus size measurements of millions of drops during natural rainfall events show that many intermediate sized raindrops fall up to an order of magnitude faster than expected. Furthermore, images of drop clusters reveal that these “super‐terminal drops” are differently sized fragments of a recent break‐up, moving with the speed of the parent drop and relaxing towards vt(D). Additional evidence of the break‐up conjecture includes: (i) positive skewness in the distribution of fall speed deviations, (ii) strong size dependence of fall speed deviations and their maximum values and, (iii) preponderance of super‐terminal drops in the presence of large raindrops (i.e., during periods of high rainfall rates).
Sudden drop of seismic velocity after the 2004 Mw 6.6 mid‐Niigata earthquake, Japan, observed with Passive Image Interferometry
Authors: Wegler U. , Nakahara H. , Sens‐Schönfelder C. , Korn M. , Shiomi K.
Published: June 2009

Passive Image Interferometry (PII) is a seismological method employing ambient seismic noise to monitor the temporal evolution of mean shear wave velocity within the Earth. First, the elastic Green's tensor between two seismometers is computed from the cross correlation of seismic noise recorded during a certain period. Second, the constructed seismograms of different time periods are treated as earthquake multiplets, and small time shifts in their coda are used to invert a relative change in mean shear wave velocity. When applied to the source region of the 2004 Mw = 6.6 mid‐Niigata earthquake, Japan (centroid depth 5 km), we used noise recorded at six seismometers located at a distance of less than 25 km from the epicenter. Daily inversions during the 2 months before and after the earthquake show a sudden drop of mean shear wave velocity of some tenths of a percent at the time of the mid‐Niigata earthquake. Using noise in two frequency bands, 0.1–0.5 Hz and 2–8 Hz, we find similar amplitudes for the velocity drop, which indicates that changes are not restricted to the shallow subsurface. Possible interpretations of this velocity decrease are a decrease of crustal stress after the earthquake, a nonlinear site response in the shallow subsurface layer due to strong ground motion, or structural weakening due to the creation of new fractures in the source area of the earthquake.
Discontinuity structure of the mantle transition zone beneath the North China Craton from receiver function migration
Authors: Chen Ling , Ai Yinshuang
Published: June 2009

A better understanding of the significant Phanerozoic tectonic reactivation and destruction of the North China Craton (NCC) demands a detailed knowledge of the deep structural features of the region. We applied the wave equation‐based poststack migration technique to a combined receiver function data set from more than 250 broadband seismic stations to construct the structural image of the mantle transition zone beneath the NCC. Our imaging results reveal a relatively simple and flat 410‐km discontinuity but a structurally complicated 660‐km discontinuity beneath the region. Double discontinuities and a ∼30‐km depression of the 660‐km discontinuity are observed locally in the southern part of the eastern NCC, in contrast to the smoothly varying structure to the north and in the central and western parts of the craton. Distinctly rapid variations in both the 660‐km discontinuity structure and mantle transition zone thickness were found across the north‐south gravity lineament (NSGL) near the boundary between the eastern and central NCC, which probably reflects different thermal and probably chemical properties on the two sides of the NSGL. These differences are possibly associated with the Pacific slab, which is imaged tomographically as a flat‐lying structure in the mantle transition zone under the region east of the NSGL. The structural variation in the deep upper mantle appears to coincide with the sudden changes in surface topography, gravity field, and crustal and lithospheric structures as well, indicating that the two domains may have tectonically deformed differently throughout the whole upper mantle during the Phanerozoic cratonic destruction. The mantle transition zone on the eastern side of the NSGL is up to 30 ∼ 40 km thicker than the global average; this thickness and the complex structure of the 660‐km discontinuity in this region may reflect the strong influence that the deep subduction and stagnancy of the Pacific slab, and its possible sporadic penetration into the lower mantle, have had on mantle dynamics and lithospheric reactivation in the eastern NCC since the Mesozoic time. On the other hand, the less variable structure and normal‐to‐thin mantle transition zone imaged beneath the central and western NCC may indicate that the India‐Eurasia collision has had a relatively weak effect on the Cenozoic tectonics of these regions.
High‐amplitude variations in North Atlantic sea surface temperature during the early Pliocene warm period
Authors: Lawrence Kira T. , Herbert Timothy D. , Brown Catherine M. , Raymo Maureen E. , Haywood Alan M.
Published: June 2009

We provide the first continuous, orbital‐resolution sea surface temperature (SST) record from the high‐latitude North Atlantic, a region critical to understanding the origin of the Plio‐Pleistocene ice ages and proximal to regions that became frequently glaciated after ∼2.7 Ma. We analyzed sediments from Ocean Drilling Program Site 982 over the last 4 Ma for their alkenone unsaturation index and compared this surface water signal to a benthic δ18O record obtained from the same section. We find that while ocean surface temperatures were significantly warmer (∼6°C) than modern temperatures during the early Pliocene, they were also as variable as those during the late Pleistocene, a surprising result in light of the subdued variance of oxygen isotopic time series during the interval of 3–5 Ma. We propose two possible explanations for the high orbital‐scale SST variability observed: either that a strong, high‐latitude feedback mechanism not involving large continental ice sheets alternately cooled and warmed a broad region of the northern high latitudes or that by virtue of its location near the northern margin of the North Atlantic Drift, the site was unusually sensitive to obliquity‐driven climate shifts. On supraorbital time scales, a strong, sustained cooling of North Atlantic SSTs (∼4.5°C) occurred from 3.5 to 2.5 Ma and was followed by an interval of more modest cooling (an additional 1.5°C) from 2.5 Ma to the present. Evolutionary orbital‐scale phase relationships between North Atlantic SST and benthic δ18O show that SST began to lead δ18O significantly coincident with the onset of strong cooling at Site 982 (∼3.5 Ma). We speculate that these changes were related to the growth and subsequent persistence of a Greenland ice sheet of approximately modern size through interglacial states.
A nonparametric approach for paleohydrologic reconstruction of annual streamflow ensembles
Authors: Gangopadhyay Subhrendu , Harding Benjamin L. , Rajagopalan Balaji , Lukas Jeffrey J. , Fulp Terrance J.
Published: June 2009

As multicentury records of natural hydrologic variability, tree ring reconstructions of streamflow have proven valuable in water resources planning and management. All previous reconstructions have used parametric methods, most often regression, to develop a model relating a set of tree ring data to a target hydrology. In this paper, we present the first development and application of a K nearest neighbor (KNN) nonparametric method to reconstruct naturalized annual streamflow ensembles from tree ring chronology data in the Upper Colorado River Basin region. The method is developed using tree ring chronologies from the period 1400–2005 and naturalized streamflow from the period 1906–2005 at the important Lees Ferry, Arizona, gauge on the Colorado River to develop annual streamflow ensembles for this gauge for the 1400–1905 period. The proposed KNN algorithm was developed and tested using cross validation for the overlap period, i.e., the contemporary observed period for which both the tree ring and streamflow data are available (1906–2005). The cross‐validated streamflow reconstructions for the selected contemporary period compare very well with the observed flows and also with published parametric streamflow reconstructions for this gauge. The proposed nonparametric method provides an ensemble of streamflows for each year in the paleohydrologic reconstruction period (1400–1905) and, consequently, a more realistic asymmetric confidence interval than one obtained through most parametric approaches. Also, the K nearest neighbors are obtained only from the tree ring chronology data, and thus, the method can be used to reconstruct structured and even nonnumerical data for use in water resources modeling.
A kinematic mechanism for positive feedback between synoptic eddies and NAO
Authors: Ren Hong‐Li , Jin Fei‐Fei , Kug Jong‐Seong , Zhao Jing‐Xia , Park Juhyun
Published: June 2009

A kinematic mechanism for the positive feedback between the North Atlantic Oscillation (NAO) and synoptic eddies are depicted based on observational data analyses. Using three‐point rescaled covariance statistics of band‐pass‐filtered (2–8 days) synoptic eddy fields, we examined observed eddy structure changes associated with winter‐mean NAO anomalous flow. It is demonstrated that the NAO flow anomalies systematically deform the structures of recurring synoptic eddies to generate seasonal‐mean eddy‐vorticity flux anomalies predominately directed to the left‐hand side of the NAO flow anomalies. These anomalous eddy‐vorticity fluxes converge into the cyclonic center and diverge from the anticyclonic center of the anomalous NAO flow, and thus enhance the NAO flow.
Atmospheric condensed‐phase reactions of glyoxal with methylamine
Authors: De Haan David O. , Tolbert Margaret A. , Jimenez Jose L.
Published: June 2009

Glyoxal reacts with methylamine in drying cloud droplet/aerosol surrogates to form high molecular mass oligomers along with smaller amounts of 1,3‐dimethylimidazole and light‐absorbing compounds. The patterns observed by high‐resolution time‐of‐flight aerosol mass spectrometry indicate that oligomers form from repeated imine units. The reactions are 1st order in each reactant: rate‐limiting imine formation is followed by rapid dimer and oligomer formation. While excess methylamine evaporates from the droplet, half the glyoxal does not, due to self‐oligomerization reactions that occur in the absence of methylamine. Glyoxal irreversibly traps volatile amine compounds in the aerosol phase, converting them into oligomers. This is the first reported mechanism for the formation of stable secondary organic aerosol (SOA) material from methylamine, a substance with only one carbon, and could produce as much as 11 Tg SOA yr−1 globally if glyoxal reacts exclusively by this pathway.
Asian summer monsoon simulated by a global cloud‐system‐resolving model: Diurnal to intra‐seasonal variability
Authors: Oouchi Kazuyoshi , Noda Akira T. , Satoh Masaki , Wang Bin , Xie Shang‐Ping , Takahashi Hiroshi G. , Yasunari Tetsuzo
Published: June 2009

Interaction of convection and circulation is key to the Asian summer monsoon, but difficult to represent in global models. Here we report results from simulations for the summer of 2004 by a global cloud‐system‐resolving model, NICAM. At both 14‐ and 7‐km horizontal resolution, NICAM simulates the observed monsoon circulation patterns, and the northward propagation of precipitation. The 7‐km run simulates summer‐mean precipitation maxima in narrow bands along the western Ghats, Himalayan foothills, the Arakan Yoma highlands, and the Annamite range. Precipitation 1) is modulated by orography, 2) is affected by synoptic‐scale systems, and 3) displays a pronounced diurnal cycle, especially over Indo‐China, with its strong/weak signal propagating westward/eastward in the wet/dry phase of the intraseasonal oscillation. This set of simulations captures these intraseasonal changes of the Indian monsoon with high fidelity from June to early July. NICAM exhibits a positive bias in precipitation over the Indian Ocean, common to atmospheric models with prescribed sea surface temperature. This calls for the inclusion of ocean‐atmosphere coupling process to improve monsoon simulation skills.
Effect of aerosol on trade cumulus cloud morphology
Authors: Jiang Hongli , Feingold Graham , Koren Ilan
Published: June 2009

Large‐eddy simulations of trade wind cumulus clouds are conducted for clean and polluted aerosol conditions and at a number of different grid sizes to explore (1) the microphysical and morphological responses of fields of cumulus to aerosol perturbations and (2) the robustness of these responses to resolution. Cloud size distributions are shown to be well approximated by a negative power law function indicating that as resolution increases, more and more small clouds are resolved. Cloud fraction in the highest‐resolution simulations is 30% higher than in the coarse‐resolution simulations. Polluted cloud populations contain higher numbers of smaller clouds than clean cloud populations. Their frequency of convection is higher and lifetimes are shorter. The polluted clouds also tend to have higher cloud‐averaged liquid water contents. It is hypothesized that these responses are a result of a chain reaction set off by stronger evaporation at cloud edges in the case of polluted clouds. In all cases, the smallest clouds either dominate or contribute significantly to cloud fraction and cloud reflectance, in accord with recent satellite studies. The response of cloud fraction and liquid water path to aerosol changes is shown to be strongly dependent on the definition of what constitutes a “cloud,” suggesting that caution be exercised before parameterizing these responses.
Introduction to special section on Impacts of Land Use Change on Water Resources
Authors: Stonestrom David A. , Scanlon Bridget R. , Zhang Lu
Published: June 2009

Changes in land use have potentially large impacts on water resources, yet quantifying these impacts remains among the more challenging problems in hydrology. Water, food, energy, and climate are linked through complex webs of direct and indirect effects and feedbacks. Land use is undergoing major changes due not only to pressures for more efficient food, feed, and fiber production to support growing populations but also due to policy shifts that are creating markets for biofuel and agricultural carbon sequestration. Hydrologic systems embody flows of water, solutes, sediments, and energy that vary even in the absence of human activity. Understanding land use impacts thus necessitates integrated scientific approaches. Field measurements, remote sensing, and modeling studies are shedding new light on the modes and mechanisms by which land use changes impact water resources. Such studies can help deconflate the interconnected influences of human actions and natural variations on the quantity and quality of soil water, surface water, and groundwater, past, present, and future.
MIF-AMPK cascades
Authors: Ma Heng , Wang Jingying , Lane Erin , Leng Lin , Wang Wenkui , Ren Jun , Bucala Richard , Li Ji
Published: June 2009

Withdrawn for publication
The role of ongoing dendritic oscillations in single-neuron dynamics
Authors: Remme Michiel , Lengyel Mate , Gutkin Boris
Published: June 2009

The dendritic tree contributes significantly to the elementary computations a neuron performs while converting its synaptic inputs into action potential output. Traditionally, these computations have been characterized as temporally local, near-instantaneous mappings from the current input of the cell to its current output, brought about by somatic summation of dendritic contributions that are generated in spatially localized functional compartments. However, recent evidence about the presence of oscillations in dendrites suggests a qualitatively different mode of operation: the instantaneous phase of such oscillations can depend on a long history of inputs, and under appropriate conditions, even dendritic oscillators that are remote may interact through synchronization. Here, we develop a mathematical framework to analyze the interactions of local dendritic oscillations, and the way these interactions influence single cell computations. Combining weakly coupled oscillator methods with cable theoretic arguments, we derive phase-locking states for multiple oscillating dendritic compartments. We characterize how the phase-locking properties depend on key parameters of the oscillating dendrite: the electrotonic properties of the (active) dendritic segment, and the intrinsic properties of the dendritic oscillators. As a direct consequence, we show how input to the dendrites can modulate phase-locking behavior and hence global dendritic coherence. In turn, dendritic coherence is able to gate the integration and propagation of synaptic signals to the soma, ultimately leading to an effective control of somatic spike generation. Our results suggest that dendritic oscillations enable the dendritic tree to operate on more global temporal and spatial scales than previously thought.
Requirements for a single cell mechanism of entorhinal "grid field" activity: role of dendritic oscillators and coupling
Authors: Remme Michiel , Lengyel Máté , Gutkin Boris
Published: June 2009

The responses of rat medial entorhinal cortical neurons form characteristic grid patterns as a function of the animal’s position. A recent model of grid fields proposes a mechanism based on intrinsic single cell properties. It relies on interference patterns emerging from multiple distinct and independent oscillations maintained in the dendritic tree of the cell. Here we examine the requirements necessary to implement this idealized mechanism in a biophysically realistic model. We find that appropriate grid field-formation by a single cell is exquisitely sensitive to intra-dendritic interactions. Mathematical analysis shows how these effects depend on properties of the dendritic oscillators and the (active) membrane segments that connect them. We provide requirements on the ion channel distributions that would be necessary for grid-fields. We implement these requirements in a compartmental model of a spiny stellate cell. We find that with realistic cell properties the intra-dendritic coupling is insufficiently weak to maintain grid field activity. Rather, the cell acts as a single oscillator as opposed to maintaining several independent oscillators. This work gives explicit requirements for a single cell implementation of grid-field activity and hints at a possible circuit level origin for grid pattern formation.
At the crossroads of homoeostasis and disease: roles of the PACS proteins in membrane traffic and apoptosis
Authors: Youker Robert T. , Shinde Ujwal , Day Robert , Thomas Gary
Published: June 2009

The endomembrane system in mammalian cells has evolved over the past two billion years from a simple endocytic pathway in a single-celled primordial ancestor to complex networks supporting multicellular structures that form metazoan tissue and organ systems. The increased organellar complexity of metazoan cells requires additional trafficking machinery absent in yeast or other unicellular organisms to maintain organ homoeostasis and to process the signals that control proliferation, differentiation or the execution of cell death programmes. The PACS (phosphofurin acidic cluster sorting) proteins are one such family of multifunctional membrane traffic regulators that mediate organ homoeostasis and have important roles in diverse pathologies and disease states. This review summarizes our current knowledge of the PACS proteins, including their structure and regulation in cargo binding, their genetics, their roles in secretory and endocytic pathway traffic, interorganellar communication and how cell-death signals reprogramme the PACS proteins to regulate apoptosis. We also summarize our current understanding of how PACS genes are dysregulated in cancer and how viral pathogens ranging from HIV-1 to herpesviruses have evolved to usurp the PACS sorting machinery to promote virus assembly, viral spread and immunoevasion.
Prevention of myocardial fibrosis by N-acetyl-seryl-aspartyl-lysyl-proline in diabetic rats
Authors: Castoldi Giovanna , Di Gioia Cira R. T. , Bombardi Camila , Perego Carla , Perego Lucia , Mancini Massimiliano , Leopizzi Martina , Corradi Barbara , Perlini Stefano , Zerbini Gianpaolo , Stella Andrea
Published: June 2009

Ac-SDKP (N-acetyl-seryl-aspartyl-lysyl-proline) is a physiological tetrapeptide hydrolysed by ACE (angiotensin-converting enzyme). In experimental models of hypertension, Ac-SDKP has antifibrotic effects in the heart; however, the role of Ac-SDKP in diabetic cardiomyopathy is currently unknown. The aim of the present study was to evaluate the effect of Ac-SDKP on cardiac systolic and diastolic function, and interstitial and perivascular fibrosis in the heart of diabetic rats. Diabetes was induced in 55 Sprague–Dawley rats by streptozotocin injection. Control rats (n=18) underwent only buffer injection. Out of the 55 diabetic rats, 19 were chronically treated with insulin and 13 with the ACEI (ACE inhibitor) ramipril (3 mg·kg−1 of body weight·day−1). At 2 months after the onset of diabetes, Ac-SDKP (1 mg·kg−1 of body weight·day−1) was administered by osmotic minipumps for 8 weeks to eight control rats, 13 diabetic rats, seven diabetic rats treated with ramipril and nine insulin-treated diabetic rats. Diabetic rats had a significant increase in blood glucose levels. Left ventricular interstitial and perivascular fibrosis, and TGF-β1 (transforming growth factor-β1) protein levels were increased in diabetic rats, but not in insulin-treated diabetic rats and ramipril-treated diabetic rats, compared with control rats. Ac-SDKP administration significantly reduced left ventricular interstitial and perivascular fibrosis in diabetic rats and in diabetic rats treated with ramipril. This was accompanied by a significant reduction in active TGF-β1 and phospho-Smad2/3 protein levels in myocardial tissue of diabetic rats. Echocardiography showed that diabetes was associated with increased end-systolic diameters, and depressed global systolic function and diastolic dysfunction, as assessed by transmitral Doppler velocity profile. These changes were completely reversed by insulin or ramipril treatment. Ac-SDKP treatment partially restored diastolic function in diabetic rats. In conclusion, Ac-SDKP administration in diabetic rats reduces left ventricular interstitial and perivascular fibrosis, active TGF-β1 and phospho-Smad2/3 levels, and improves diastolic function. Taken together, these findings suggest that, by inhibiting the TGF-β/Smad pathway, Ac-SDKP protects against the development of diabetic cardiomyopathy.