bluuebunny/crossref_metadata_2025 huggingface dataset:
Robust explicit model predictive control for linear systems via interpolation techniques
Authors: Sui D. , Feng L. , Ong C. J. , Hovd M.
Published: July 2009

This paper presents a novel interpolation‐based model predictive control (IMPC) for constrained linear systems with bounded disturbances. The idea of so‐called ‘pre‐stabilizing’ MPC is extended by making interpolation among several ‘pre‐stabilizing’ MPC controllers, through which the domain of attraction can be magnificently enlarged. Compared with the standard ‘pre‐stabilizing’ MPC, the proposed approach has the advantage of combining the merits of having a large domain of attraction and a good behavior. Furthermore, such an IMPC problem can be solved off‐line by multi‐parametric programming. The optimal solution is given in an explicitly piecewise affine form. A simple algorithm for the implementation of the explicit MPC control laws is also proposed. Copyright © 2009 John Wiley & Sons, Ltd.
Unsupervised segmentation of conversational transcripts
Authors: Kummamuru Krishna , Padmanabhan Deepak , Roy Shourya , Venkata Subramaniam L.
Published: July 2009

Contact centers provide dialog‐based support to organizations to address various customer‐related issues. We have observed that calls at contact centers mostly follow well‐defined patterns. Such call flows could specify how an agent should proceed in a call, handle objections, persuade customers, follow compliance issues, etc., and could also help to structure the operational process of call handling. Automatically identifying such patterns in terms of distinct segments from a collection of transcripts of conversations would improve productivity of agents as well as enable easy verification of whether calls comply with guidelines. Call transcripts from call centers typically tend to be noisy owing to the noise arising from agent/caller distractions, and errors introduced by the speech recognition engine. Such noise makes classical text segmentation algorithms such as TextTiling, which work on each transcript in isolation, very inappropriate. But such noise effects become statistically insignificant over a corpus of similar calls. In this paper, we propose an algorithm to segment conversational transcripts in an unsupervised way utilizing corpus level information of similar call transcripts. We show that our approach outperforms the classical TextTiling algorithm and also describes ways to improve the segmentation using limited supervision. We discuss various ways of evaluating such an algorithm. We apply the proposed algorithm to a corpus of transcripts of calls from a car reservation call center and evaluate it using various evaluation measures. We apply segmentation to the problem of automatically checking the compliance of agents and show that our segmentation algorithm considerably improves the precision. Copyright © 2009 Wiley Periodicals, Inc., A Wiley Company
Towards an efficient reputation based hybrid key management architecture forad hocnetworks
Authors: Benazzouz Lamia , Elhdhili Mohamed Elhoucine , Kamoun Farouk
Published: July 2009

Common key management schemes are hard to deploy inad hocnetworks because of their infrastructure‐less nature and dynamic topology. In this paper, we propose a hybrid key management architecture that is adapted forad hocnetworks. The proposed architecture is based on a clustering algorithm called RECA that we have designed for security purposes inad hocnetworks. RECA allows an efficient division of the network into clusters managed by trustworthy clusterheads that are supervised by a reputation system. The hybrid key management architecture exploits this division for scalability and availability of security services. It considers each clusterhead as a certification authority (CA) for its members and implements a totally distributed CA over only clusterheads. Simulations results show that the proposed solution enhances security services availability in comparison with existing solutions. Copyright © 2009 John Wiley & Sons, Ltd.
Lsh Participates in DNA Methylation and Silencing of Stem Cell Genes
Authors: Xi Sichuan , Geiman Theresa M. , Briones Victorino , Guang Tao Yong , Xu Hong , Muegge Kathrin
Published: July 2009

Transcriptional control of stem cell genes is a critical step in differentiation of embryonic stem cells and in reprogramming of somatic cells into stem cells. Here we report that Lsh, a regulator of repressive chromatin at retrotransposons, also plays an important role in silencing of stem cell-specific genes such as Oct4. We found that CpG methylation is gained during in vitro differentiation of several stem cell-specific genes (in 11 of 12 promoter regions) and thus appears to be a common epigenetic mark. Lsh depletion prevents complete silencing of stem cell gene expression and moreover promotes the maintenance of stem cell characteristics in culture. Lsh is required for establishment of DNA methylation patterns at stem cell genes during differentiation, in part by regulating access of Dnmt3b to its genomic targets. Our results indicate that Lsh is involved in the control of stem cell genes and suggest that Lsh is an important epigenetic modulator during early stem cell differentiation.

Disclosure of potential conflicts of interest is found at the end of this article.
Dual SP/ALDH Functionalities Refine the Human Hematopoietic Lin−CD34+CD38− Stem/Progenitor Cell Compartment
Authors: Pierre-Louis Olivier , Clay Denis , Brunet de la Grange Philippe , Blazsek Istvan , Desterke Christophe , Guerton Bernadette , Blondeau Camille , Malfuson Jean-Valère , Prat Marie , Bennaceur-Griscelli Annelise , Lataillade Jean-Jacques , Le Bousse-Kerdilès Marie-Caroline
Published: July 2009

Identification of prevalent specific markers is crucial to stem/progenitor cell purification. Determinants such as the surface antigens CD34 and CD38 are traditionally used to analyze and purify hematopoietic stem/progenitor cells (HSCs/HPCs). However, the variable expression of these membrane antigens poses some limitations to their use in HSC/HPC purification. Techniques based on drug/stain efflux through the ATP-binding cassette (ABC)G2 pump (side population [SP] phenotype) or on detection of aldehyde dehydrogenase (ALDH) activity have been independently developed and distinguish the SP and ALDHBright (ALDHBr) cell subsets for their phenotype and proliferative capability. In this study, we developed a multiparametric flow cytometric method associating both SP and ALDH activities on human lineage negative (Lin−) bone marrow cells and sorted different cell fractions according to their SP/ALDH activity level. We find that Lin−CD34+CD38Low/− cells are found throughout the spectrum of ALDH expression and are enriched especially in ALDHBr cells when associated with SP functionality (SP/ALDHBr fraction). Furthermore, the SP marker identified G0 cells in all ALDH fractions, allowing us to sort quiescent cells regardless of ALDH activity. Moreover, we show that, within the Lin−CD34+CD38−ALDHBr population, the SP marker identifies cells with higher primitive characteristics, in terms of stemness-related gene expression and in vitro and in vivo proliferative potential, than the Lin−CD34+ CD38−ALDHBr main population cells. In conclusion, our study shows that the coexpression of SP and ALDH markers refines the Lin−CD34+CD38− hematopoietic compartment and identifies an SP/ALDHBr cell subset enriched in quiescent primitive HSCs/HPCs.
Different mechanisms of Ca2+regulation that influence synaptic transmission: Comparison between crayfish and Drosophila neuromuscular junctions
Authors: Desai‐Shah Mohati , Cooper Robin L.
Published: July 2009

A brief historical background on synaptic transmission in relation to Ca2+dynamics and short‐term facilitation is described. This study focuses on the mechanisms responsible for the regulation of intracellular calcium concentration ([Ca2+]i) in high output terminals of larvalDrosophilacompared to a low‐output terminal of the crayfish neuromuscular junction (NMJ). Three processes; plasmalemmal Na+/Ca2+exchanger [NCX], Ca2+‐ATPase (PMCA), and sarcoplasmic/endoplasmic Ca2+‐ATPase (SERCA) are important in regulating the [Ca2+]iare examined. When the NCX is compromised by reduced [Na+]o, no consistent effect occurred; but a NCX blocker KB‐R7943 decreased the excitatory postsynaptic potential (EPSP) amplitudes. Compromising the PMCA with pH 8.8 resulted in an increase in EPSP amplitude but treatment with a PMCA specific inhibitor carboxyeosin produced opposite results. Thapsigargin exposure to block the SERCA generally decreases EPSP amplitude. Compromising the activity of the above Ca2+regulating proteins had no substantial effects on short‐term depression. The Kum170TSstrain (with dysfunctional SERCA), showed a decrease in EPSP amplitudes including the first EPSP within the train. Synaptic transmission is altered by reducing the function of the above three [Ca2+]iregulators; but they are not consistent among different species as expected. Results in crayfish NMJ were more consistent with expected results as compared to theDrosophilaNMJ. It is predicated that different mechanisms are used for regulating the [Ca2+]iin high and low output synaptic terminals. Synapse 63:1100–1121, 2009. © 2009 Wiley‐Liss, Inc.
Synthese und Charakterisierung von binären Molekülverbindungen der Gruppe 15 Elemente mit P2As2‐, PSb2‐, PBi2‐, PBi3‐ und P2Bi4‐Gerüst
Authors: von Hänisch Carsten , Stahl Sven
Published: July 2009

The reaction of tBuPh2SiPLi2 with (Me3Si)2CHAsCl2 in molar ratio 1:1 yields the compound [(SiMe3)2CHAsPSitBuPh2]2 (1). The structure of 1 reveals the formation of a As2P2 ring compound. In contrast, the reactions of tBuPh2SiPLi2 with (Me3Si)2CHSbCl2 or (Me3Si)2CHBiCl2 yield the chloro bridged species [tBuPh2SiP{SbClCH(SiMe3)2}2] (2) and [tBuPh2SiP{BiClCH(SiMe3)2}2] (3). Starting from RMe2SiPLi2 (R = Thex, Me) the compounds [P{BiClCH(SiMe3)2}3] (4) and [P2{BiClCH(SiMe3)2}4] (5) were obtained from the reactions with (Me3Si)2CHBiCl2. The compounds 1 – 5 were characterised by single crystal X‐ray diffraction, elemental analysis as well as IR and NMR techniques.
Synthesis and Crystal Structure of a Bixbyite‐Type Solid Solution Zr0.43Er0.57O1.07N0.43
Authors: Meyer Stefanie , Martinez Meta Neil J. , Schweda Eberhard , Eibl Oliver
Published: July 2009

A powder of the composition 40 mol‐% Er2O3 and 60 mol‐% ZrO2 has been prepared. The anion deficient fluorite related compound Zr3Er4O12 [R\bar{3}: a = 971.79(7) pm and c = 907.976(0) pm] was produced. This precursor was treated with gaseous ammonia at temperatures between 25 and 1200 °C. The reaction was followed in situ by X‐ray diffraction in a high temperature reaction chamber under a constant flow of ammonia. The nitridation of Zr3Er4O12 led to a nitride oxide of the solid‐solution‐type with an apparent composition Zr0.43Er0.57O1.07N0.43 The compound crystallizes isostructural to bixbyite due to vacancy ordering [Ia\bar{3}: a = 1036.37(4) pm]. The reoxidation of the nitride oxide was monitored in DTA/TG experiments exhibiting an almost complete reoxidation to the starting composition except for some inclusions of dinitrogen.
Mucin‐producing bile duct tumors: radiological–pathological correlation and diagnostic strategy
Authors: Lim Jae Hoon , Jang Kee‐Taek
Published: July 2009

Mucin‐producing bile duct tumors are characterized by intraductal papillary tumors producing large amounts of mucin. The tumor comprises macroscopically prominent intraductal papillary neoplastic epithelia and produces a large amount of viscid mucin, resulting in dilatation of the bile ducts. The surface of the tumor is frond‐like, velvety, or serrated. The tumor exhibits five intraductal growth patterns; polypoid intraductal growth, mucosal spreading growth, cast‐like intraductal growth, cystic tumor, and intraductal floating tumors. Imaging features reflect the interplay between the morphology of the tumor, the amount of mucin production, and biliary dilatation. This review article describes the radiological manifestations of the tumor, based on pathological‐radiological correlation and biological behavior.
Four New Fatty Acid Esters from the Feces of Trogopterus xanthipes
Authors: Yang Nian‐Yun , Tao Wei‐Wei , Duan Jin‐Ao , Guo Jian‐Ming , Cao Ling‐Ling
Published: July 2009

Four new fatty acid esters have been isolated from Feces Trogopterus. Their structures were determined by spectroscopic and chemical methods to be bis(7‐hydroxyheptyl) icosanedioate (1), bis(7‐hydroxyheptyl) heptadecanedioate (2), bis(7‐hydroxyheptyl) decanedioate (3), and bis(7‐hydroxyheptyl) octanedioate (4). In the anticoagulative assay, compounds 3 and 4 had significant antithrombin activity.
Timing of surgical treatment for type III supracondylar humerus fractures in pediatric patients
Authors: Yildirim Ahmet Ozgur , Unal Vuslat Sema , Oken Ozdamar Fuad , Gulcek Murat , Ozsular Metin , Ucaner Ahmet
Published: July 2009

Background

Type III supracondylar humeral fracture is a common cause of emergency hospitalization among children requiring surgical treatment. The configuration of the internal fixation material, surgical technique, and optimal timing of surgery (TS) have always been popular topics of debate. The TS in uncomplicated cases is usually determined by surgeons.

Methods

In this study, we prospectively followed children with type III supracondylar fractures. We aimed to clarify the effects of injury side, gender, and post-injury delay on switching to open surgery and the ease of the reduction.

Results

Based on our results, the probability of switching to open surgery increased by a factor of 4 every 5 h beginning 15 h after injury. Open surgery was necessary after 32 h.

Conclusion

Reduction became technically more difficult as TS increased.
Human chorionic gonadotropin (hCG) prevents the transformed phenotypes induced by 17 β‐estradiol in human breast epithelial cells
Authors: Kocdor Hilal , Kocdor Mehmet A. , Russo Jose , Snider Kara E. , Vanegas Johana E. , Russo Irma H. , Fernandez Sandra V.
Published: July 2009

Human chorionic gonadotropin (hCG), a hormone produced during pregnancy, can elicit life‐long refractoriness to carcinogenesis by differentiation of the breast epithelium. Human breast epithelial cells MCF‐10F form tubules in collagen, mimicking the normal ductules. We have shown that 17 β‐estradiol (E2) alter the ductulogenic pattern of these cells. The effect of the recombinant hCG (rhCG) in vitro was evaluated on the transformation of MCF‐10F induced by E2. MCF‐10F cells were treated with 70 nM E2 alone or in combination with 50 IU/ml rhCG during 2 weeks, while the controls were treated with DMSO (the solvent in which E2 was dissolved) or rhCG alone. At the end of treatment, the cells were plated in type I collagen matrix (3D‐cultures) for detecting 2 main phenotypes of cell transformation, namely the loss of ductulogenic capacity and the formation of solid masses. Although E2 significantly increased solid mass formation, this effect was prevented when MCF‐10F cells were treated with E2 in combination with rhCG. Furthermore, E2 increased the main duct width (p < 0.001), and caused a disruption of the luminal architecture, whereas rhCG increased the length of the tubules (p < 0.001) and produced tertiary branching. In conclusion, rhCG was able to abrogate the transforming abilities of estradiol, and had the differentiating property by increasing the branching of the tubules formed by breast epithelial cells in collagen. These results further support our hypothesis, known as the terminal differentiation hypothesis of breast cancer prevention, that predicts that hCG treatment results in protection from tumorigenic changes by the loss of susceptible stem cells 1 through a differentiation to refractory stem cells 2 and increase differentiation of the mammary gland.
Delivery options and convexity in Treasury bond and note futures
Authors: Grieves Robin , Marcus Alan J. , Woodhams Adrian
Published: July 2009

Using Treasury bond and note futures to hedge fixed‐income portfolios is complicated by the large number of bonds that are eligible to deliver against the contract. Grieves and Marcus [Grieves, R. and A. Marcus. (2005). Delivery options and Treasury bond futures hedge ratios. Journal of Derivatives, 13, 70–76.] show that, in some circumstances, only two bonds—those with the highest and the lowest duration—are relevant for the hedging problem, which makes computation of analytic hedge ratios tractable. We evaluate the empirical efficacy of their two‐relevant‐bonds model. We compare the maturities of actual cheapest‐to‐deliver bonds to the prediction of the two‐deliverables model and calculate empirical price values of a basis point for Treasury futures contracts to determine whether contract prices display the negative convexity predicted by the model. The model has worked very well for the note contract and very poorly for the bond contract. We show that the difference in model performance is related to the shape of the yield curve.
Dietary capsanthin, the main carotenoid in paprika (Capsicum annuum), alters plasma high-density lipoprotein-cholesterol levels and hepatic gene expression in rats
Authors: Aizawa Koichi , Inakuma Takahiro
Published: July 2009

The effects of dietary capsanthin, the main carotenoid in paprika (Capsicum annuum), on lipid metabolism were examined. Young male Wistar rats were fed diets containing paprika powder, paprika organic solvent extract, residue of paprika extract, and purified capsanthin. Administration of purified capsanthin for 2 weeks resulted in a significant increase in plasma HDL-cholesterol (P < 0·05) without detectable differences in plasma total cholesterol and TAG concentrations. A statistically significant correlation (r0·567;P < 0·001) was found between dietary capsanthin concentrations and plasma HDL-cholesterol concentrations. Animals receiving diets containing two different capsanthin concentrations exhibited dose-dependent increases in plasma HDL-cholesterol (r0·597;P < 0·005). While capsanthin was absent in the liver of animals fed the basal diet, it increased markedly in capsanthin-fed animals (P < 0·001). Quantitative analyses of hepatic mRNA levels revealed that capsanthin administration resulted in up-regulation of mRNA for apoA5 and lecithin cholesterol acyltransferase (LCAT), without significant differences in other mRNA levels related to HDL-cholesterol metabolism. These results suggest that capsanthin had an HDL-cholesterol-raising effect on plasma, and the potential to increase cholesterol efflux to HDL particles by increasing apoA5 levels and/or enhancement of LCAT activity.
Neoliberalization and Transnational Capitalism in the American Mold
Authors: ELTEREN MEL VAN
Published: July 2009

This contribution focusses on the close intertwinement of Americanization, neoliberalism, and corporate globalization at the turn of the twenty-first century, on the eve of the global economic recession of 2008 and after. Many students of current globalization tend to reject the whole notion of Americanization. It is argued that these theorists have thrown the proverbial baby out with the bath water, namely an interest in America's strong influence in many domains globally. Yet it is also recognized that one has to move beyond a state-centrist approach in order to adequately grasp the significantly increased influence of transnational corporations over the past few decades. Therefore this article explores the major ways in which transnational corporations – in relation to US-dominated international governance – spread capitalist modernity worldwide. An attempt is made to explain how US business leaders and affiliated political power-holders managed to set the agenda of much of the global economy and why many of their foreign counterparts adopted similar neoliberal policies. The article concludes with a brief overview of major challenges and countermovements to the predominant form of capitalist globalization.
The Conservative Lobby and Nixon's “Peace with Honor” in Vietnam
Authors: SCANLON SANDRA
Published: July 2009

This essay explores the responses of conservative political activists to the Nixon administration's policy of “peace with honor” in Vietnam. Conservatives sought to influence the administration by acceptance of Vietnamization, a policy they interpreted as affording a more conventional prosecution of the war, and by pushing for increased aerial bombardment of North Vietnam, Laos and Cambodia. Divisions over the efficacy of détente derailed a unified conservative position on Vietnam and forced reassessments of the legitimacy of Nixon's promise of “peace with honor.” While highlighting the basic premises of conservative foreign policy during the late 1960s, this essay explores the means by which conservative leaders attempted to forge consensus regarding the Vietnam War and the impact of increased political power on the conservative movement's foreign-policy priorities.
“Women of Conscience” or “Women of Conviction”? The National Women's Committee on Civil Rights
Authors: LAVILLE HELEN
Published: July 2009

This paper explores the history of the National Women's Committee on Civil Rights (NWCCR). Called into being at the behest of President Kennedy, the NWCCR was an attempt to enlist the support of the organized women of America in the advancement of civil rights. The NWCCR had two main goals: first, to offer support for the passage of Kennedy's civil rights legislation, and second, to encourage their branch membership to work in support of integration. However, whilst the majority of the NWCCR's affiliated organizations had passed resolutions in favour of integration both throughout the United States and within their own organization, in practice they were reluctant to threaten the internal stability of their associations by insisting on either integrated membership or active support of civil rights in the local community. This article will argue that whilst the NWCCR were successful in organizing lobbying for the 1964 Civil Rights Act, they were unwilling to throw their weight behind efforts to encourage activism in local communities. Whilst key members of the NWCCR saw an important role for women in the implementation of civil rights at the community level, they were forced to conclude that the organizational structure and ethical inertia of the NWCCR did not make it a suitable medium for furthering racial justice.
Benjamin Franklin and the Leather-Apron Men: The Politics of Class in Eighteenth-Century Philadelphia
Authors: NEWMAN SIMON P.
Published: July 2009

Benjamin Franklin's autobiography reveals his deep investment in shaping and controlling how both his contemporaries and posterity assessed his life and achievements. This essay explores Franklin's construction and presentation of his pride in his working-class origins and identity, analysing how and why Franklin sought not to hide his poor origins but rather to celebrate them as a virtue. As an extremely successful printer, Franklin had risen from working-class obscurity to the highest ranks of Philadelphia society, yet unlike other self-made men of the era Franklin embraced and celebrated his artisanal roots, and he made deliberate use of his working-class identity during the Seven Years War and the subsequent imperial crisis, thereby consolidating his own reputation and firming up the support of urban workers who considered him one of their own.
From grapheme to word in reading acquisition in Spanish
Authors: CUETOS FERNANDO , SUÁREZ-COALLA PAZ
Published: July 2009

The relationship between written words and their pronunciation varies considerably among different orthographic systems, and these variations have repercussions on learning to read. Children whose languages have deep orthographies must learn to pronounce larger units, such as rhymes, morphemes, or whole words, to achieve the correct pronunciation of some words. However, children whose languages have transparent orthographies need only learn to pronounce graphemes to be able to read any word. In this study, the reading evolution of Spanish-speaking children was investigated for the purpose of discovering when and for what types of stimuli lexical information is used in Spanish. Five- to 10-year-old children were presented with lists of stimuli in which lexicality, frequency, and length were manipulated. The results in terms of reading accuracy and speed showed that the influence of stimulus length is great in the early grades and later diminishes, and just the opposite is the case for lexicality and frequency. These data suggest that reading acquisition in Spanish constitutes a continuum that ranges from phonological recoding to the use of lexical strategies, and that this transition is made at a very early stage, at least for the most frequent words.
Gender differences in language development in French Canadian children between 8 and 30 months of age
Authors: BOUCHARD CAROLINE , TRUDEAU NATACHA , SUTTON ANN , BOUDREAULT MARIE-CLAUDE , DENEAULT JOANE
Published: July 2009

The purpose of this article is to examine the language of girls and boys between 8 and 30 months of age, using the Quebec French version of The MacArthur Communicative Development Inventories. The findings from this parental report measure confirm those of earlier research, which showed the linguistic superiority of girls over boys at a young age. More specifically, the results show that girls produce significantly more words than boys; their utterances contain a greater number of grammatical forms, and are more complex syntactically. On the qualitative level, the data illustrate distinctive characteristics associated with gender in the acquisition of the first 100 words. These findings suggest that caution is necessary when assessing young children to interpret performance in light of factors that may contribute to it, including gender. These results are discussed in light of whether separate normative data are warranted for young boys and girls learning Canadian French.
Effects of forest age on fruit composition and removal in tropical bird-dispersed understorey trees
Authors: Lumpkin Heather A. , Boyle W. Alice
Published: July 2009

Little is known about how land-use changes affect interspecific interactions such as fruit–frugivore mutualisms. Forest age could affect both fruit sugar concentrations via differences in light availability or disperser abundance, and fruit removal rates via differences in bird and plant community composition. We examined how these two factors are affected by forest age in a Costa Rican rain forest. We compared seven young-secondary forest species, seven old-growth forest species, andMiconia nervosagrowing in both forests. We measured sugar concentrations in fruits and manipulated the location of paired fruiting branches, measuring subsequent fruit removal. Sugar concentration means were on average 2.1 percentage points higher in young-secondary forest species than in old-growth forest species, but did not differ amongMiconia nervosafruits from the two forests. Fruit removal rates were higher in young-secondary forest for 86% of young-secondary forest species, 71% of old-growth forest species, and on average for both young-secondary and old-growth forestMiconia nervosaindividuals. Higher sugar concentrations in young-secondary forest plants could reflect stronger competition for dispersers, while experimental fruit removal results suggests the opposite patterns of competition; fruits are more likely to be removed by dispersers in young-secondary forest independent of fruit nutrient concentration.
Characteristics of trees used as nest sites byApis dorsata(Hymenoptera, Apidae) in the Nilgiri Biosphere Reserve, India
Authors: Thomas Sumin George , Varghese Anita , Roy Pratim , Bradbear Nicola , Potts Simon G. , Davidar Priya
Published: July 2009

Nest site selection is critical for social insects since poor choices can heighten predation risks and result in reproductive failure (Frankset al. 2002). Social bees vary in their nest site requirements and among theApisbees in South Asia,Apis dorsataandA. floreanest in open combs, whereasApis cerananests in cavities (Crane 1999).Apis dorsataoften nests in aggregations, and the large open nests can be about 1.5 m wide and are located in sites such as cliff faces or on the underside of branches of tall trees that are inaccessible to most predators except skilled fliers and climbers (Crane 1999, Seeleyet al. 1982).Apis dorsata, which is widely distributed in tropical and subtropical Asia, is an important source of honey and wax for local communities, and understanding its nesting biology would help in the management and conservation of this economically important species.
Seed consumption by small mammals from Borneo
Authors: Wells Konstans , Corlett Richard T. , Lakim Maklarin B. , Kalko Elisabeth K. V. , Pfeiffer Martin
Published: July 2009

Fruit and seed consumers can both positively and negatively affect plant recruitment through seed dispersion and seed predation, respectively. In turn, fruits influence the abundance and distribution of consumers sustained by local plant assemblages. These interactions are key processes in plant recruitment and the dynamics of tropical forests, where most plants depend on dispersal by frugivorous animals (Corlett 1998). An understanding of these interactions and the functional role of particular seed-dispersing animals is increasingly important nowadays, given that human impact on tropical forest ecosystems may negatively impact seed dispersal and forest regeneration in both natural and human-altered forests (Wright et al. 2000).
The contribution of epiphytes to the abundance and species richness of canopy insects in a Mexican coffee plantation
Authors: Cruz-Angón Andrea , Baena Martha L. , Greenberg Russell
Published: July 2009

The abundance of epiphytes has been assumed to be important in explaining the high diversity of tropical canopy arthropods. In this study we assessed the possible role that the presence of epiphytes may have on the diversity and abundance of canopy insects in an experimental study conducted in a coffee plantation in Coatepec, Veracruz, Mexico. Epiphytes were removed from trees in one of two plots in two sites of the coffee plantation. In each plot we collected insects from threeInga jinicuiltrees by knockdown insecticide fogging. Insects were sorted to morphospecies, counted and measured. Trees with epiphytes had significantly higher numbers of species and individuals and insects larger than 5 mm were also more species-rich and abundant in trees with epiphytes. The magnitude of the enhancement was surprisingly large with the epiphyte plot samples having on average 90% more individuals and 22% more species than plots without epiphytes. These differences were even greater for large (>5 mm) insects (184% and 113% respectively). Our results support the tenet that epiphytes provide valuable resources to arthropods, which we have illustrated for canopy insects in shade trees of coffee plantations.
Introduction: The Laboratory of Nature – Science in the Mountains
Authors: Bigg Charlotte , Aubin David , Felsch Philipp
Published: July 2009

“Today I made the ascent of the highest mountain in this region, which for good reasons is called Ventosum, guided only by the desire to see the extraordinary altitude of the place” (Petrarque [1336] 1880, 6–7). Petrarch's ascent of the Mont Ventoux in 1336, or rather his account of it, established the mountain as a distinctive place for experiencing and understanding nature and self. Since then, the mountain has been sought out in increasing numbers by those pursuing spiritual elevation, bodily exertion, and/or scientific investigation. To this day, a pilgrimage church, several hotels, and an observatory are characteristically perched atop Mont Ventoux. And it is famous among cyclists as a legendarily difficultétapeof the Tour de France.
“To demonstrate the exactness of the instrument”: Mountainside Trials of Precision in Scotland, 1774
Authors: Reeves Nicky
Published: July 2009

Argument

The British Astronomer Royal, Nevil Maskelyne, spent four months on a Scottish mountainside in 1774, making observations of zenith stars and coordinating a detailed survey of the size and shape of the mountain Schiehallion, in order to demonstrate and quantify what was known as “the attraction of mountains.” His endeavors were celebrated in London, where it was stated that he had given proof of the universality of Newtonian gravitation and allowed for a calculation of the relative densities of the earth as a whole and the earth near its surface. This paper argues that the “Schiehallion Experiment” was as much a trial of the precision of Maskelyne's instruments and their expert management as it was a trial of Newtonian theory. By tracing the biography of the key instrument used by Maskelyne, his zenith sector, we see how much personal credibility was a stake for him in Scotland. By considering the mountainside as a place to test and reveal the precision of astronomical instruments we see a link between the Scottish endeavors and Maskelyne's ambitions for the Greenwich Observatory.
The Hotel that Became an Observatory: Mount Faulhorn as Singularity, Microcosm, and Macro-Tool
Authors: Aubin David
Published: July 2009

Argument

One of the first high-altitude observatories was a hotel. Established in 1823, the chalet on Mount Faulhorn became a highpoint of nineteenth-century science. In this paper, I take this mountain as my entry point into the examination of the special attraction that mountains exerted on scientists. I argue that Mount Faulhorn stood for three different conceptions of the usefulness of the mountain in science: (1) in observation networks, stations were usually chosen for pragmatic rather than scientific reasons, but mountains representedsingularspots in such networks, which deserved special attention; (2) the mountain also was amicrocosmwhere altitude differences were thought to capture essential features of latitude differences; (3) the mountain was sometimes no more than amacro-toolfor the pursuit of science, just a middle ground between the heaven and the earth.
Inherited Territories: The Glarus Alps, Knowledge Validation, and the Genealogical Organization of Nineteenth-Century Swiss Alpine Geognosy
Authors: Westermann Andrea
Published: July 2009

Argument

The article examines the organizational patterns of nineteenth-century Swiss Alpine geology. It argues that early and middle nineteenth-century Swiss geognosy was shaped in genealogical terms and that the patterns of genealogical reasoning and practice worked as a vehicle of transmission toward the generalization of locally gained empirical knowledge. The case study is provided by the Zurich geologist Albert Heim, who, in the early 1870s, blended intellectual and patrilineal genealogies that connected two generations of fathers and sons: Hans Conrad and Arnold Escher, Albert and Arnold Heim. Two things were transmitted from one generation to the next, a domain of geognostic research, the Glarus Alps, and a research interest in an explanation of the massive geognostic anomalies observed there. The legacy found its embodiment in the Escher family archive. The genealogical logic became visible and then experienced a crisis when, later in the century, the focus of Alpine geology shifted from geognosy to tectonics. Tectonic research loosened the traditional link between the intimate knowledge of a territory and the generalization from empirical data.
The Storm Lab: Meteorology in the Austrian Alps
Authors: Coen Deborah R.
Published: July 2009

Argument

What, if anything, uniquely defines the mountain as a “laboratory of nature”? Here, this question is considered from the perspective of meteorology. Mountains played a central role in the early history of modern meteorology. The first permanent year-round high-altitude weather stations were built in the 1880s but largely fell out of use by the turn of the twentieth century, not to be revived until the 1930s. This paper considers the unlikely survival of the Sonnblick observatory (3105 m.) in the Austrian Alps. By examining the arguments of the Sonnblick's critics and defenders, it reveals a seemingly paradoxical definition of the mountain as a space that simultaneously maximized isolation and communication. Drawing on the social and environmental history of the Alps, it shows how the Sonnblick came to appear as the perfect embodiment of this paradox.
The Elusive Placelessness of the Mont-Blanc Observatory (1893–1909): The Social Underpinnings of High-Altitude Observation
Authors: Le Gars Stéphane , Aubin David
Published: July 2009

Argument

From 1893 to 1909 when it definitely sunk into the glacier, the Mont-Blanc Observatory (MBO) struggled to find its scientific purpose. In this article, we use recent literature on the social characterization of place to analyze this struggle. Our first goal is to investigate where the observatory may fit in the laboratory-field dyad. We investigate various kinds of conceptual “borderlands” between these places and look at the networking activities between particular knowledge production sites. We argue that part observatory, part laboratory, and part field station, the place of the MBO was “heterotopic” space in Foucault's sense. We then examine the social underpinnings that led to the foundation of this observatory in the context of French Third Republic at the turn of the century. Following some of the ways the MBO was connected to other scientific sites and surveying some of its visitors' scientific practices, we finally hint at the fact that some of these practices played a part in the emergence of a regime of science production that endured into the twentieth century (astrophysical aeronautical practices, spatial stations, polar exploration, etc.)
Optimality in goal-dependent analysis of Sharing
Authors: AMATO GIANLUCA , SCOZZARI FRANCESCA
Published: July 2009

We face the problems of correctness, optimality, and precision for the static analysis of logic programs, using the theory of abstract interpretation. We propose a framework with a denotational, goal-dependent semantics equipped with two unification operators for forward unification (calling a procedure) and backward unification (returning from a procedure). The latter is implemented through a matching operation. Our proposal clarifies and unifies many different frameworks and ideas on static analysis of logic programming in a single, formal setting. On the abstract side, we focus on the domainsharingby Jacobs and Langen (The Journal of Logic Programming, 1992, vol. 13, nos. 2–3, pp. 291–314) and provide the best correct approximation of all the primitive semantic operators, namely, projection, renaming, and forward and backward unifications. We show that the abstract unification operators are strictly more precise than those in the literature defined over the same abstract domain. In some cases, our operators are more precise than those developed for more complex domains involving linearity and freeness.
THE PENDULUM SWINGS AGAIN: RECENT DEBATES ON CHINA'S PREWAR ECONOMY
Authors: Horesh Niv
Published: July 2009

The aim of this brief survey is to provide a critical review of studies of China's economic history recently published by prominent Western scholars. It will explore two veins of scholarly debates that underlie Western perceptions of both China's past and its trajectory of future development, and also consider the historic significance of joint-stock enterprise in China as opposed to Britain and Japan.
Energy budget of the reconnection process
Authors: Kiehas S. A. , Semenov V. S. , Biernat H. K.
Published: July 2009

The relevance of magnetic reconnection in the frame of space plasmas is mainly due to the energy conversion taking place during this process. We address our investigations within this article to the energy budget of the reconnection process and focus our research on the conversion of magnetic energy into kinetic plasma energy and the spatial redistribution of the energy density. Using a time‐dependent MHD reconnection model for an incompressible plasma, we derive the amount of released kinetic plasma energy and identify regions of enhanced an decreased magnetic field energy. The decrease of magnetic field energy in the wake of the outflowing plasma regions is compensated by a field energy enhancement above and below the outflow regions. This field energy is two times higher than the kinetic energy inside the plasma flow regions and gets removed from the reconnection site together with the plasma flow.
Climate response to large, high‐latitude and low‐latitude volcanic eruptions in the Community Climate System Model
Authors: Schneider David P. , Ammann Caspar M. , Otto‐Bliesner Bette L. , Kaufman Darrell S.
Published: July 2009

Explosive volcanism is known to be a leading natural cause of climate change. The second half of the 13th century was likely the most volcanically perturbed half‐century of the last 2000 years, although none of the major 13th century eruptions have been clearly attributed to specific volcanoes. This period was in general a time of transition from the relatively warm Medieval period to the colder Little Ice Age, but available proxy records are insufficient on their own to clearly assess whether this transition is associated with volcanism. This context motivates our investigation of the climate system sensitivity to high‐ and low‐latitude volcanism using the fully coupled NCAR Community Climate System Model (CCSM3). We evaluate two sets of ensemble simulations, each containing four volcanic pulses, with the first set representing them as a sequence of tropical eruptions and the second representing eruptions occurring in the mid‐high latitudes of both the Northern and Southern hemispheres. The short‐term, direct radiative impacts of tropical and high‐latitude eruptions include significant cooling over the continents in summer and cooling over regions of increased sea‐ice concentration in Northern Hemisphere (NH) winter. A main dynamical impact of moderate tropical eruptions is a winter warming pattern across northern Eurasia. Furthermore, both ensembles show significant reductions in global precipitation, especially in the summer monsoon regions. The most important long‐term impact is the cooling of the high‐latitude NH produced by multiple tropical eruptions, suggesting that positive feedbacks associated with ice and snow cover could lead to long‐term climate cooling in the Arctic.
Generation of plate‐like behavior and mantle heterogeneity from a spherical, viscoplastic convection model
Authors: Foley Bradford J. , Becker Thorsten W.
Published: July 2009

How plate tectonics arises from mantle convection is a question that has only very recently become feasible to address with spherical, viscoplastic computations. We present mainly internally heated convection results with temperature‐dependent viscosity and explore parts of the Rayleigh number (Ra)–yield stress (σy) phase space, as well as the effects of depth‐dependent σy, bottom heating, and a low‐viscosity asthenosphere. Convective planform and toroidal‐poloidal velocity field ratio (TPR) are affected by near‐surface viscosity variations, and TPR values are close to observed values for our most plate‐like models. At the relatively low convective vigor that is accessible at present, most models favor spherical harmonic degree one convection, though models with a weaker surface viscosity form degree two patterns and reproduce tomographically observed power spectra. An asthenospheric viscosity reduction improves plate‐like nature, as expected. For our incompressible computations, pure bottom heating produces strong plumes that tend to destroy plates at the surface. This implies that significant internal heating may be required, both to reduce the role of active upwellings and to form a low‐viscosity zone beneath the upper boundary layer.
Cosmic ray decreases affect atmospheric aerosols and clouds
Authors: Svensmark Henrik , Bondo Torsten , Svensmark Jacob
Published: July 2009

Close passages of coronal mass ejections from the sun are signaled at the Earth's surface by Forbush decreases in cosmic ray counts. We find that low clouds contain less liquid water following Forbush decreases, and for the most influential events the liquid water in the oceanic atmosphere can diminish by as much as 7%. Cloud water content as gauged by the Special Sensor Microwave/Imager (SSM/I) reaches a minimum ≈7 days after the Forbush minimum in cosmic rays, and so does the fraction of low clouds seen by the Moderate Resolution Imaging Spectroradiometer (MODIS) and in the International Satellite Cloud Climate Project (ISCCP). Parallel observations by the aerosol robotic network AERONET reveal falls in the relative abundance of fine aerosol particles which, in normal circumstances, could have evolved into cloud condensation nuclei. Thus a link between the sun, cosmic rays, aerosols, and liquid‐water clouds appears to exist on a global scale.
Determining azimuthal variations in frontal Froude number from SAR imagery
Authors: Pan Jiayi , Jay David A. , Lin Hui
Published: July 2009

River plume fronts are the locus of strong mixing between plume and ambient coastal waters, contribute to coastal productivity, and exert a major impact on coastal ecosystems. The frontal Froude number Fr is an important parameter characterizing the frontal status with respect to both propagation and vertical mixing. In this study, we examine azimuthal variations in Fr using a new remote sensing method. We derive Fr from SAR image data on the basis of the SAR imaging theory and the mechanism of internal wave fission at front. This method is applied to a SAR image showing a front off the Columbia River (CR) mouth taken on 31 May 2003 at 14:33:19 UTC under weak wind conditions. Fr increases from south to north along the front. This variation is consistent with potential vorticity conservation and the influence of tidal currents on the plume. This calculation confirms arguments based on vessel observations by Jay et al. (2009).
Impact of the Madden Julian Oscillation on tropical storms and risk of landfall in the ECMWF forecast system
Authors: Vitart F.
Published: July 2009

Using a series of 46‐days hindcasts, this paper shows that the Madden Julian Oscillation (MJO) has a significant impact on the statistics of tropical storms generated by a dynamical model. This impact is generally consistent with observations. In particular the risk of landfall over Australia and North America varies significantly with the phases of the MJO, as observed. This suggests that sub‐seasonal prediction of the risk of tropical storm landfall should be possible with a dynamical model such as the one used in this study, which has skill in predicting the evolution of the MJO up to 20 days.
Characterizing land surface processes: A quantitative analysis using air‐ground thermal orbits
Authors: Smerdon Jason E. , Beltrami Hugo , Creelman Chance , Stevens M. Bruce
Published: July 2009

A quantitative analysis of thermal orbits is developed and applied to modeled air and ground temperatures. Thermal orbits are phase‐space representations of air and ground temperature relationships that are generated by plotting daily or monthly ground temperatures against air temperatures. Thermal orbits are useful descriptive tools that provide straightforward illustrations of air and ground temperature relationships in the presence of land surface processes related to snow cover, soil freezing, and vegetation effects. The utility of thermal orbits has been limited, however, by the lack of quantitative analyses that describe changes in orbits across different environments or in time. This shortcoming is overcome in the present study by developing a linear regression analysis of thermal orbits that allows changes to be tracked in time and space and as a function of depth within the subsurface. The theory that underlies the thermal orbit regression analysis is developed herein, and the utility of the application is demonstrated using controlled model experiments.