bluuebunny/crossref_metadata_2025 huggingface dataset:
A combinatorial genetic library approach to target heterologous glycosylation enzymes to the endoplasmic reticulum or the Golgi apparatus of Pichia pastoris
Authors: Nett Juergen H. , Stadheim Terrance A. , Li Huijuan , Bobrowicz Piotr , Hamilton Stephen R. , Davidson Robert C. , Choi Byung‐Kwon , Mitchell Teresa , Bobrowicz Beata , Rittenhour Alissa , Wildt Stefan , Gerngross Tillman U.
Published: November 2010

To humanize the glycosylation pathway in the yeast Pichia pastoris, we developed several combinatorial genetic libraries and used them to properly localize active eukaryotic mannosidases and sugar transferases. Here we report the details of the fusion of up to 66 N‐terminal targeting sequences of fungal type II membrane proteins to 33 catalytic domains of heterologous glycosylation enzymes. We show that while it is difficult to predict which leader/catalytic domain will result in the desired activity, analysis of the fusion protein libraries allows for the selection of the leader/catalytic domain combinations that function properly. This combinatorial approach, together with a high‐throughput screening protocol, has allowed us to humanize the yeast glycosylation pathway to secrete human glycoprotein with complex N‐glycosylation. Copyright © 2011 John Wiley & Sons, Ltd.
Female nile hippopotamus (Hippopotamus amphibius) space use in a naturalistic exhibit
Authors: Blowers Tracy E. , Waterman Jane M. , Kuhar Christopher W. , Bettinger Tammie L.
Published: November 2010

Zoological institutions provide naturalistic exhibits for their animals in order to offer a more appealing look for visitors and give the animal the opportunity to engage in more natural behaviors. Examining space use of the animals in the naturalistic exhibit may aid in the management of these animals and inform future naturalistic exhibit design. The hippopotamus is an amphibious ungulate that spends much of its days in the wild in the water but may be found along the banks of the rivers basking in the sun. Our objective was to determine how captive female hippos utilize their exhibit by examining whether hippos selected for certain areas of a naturalistic exhibit. Scan sample data were collected on a group of nine captive female hippos housed at Disney's Animal Kingdom®. Using ArcView, the data were analyzed to determine distribution of hippos in the exhibit and their utilization of depth categories while in the water. Hippos were found to aggregate in preferred areas of the exhibit, mostly water, and selected most for water depths of 0.6–1.0 m. These results will aid in the understanding of hippopotamus space use and may aid zoological institutions in the design of naturalistic exhibits for hippos. Zoo Biol 31: 129–136, 2012. © 2010 Wiley Periodicals, Inc.
Learning and relearning effects with innovative service designs: An empirical analysis of top golf courses
Authors: Heim Gregory R. , Ketzenberg Michael E.
Published: November 2010

This paper examines learning and relearning effects for initial service designs and later service redesigns. We analyze an experience‐based service where external design firms typically perform service design and implementation tasks, while local service personnel manage daily operations. We examine whether the quality of service during routine operation periods exhibits learning effect patterns. We also examine window of opportunity effects after major redesigns. Examining yearly data on top Texas golf courses, we observe learning across the lifespan of golf courses and relearning after golf course redesigns. The findings contribute to the literature on learning and experience‐based services. The study provides managerial insight by demonstrating the extent of learning, illustrating how redesigns can affect service outcomes negatively, showing how relearning occurs, and discussing tactics for success when redesigning services.
Correlation of pepsin‐measured laryngopharyngeal reflux disease with symptoms and signs
Authors: Wang Lu , Liu Xiong , Liu You‐li , Zeng Fang‐fang , Wu Ting , Yang Chun‐li , Shen Hai‐yan , Li Xiang‐ping
Published: November 2010

OBJECTIVE

Pepsin detection in throat sputum has been posited as a reliable biological marker of laryngopharyngeal reflux disease (LPRD). This study was designed to further correlate pepsin concentration with symptoms and signs of LPRD.

STUDY DESIGN

Cross‐sectional study.

SETTING

Nanfang Hospital of Southern Medical University.

SUBJECTS AND METHODS

Fifty‐six laryngitis patients were divided into a reflux laryngitis group and a chronic laryngitis group based on the reflux symptom index (RSI), reflux finding score (RFS), and proton pump inhibitor treatment for two weeks. Oral and hypopharyngeal secretions from the study patients and from 15 healthy subjects were collected. Thirty‐six obstructive sleep apnea (OSA) patients were divided into a mild‐moderate group and a severe group by the apnea‐hypopnea index (AHI). Bedtime and first‐morning oral secretions were collected. Enzyme‐linked immunosorbent assay was used to measure the pepsin concentration.

RESULTS

In laryngitis patients, the total score of RSI and RFS (P < 0.05), and the symptoms, including clearing throat often, coughing, and sensing a lump in the throat (P < 0.006), were more severe in the pepsin‐positive group. No significant differences were found between the oral and hypopharyngeal secretions. In OSA, pepsin levels in the first‐morning oral secretions were correlated with AHI, mean SaO2, and mini SaO2 (P < 0.01). However, RSIs were not significantly correlated with these indicators.

CONCLUSION

Higher levels of pepsin in sputum were associated with higher RSI and RFS in cases of laryngitis. There was no relationship between pepsin levels and RSI in cases of OSA. There were no differences of pepsin concentration in sputum collection methods or in collection timing.
How does reflux affect laryngeal tissue quality? An experimental and histopathologic animal study
Authors: Habesoglu Mehmet , Habesoglu Tulay Erden , Gunes Pembegul , Kinis Vefa , Toros Sema Zer , Eriman Murat , Egeli Erol
Published: November 2010

OBJECTIVE

To investigate the histopathologic changes in intact laryngeal epithelium and mucosa exposed to endogenous gastric acid and pepsin in an experimental model of reflux.

STUDY DESIGN

Randomized trial.

SETTING

The study was conducted at the animal care facility of Haydarpasa Numune Education and Research Hospital.

SUBJECTS AND METHODS

Eighteen healthy 200‐ to 220‐g, 20‐week‐old Sprague‐Dawley rats were used. The animals were divided into three groups according to exposure time (1‐, 4‐, and 12‐week exposures), and four rats were examined as controls who underwent sham operation. An experimental model of gastroesophageal reflux was induced. After exposure, the animals were euthanized, and their larynges were removed. The histopathologic changes in the larynx were observed under a light microscope.

RESULTS

The mean scores for inflammation in the control, one‐, four‐, and 12‐week groups were 0.75 ± 0.50, 1.75 ± 0.50, 2.20 ± 0.45, and 1.94 ± 0.87, respectively. However, mean scores for vascular engorgement in the control, one‐, and four‐week groups were 0, and in the 12‐week group was 2.0 ± 0.70. The mean scores for subepithelial edema in the control, one‐, four‐, and 12‐week groups were 1.00 ± 0, 1.75 ± 0.95, 1.80 ± 0.45, and 2.20 ± 0.84, respectively. However, mean scores for keratinization for the control, one‐, and four‐week groups were 0, and for the 12‐week group was 1.60 ± 0.55. When we compared inflammation, vascular engorgement, subepithelial edema, and keratinization mean scores between the control and study groups, there were statistically significant increases (P = 0.005, P = 0.001, P = 0.043, P = 0.002, respectively).

CONCLUSION

Our findings suggest that reflux induces significant histopathologic changes in larynx mucosa.
Correlation of biomarkers in head and neck squamous cell carcinoma
Authors: Tse Gary M. , King Ann D. , Yu Alex M. C. , Lam Christopher C. F. , Chan Anthony W. H. , Chen George G. , Yeung David K. , Yu Kwok‐Hung , Bhatia Kunwar S. , Chan Amy B. W.
Published: November 2010

OBJECTIVE

To evaluate the relationship of functional magnetic resonance imaging (MRI) parameters, including choline/creatine ratio (Cho/Cr) and apparent diffusion coefficient (ADC) with protein expression of 10 common tumor and prognostic markers in head and neck squamous cell carcinoma.

STUDY DESIGN

Cross‐sectional study.

SETTING

University hospital.

SUBJECTS AND METHODS

The Cho/Cr and ADC obtained from 74 patients with head and neck squamous cell carcinoma were correlated with the expression level of the 10 protein markers as determined by immunohistochemistry.

RESULTS

Cho/Cr showed significant positive correlations with cyclooxygenase 2 in primary tumors (r = 0.714), and epidermal growth factor receptor in metastatic cervical lymph nodes (r = 0.522). ADC showed significant (r = −0.591) negative correlation with human epidermal growth factor receptor 2 in metastatic cervical lymph nodes.

CONCLUSION

There are relationships between protein and functional MRI markers. Future research in this direction may improve our understanding of the cancer micro‐environment.
Associations of dietary dark-green and deep-yellow vegetables and fruits with cervical intraepithelial neoplasia: modification by smoking
Authors: Tomita Luciana Y. , Roteli-Martins Cecília M. , Villa Luisa L. , Franco Eduardo L. , Cardoso Marly A.
Published: November 2010

Smoking has been positively and fruit and vegetable intake has been negatively associated with cervical cancer, the second most common cancer among women worldwide. However, a lower consumption of fruits and reduced serum carotenoids have been observed among smokers. It is not known whether the smoking effect on the risk of cervical neoplasia is modified by a low intake of fruits and vegetables. The present study examined the combined effects of tobacco smoking and diet using a validated FFQ and serum carotenoid and tocopherol levels on cervical intraepithelial neoplasia grade 3 (CIN3) risk in a hospital-based case–control study conducted in São Paulo, Brazil, between 2003 and 2005. The sample comprised 231 incident, histologically confirmed cases of CIN3 and 453 controls. A low intake ( ≤ 39 g) of dark-green and deep-yellow vegetables and fruits without tobacco smoking had a lesser effect on CIN3 (OR 1·14; 95 % CI 0·49, 2·65) than among smokers with higher intake ( ≥ 40 g; OR 1·83; 95 % CI 0·73, 4·62) after adjusting for confounders. The OR for the joint exposure of tobacco smoking and low intake of vegetables and fruits was greater (3·86; 95 % CI 1·74, 8·57; P for trend < 0·001) compared with non-smokers with higher intake after adjusting for confounding variables and human papillomavirus status. Similar results were observed for total fruit, serum total carotene (including β-, α- and γ-carotene) and tocopherols. These findings suggest that the effect of nutritional factors on CIN3 is modified by smoking.
Development of specific ITS markers for plant DNA identification within herbivorous insects
Authors: Pumariño L. , Alomar O. , Agustí N.
Published: November 2010

DNA-based techniques have proved to be very useful methods to study trophic relationships between pests and their natural enemies. However, most predators are best defined as omnivores, and the identification of plant-specific DNA should also allow the identification of the plant species the predators have been feeding on. In this study, a PCR approach based on the development of specific primers was developed as a self-marking technique to detect plant DNA within the gut of one heteropteran omnivorous predator (Macrolophus pygmaeus) and two lepidopteran pest species (Helicoverpa armigera and Tuta absoluta). Specific tomato primers were designed from the ITS 1–2 region, which allowed the amplification of a tomato DNA fragment of 332 bp within the three insect species tested in all cases (100% of detection at t=0) and did not detect DNA of other plants nor of the starved insects. Plant DNA half-lives at 25°C ranged from 5.8 h, to 27.7 h and 28.7 h within M. pygmaeus, H. armigera and T. absoluta, respectively. Tomato DNA detection within field-collected M. pygmaeus suggests dietary mixing in this omnivorous predator and showed a higher detection of tomato DNA in females and nymphs than males. This study provides a useful tool to detect and to identify plant food sources of arthropods and to evaluate crop colonization from surrounding vegetation in conservation biological control programs.
Resynthesized lines and cultivars ofBrassica napusL. provide sources of resistance to the cabbage stem weevil (Ceutorhynchus pallidactylus(Mrsh.))
Authors: Eickermann M. , Ulber B. , Vidal S.
Published: November 2010

The cabbage stem weevil (Ceutorhynchus pallidactylus(Mrsh.)) (Col., Curculionidae) is a serious pest of winter oilseed rape (Brassica napusL.var. oleiferaMetzg.) in central and northern Europe. Although host-plant resistance is a key tool in integrated pest management systems, resistant genotypes are not yet available for this species. Resynthesized rapeseed lines (B. oleraceaL.×B. rapaL.) are broadening the genetic diversity and might have potential as sources of resistance to pest insects. The host quality, of nine resynthesized rapeseed lines and six genotypes ofB. napusto cabbage stem weevil, was evaluated in laboratory screening tests and in a semi-field experiment. In dual-choice oviposition tests, femaleC. pallidactyluslaid significantly fewer eggs on five resyntheses and on swede cv ‘Devon Champion’ than on the moderately susceptible oilseed rape cv ‘Express’, indicating a lower host quality of these genotypes. Results of laboratory screenings were confirmed in a semi-field experiment, in which twelve genotypes were exposed toC. pallidactylusfemales. The number of larvae was significantly lower in two resyntheses and in cv ‘Devon Champion’ than in oilseed rape cv WVB 9. The total, as well as individual, glucosinolate (GSL) content in the leaves differed substantially among the genotypes tested. The amount of feeding by larvae ofC. pallidactylus, as measured by a stem-injury coefficient, was positively correlated with the indolyl GSL compounds 3-indolylmethyl and 4-methoxy-3-indolylmethyl, and with the aromatic GSL 2-phenylethyl, whereas it was negatively correlated with 4-hydroxy-3-indolylmethyl. Thus, the composition and concentration of GSL compounds within the plant tissue might be a key factor in breeding for pest resistance in oilseed rape.
U–Pb SHRIMP ages of detrital granulite-facies rutiles: further constraints on provenance of Jurassic sandstones on the Norwegian margin
Authors: MEINHOLD GUIDO , MORTON ANDREW C. , FANNING C. MARK , WHITHAM ANDREW G.
Published: November 2010

Electron microprobe analyses of 128 detrital rutile grains from two Jurassic sandstone samples (Hettangian and Bajocian–Bathonian in age) from hydrocarbon exploration wells on the Norwegian margin confirm that more than 85 % of the rutiles were derived from metapelitic rocks. Zr-in-rutile geothermometry confirms that about 83 % of the rutile was formed under high-grade metamorphism (>750 °C). Sixty-two rutile grains, including 60 of the identified high-temperature rutile population, were also analysed for U–Pb geochronology using SHRIMP. The 206Pb–238U rutile ages range from approximately 485–292 Ma, with a major cluster between 450 and 380 Ma. These data suggest that the detrital rutile was predominantly derived from a felsic source that experienced granulite-facies metamorphism about 450–380 Ma ago. This conclusion is consistent with derivation from high-grade Caledonian metasedimentary rocks, probably the Krummedal sequence in central East Greenland, as previously suggested by an earlier provenance study using conventional heavy mineral analysis, garnet geochemistry and detrital zircon age dating. The present study underscores the importance of rutile geochemistry and geochronology in quantitative single-mineral provenance analysis of clastic sedimentary rocks.
40th Anniversary ofJIPA
Authors: Esling John H.
Published: November 2010

This year, 2010, we celebrate the 40th anniversary of the publication of the Journal of the International Phonetic Association and the 125th anniversary of the publishing of a journal by the Association. From 1886 through 1888, the journal had the title The Phonetic Teacher, rendered variably as Dhi Fonètik Tîtcer (1886–1887), dhə fənetik tîtcər (1887–1888), ðə fonetik tîtcər (1888). From 1889 to 1970, the name of the journal was Le Maître Phonétique (lə mɛːtr fɔnetik, revised in 1895 to lə mɛːtrə fɔnetik) in which articles and letters were usually published in phonetic transcription; hence, the journal is traditionally referred to as the ‘mf’.
Sample articles from Le Maître Phonétique
Authors: Hirst Daniel
Published: November 2010

The following two texts were published by the predecessor of our journal over half a century ago and illustrate the characteristic nature of its publications at that time.
Slovak
Authors: Hanulíková Adriana , Hamann Silke
Published: November 2010

Slovak (sometimes also called Slovakian) is an Indo-European language belonging to the West-Slavic branch, and is most closely related to Czech. Slovak is spoken as a native language by 4.6 million speakers in Slovakia (that is by roughly 85% of the population), and by over two million Slovaks living abroad, most of them in the USA, the Czech Republic, Hungary, Canada and Great Britain (Office for Slovaks Living Abroad 2009).
Prelude to the Principles of 1949
Authors: MacMahon Michael K. C.
Published: November 2010

‘In choosing between the various proposals that have been made for revising our alphabet, we've been guided by the following principles, which I think are admitted by most of our readers as essential to a practical system of phonetic spelling.’ (Passy 1888: 57)
IPA NEWS
Authors: Engstrand Olle , Granström Björn , Lindblom Björn , Strangert Eva
Published: November 2010

The 17th International Congress of Phonetic Sciences (ICPhS XVII) will take place in Hong Kong, China, at the Hong Kong Convention and Exhibition Centre, on 17–21 August 2011. ICPhS XVII is organized jointly by the City University of Hong Kong, the Chinese Academy of Social Sciences, Beijing, and the Academia Sinica, Taipei, under the auspices of the Permanent Council for the Organization of the International Congresses of Phonetic Sciences and the International Phonetic Association. The deadline for full-paper submission to ICPhS 2011 Hong Kong is 1 March 2011. Further information is available at http://www.icphs2011.hk.
Deep seaYoldiella(Pelecypoda: Protobranchia: Yoldiidae) from Campos Basin, Rio de Janeiro, Brazil
Authors: Benaim Natalia Pereira , Absalão Ricardo Silva
Published: November 2010

Despite the increasing number of reports on the deep-sea molluscs from the south-western Atlantic, we know very little about the protobranchs. The lack of information on the protobranch Pelecypoda off southern Brazil is reflected in the genusYoldiella. This contribution is part of an effort to increase the knowledge about this group off the Brazilian coast. Eight species ofYoldiellaare recognized here. ForYoldiella biguttata, previously reported from Brazil, the known distribution is extended southwards to the Campos Basin. ForYoldiella similisthis is the first record in the western Atlantic Ocean. ForYoldiella extensaandYoldiellaaff.jeffreysithis is the first record for Brazil. Four previously unknown species are described,Yoldiella lapernoisp. nov.,Yoldiella paranapuaensissp. nov.,Yoldiella arariboiasp. nov. andYoldiella curupirasp. nov. Considering only conchological features for the Atlantic species we could propose some clusters of species ofYoldiella.
Radio Positioning using the Digital Audio Broadcasting (DAB) Signal
Authors: Palmer Duncan , Moore Terry , Hill Chris , Andreotti Marcus , Park David
Published: November 2010

Over the recent decades, there have been a number of trends that have driven the desire to improve the ability to position and navigate in all environments. While GPS has been the driving factor behind most of these trends, there are limitations to GPS that have become more evident over time as the World has increasingly come to rely on location. These limitations are mostly due to the low transmission power of GPS satellites, where navigation signals broadcast from space are comparatively weak, especially by the time they have travelled to receivers on the ground. This makes the signals particularly vulnerable to fading in difficult environments such as built-up urban areas. The low signal-to-noise ratio (SNR) also means that the signals are susceptible to jamming, both hostile and accidental.

This motivates the need for non-GPS (or, more generally, non-GNSS) navigation technologies, for example, terrestrial based alternatives to GNSS such as eLoran. But, there is also significant interest in the exploitation of other non-navigation signals for positioning and navigation purposes. These so-called ‘Signals of Opportunity’ (SoOP) do not generally require any alterations to existing communications transmission infrastructure and often use alternative multi-carrier modulation techniques to those methods used by most GNSS services. The major challenge of using a SoOP for location purposes is that the transmitter network infrastructure has not generally been designed with positioning as a requirement.

An ongoing project, at the Institute of Engineering Surveying and Space Geodesy (IESSG) of the University of Nottingham, is directed towards an investigation of the potential of the Digital Audio Broadcast (DAB) signal for positioning purposes. A prototype Software Defined Radio (SDR) DAB positioning receiver has been developed and has now been tested. This paper presents a detailed review of the structure of the DAB signals and explains how these signals can be used as the basis of a positioning system. In addition the development of the prototype SDR receiver and the initial results are presented and discussed.
The Global Hawk/BAMS Navigation System; an Update to the Odyssey…
Authors: Loegering Greg S.
Published: November 2010

Over 10 years ago, a paper was published at the ION-GPS ‘99 conference that detailed the design of the navigation system implemented on the Global Hawk UAS program then being run under the auspices of DARPA. Since that time, many changes have occurred in the program including transition from DARPA to USAF management, the development of the larger Block 20/30 unmanned aircraft (UA) and the awarding of the Broad Area Maritime Surveillance (BAMS) program to Northrop Grumman which is based on the Global Hawk Block 20/30 aircraft. In addition, many changes have been made to the aircraft navigation system as well as many lessons learned on the kind of navigation system required to support a long endurance UA. The result has been a much more robust set of navigation sensors that allows this aircraft to successfully support the efforts to counter terrorism in the world today.1
Remotely Piloted Air Systems on Trial and in Operations
Authors: Southcott Gary
Published: November 2010

The aim of the paper is to inform design staffs on potential Remotely Piloted Air Systems (RPAS) improvements to afford greater utility on the battlespace. The scope of the paper covers Air Warfare Centre experiences working with several NATO Class II RPAS. Using an ‘assurance framework’ that examines integrity of the aircraft, the operational environment and crew competency, the paper identifies what changes need to be made if the utility of RPAS in this category is to be enhanced.
La phonologie parisienne à trente ans d'intervalle – Les voyelles à double timbre
Authors: HANSEN ANITA BERIT , JUILLARD CAROLINE
Published: November 2010

En français parisien, on parle depuis quelques décennies déjà d'un changement affectant le système des voyelles dites ‘à double timbre’. Ces voyelles comptent quatre paires (/e/-/ɛ/ comme dans parlé-parlait, /ø/-/œ/ comme dans jeûne-jeune, /o/-/ɔ/ comme dans saute-sotte et /ɑ/-/a/ comme dans mâle-mal). La différence interne dans chaque paire peut s'exprimer comme une distance physique plus ou moins grande sur le lieu d'articulation, les autres traits restant constants (différence d'aperture pour les trois premières, différence en termes de postériorisation de la racine de la langue vers le pharynx pour la dernière), ce qui explique partiellement pourquoi elles sont souvent réunies dans les descriptions traditionnelles du français standard: elles consistent toutes d'une voyelle avec un timbre fermé et d'une voyelle avec un timbre ouvert. Elles partagent, en outre, certains principes de distribution allophonique dans les cas où elles ne forment pas de paires minimales (par exemple pour /Ø/, /O/: uniquement le timbre fermé en finale absolue). Depuis l'enquête de Martinet en 1941, qui avait la forme d'une auto-évaluation de la part de 250 informateurs adultes de Paris et de la France du Nord (questions du type: ‘Prononcez-vous de façon identique pâte et patte ?’, Martinet, 1945 [1971]), et les enquêtes successives à méthodologie semblable de Reichstein (1960) (sur 556 élèves, âgées de 13 à 15 ans) et de Deyhime (1967a, b) (sur 500 étudiants de la Cité Universitaire à Paris), nous avons des preuves que de moins en moins de Parisiens font la distinction entre les deux /A/. Martinet (1969) a fait la synthèse de ces trois enquêtes. D'autres études, se servant d'analyses phonétiques auditives, ont confirmé ceci et ont élargi l'observation: les /E/ sont également touchés. Dans leurs enquêtes parisiennes, Léon (1973), Peretz (1977a), Peretz-Juillard (1985) et Landick (1995) ont noté des timbres intermédiaires là où on s'attendrait à une distinction entre timbre fermé, /e/, et timbre ouvert, /ɛ/. Les deux dernières paires de voyelles sont probablement concernées aussi, mais à un moindre degré: selon le témoignage de Landick (1995), basé sur des données de la fin des années 1980, l'opposition des deux /Ø/ n'est stable que parmi les locuteurs ayant fait des études supérieures, et l'opposition des deux /O/ est entamée aussi, mais reste la plus forte des quatre.
Modeling of craton stability using a viscoelastic rheology
Authors: Beuchert Marcus J. , Podladchikov Yuri Y. , Simon Nina S. C. , Rüpke Lars H.
Published: November 2010

Archean cratons belong to the most remarkable features of our planet since they represent continental crust that has avoided reworking for several billions of years. Even more, it has become evident from both geophysical and petrological studies that cratons exhibit deep lithospheric keels which equally remained stable ever since the formation of the cratons in the Archean. Dating of inclusions in diamonds from kimberlite pipes gives Archean ages, suggesting that the Archean lithosphere must have been cold soon after its formation in the Archean (in order to allow for the existence of diamonds) and must have stayed in that state ever since. Yet, although strong evidence for the thermal stability of Archean cratonic lithosphere for billions of years is provided by diamond dating, the long‐term thermal stability of cratonic keels was questioned on the basis of numerical modeling results. We devised a viscoelastic mantle convection model for exploring cratonic stability in the stagnant lid regime. Our modeling results indicate that within the limitations of the stagnant lid approach, the application of a sufficiently high temperature‐dependent viscosity ratio can provide for thermal craton stability for billions of years. The comparison between simulations with viscous and viscoelastic rheology indicates no significant influence of elasticity on craton stability. Yet, a viscoelastic rheology provides a physical transition from viscously to elastically dominated regimes within the keel, thus rendering introduction of arbitrary viscosity cutoffs, as employed in viscous models, unnecessary.
Interaction between mantle and crustal detachments: A nonlinear system controlling lithospheric extension
Authors: Rosenbaum Gideon , Regenauer‐Lieb Klaus , Weinberg Roberto F.
Published: November 2010

We use numerical modeling to investigate the development of crustal and mantle detachments during lithospheric extension. Our models simulate a wide range of extensional systems with varying values of crustal thickness and heat flow, showing how strain localization in the mantle interacts with localization in the upper crust and controls the evolution of extensional systems. Model results reveal a richness of structures and deformation styles as a response to a self‐organized mechanism that minimizes the internal stored energy of the system by localizing deformation. Crustal detachments, here referred as low‐angle normal decoupling horizons, are well developed during extension of overthickened (60 km) continental crust, even when the initial heat flow is relatively low (50 mW m−2). In contrast, localized mantle deformation is most pronounced when the extended lithosphere has a normal crustal thickness (30–40 km) and an intermediate heat flow (60–70 mW m−2). Results show a nonlinear response to subtle changes in crustal thickness or heat flow, characterized by abrupt and sometimes unexpected switches in extension modes (e.g., from diffuse extensional deformation to effective lithospheric‐scale rupturing) or from mantle‐ to crust‐dominated strain localization. We interpret this nonlinearity to result from the interference of doming wavelengths in the presence of multiple necking instabilities. Disharmonic crust and mantle doming wavelengths results in efficient communication between shear zones at different lithospheric levels, leading to rupturing of the whole lithosphere. In contrast, harmonic crust and mantle doming inhibits interaction of shear zones across the lithosphere and results in a prolonged history of extension prior to continental breakup.
Moho map of South America from receiver functions and surface waves
Authors: Lloyd Simon , van der Lee Suzan , França George Sand , Assumpção Marcelo , Feng Mei
Published: November 2010

We estimate crustal structure and thickness of South America north of roughly 40°S. To this end, we analyzed receiver functions from 20 relatively new temporary broadband seismic stations deployed across eastern Brazil. In the analysis we include teleseismic and some regional events, particularly for stations that recorded few suitable earthquakes. We first estimate crustal thickness and average Poisson's ratio using two different stacking methods. We then combine the new crustal constraints with results from previous receiver function studies. To interpolate the crustal thickness between the station locations, we jointly invert these Moho point constraints, Rayleigh wave group velocities, and regional S and Rayleigh waveforms for a continuous map of Moho depth. The new tomographic Moho map suggests that Moho depth and Moho relief vary slightly with age within the Precambrian crust. Whether or not a positive correlation between crustal thickness and geologic age is derived from the pre‐interpolation point constraints depends strongly on the selected subset of receiver functions. This implies that using only pre‐interpolation point constraints (receiver functions) inadequately samples the spatial variation in geologic age. The new Moho map also reveals an anomalously deep Moho beneath the oldest core of the Amazonian Craton.
Early Holocene and Late Pleistocene slip rates of the southern Dead Sea Fault determined from 10Be cosmogenic dating of offset alluvial deposits
Authors: Le Béon Maryline , Klinger Yann , Al‐Qaryouti Mahmoud , Mériaux Anne‐Sophie , Finkel Robert C. , Elias Ata , Mayyas Omar , Ryerson Frederick J. , Tapponnier Paul
Published: November 2010

Two sites located along the Wadi Araba Fault (WAF) segment of the Dead Sea Fault are targeted for tectonic‐morphological analysis. 10Be cosmogenic radionuclide (CRN) dating of embedded cobbles is used to constrain the age of offset alluvial surfaces. At the first site a 48 ± 7 m offset alluvial fan, for which 10Be CRN model ages average 11.1 ± 4.3 ka, yield a slip rate of 5.4 ± 2.7 mm/a, with conservative bounds of 1.3–16.4 mm/a. At the second site the scattered distributions of the 10Be CRN ages from an offset bajada attest to the complex processes involved in sediment transport and emplacement. There, two offsets were identified. The 160 ± 8 m offset of an incised alluvial fan dated at 37 ± 5 ka shows a slip rate of 4.5 ± 0.9 mm/a, with a conservative minimum value of 3.2 mm/a. A larger offset, 626 ± 37 m, is derived from a prominent channel incised into the bajada. Cobbles from the bajada surface have ages from 33 to 141 ka, with a mean of 87 ± 26 ka. A slip rate of 8.1 ± 2.9 mm/a is derived from the mean age, with conservative bounds of 3.8–22.1 mm/a. These results and other published slip rates along the linear WAF segment, from GPS to geological time scales, lack the resolution to fully resolve the question of temporal variations versus consistency of the fault slip rate of the WAF. Yet, given the uncertainties, they are not inconsistent with each other.
Response of buoyant plumes to transient discharges investigated using an adaptive solver
Authors: O'Callaghan J. , Rickard G. , Popinet S. , Stevens C.
Published: November 2010

The behavior of buoyant plumes driven by variable momentum inputs were examined using an adaptive Navier‐Stokes solver (Gerris). Boundary conditions were representative of an idealized stratified, coastal environment. Salinity ranged from 5 to 30 in the top 5 m of the water column to replicate the strong vertical gradients experienced in fjord environments. Two‐dimensional simulations examined the response of the buoyant plume driven by zero, steady, and variable momentum fluxes. The behavior was quantified in terms of the characteristic features of a buoyant plume, the thickness of the nose (or head of gravity current), and the trailing tail. Both the nose and tail of the plume were substantially thicker for the variable momentum run, whereas elongation and thinning of the plume was evident for the steady and zero momentum inputs. Furthermore, an order of magnitude difference in available potential energy was found for the variable momentum run. Validation of the Boussinesq approximation initially utilized the classic lock‐exchange experiment with excellent agreement to previous numerical and theoretical experiments. Frontal speeds of the gravity current converged toward the theoretical value of Benjamin (1968). The adaptive mesh permitted lock‐exchange simulations at Reynolds number (Re) of ∼10,500 and are some of the highest Re runs to date. Moreover, improved computational efficiency was achieved using the adaptive solver with simulations completed in 20% of the time they took on a static, high‐resolution grid.
Source identification of aerosols influencing atmospheric extinction: Integrating PMF and PSCF with emission inventories and satellite observations
Authors: Cherian R. , Venkataraman C. , Kumar A. , Sarin M. M. , Sudheer A. K. , Ramachandran S.
Published: November 2010

The relative influence of source categories of aerosols that affect atmospheric extinction is analyzed by evaluating the potential source contribution function (PSCF) based source regions of the positive matrix factorization (PMF) estimated factors against satellite retrievals of aerosol index and active fires and combining with emission inventory information. This approach has been applied to aerosol chemical data obtained from the integrated campaign undertaken during March–May 2006: Integrated Campaign for Aerosols, Gases and Radiation Budget (ICARB). Four source categories were identified: dust, nitrate‐and‐dust, biomass‐and‐fossil combustion, and secondary species. The relative influence of dust and nitrate‐and‐dust was higher during north–south transport from west Asia over the Arabian Sea during the period of campaign, coincident with highs in the spatial distribution of Ultraviolet Aerosol Index (UVAI) from the Ozone Monitoring Instrument (OMI), implying dust‐nitrate association in the outflow from west Asia. The relative influence of anthropogenic sources (biomass‐and‐fossil combustion and secondary species) was higher over Bay of Bengal during March–April 2006. High fire frequency from the Moderate Resolution Imaging Spectroradiometer (MODIS), coincident with the probable source regions identified in the central Indo‐Gangetic plain and central India (south of 27°N), indicates influence of biomass burning source. The biomass‐and‐fossil combustion factor arising from biofuel, crop residue, and forest fires is evident by their large emission flux rather than from industrial sources in the probable source regions associated with this factor. In contrast, thermal power plant and industries largely influenced the secondary species factor. This approach provides verification of source categories identified through PMF against active sources from satellite remote sensing and provides an estimate of their relative strength based on emission inventory information.
Low‐frequency noise in δ13C and δ18O tree ring data: A case study of Pinus uncinata in the Spanish Pyrenees
Authors: Esper Jan , Frank David C. , Battipaglia Giovanna , Büntgen Ulf , Holert Christopher , Treydte Kerstin , Siegwolf Rolf , Saurer Matthias
Published: November 2010

Isotopic discrimination measurements in tree rings are becoming increasingly important estimators of past environmental change. Potential biases inherent to these parameters, including age trend and level offset are, however, not well understood. We here perform measurements on a new millennium‐long data set of decadally resolved δ18O and δ13C discrimination from 25 high‐elevation pine trees in the Spanish Pyrenees to investigate whether such low‐frequency biases exist and how they alter the long‐term behavior of derived time series. Alignment of the tree ring data by biological age reveals age trends over the first one to four centuries after germination. On average, isotope values change by −0.089‰ δ18O and +0.064‰ δ13C per decade over the first 100 years of tree growth. This trend persists into the forth century after germination for δ18O but diminishes to ∼0‰ over the 100–390 year period for δ13C. We also find level offsets up to 7‰ δ18O and 3‰ δ13C between single trees. Analysis of the shape of age trends reveals negative exponential functions as reasonable choices for detrending of δ18O and (inverted) δ13C time series. The detrended isotope chronologies share low‐frequency variance with traditional ring width and density measurements beyond statistical chance, suggesting that the various parameters reflect some of the same environmental forcing. Our results show that δ18O and δ13C from these Spanish pines need to be detrended to assess long‐term environmental changes. To evaluate the general applicability of this conclusion, production of (1) well‐replicated, (2) nonpooled, and (3) composite chronologies from other species and regions will be required. Increases in measurement speed and technology will make these tests feasible in the coming years.
Influence of volcanic eruptions on the climate of the Asian monsoon region
Authors: Anchukaitis K. J. , Buckley B. M. , Cook E. R. , Cook B. I. , D'Arrigo R. D. , Ammann C. M.
Published: November 2010

Several state‐of‐the‐art general circulation models (GCMs) predict that large volcanic eruptions should result in anomalous dry conditions throughout much of monsoon Asia. Here, we use long and well‐validated proxy reconstructions of Asian droughts and pluvials to detect the influence of volcanic radiative forcing on the hydroclimate of the region since the late Medieval period. Superposed epoch analysis reveals significantly wetter conditions over mainland southeast Asia in the year of an eruption, with drier conditions in central Asia. Our proxy and model comparison suggests that GCMs may not yet capture all of the important ocean‐atmosphere dynamics responsible for the influence of explosive volcanism on the climate of Asia.
Lunar tidal influence on inland river streamflow across the conterminous United States
Authors: Cerveny Randall S. , Svoma Bohumil M. , Vose Russell S.
Published: November 2010

We employ a comprehensive (1900–2009) stream discharge gauge database to analyze the tidal impacts on inland streams. Our analysis reveals a strong lunar phase signal in stream gauge time series across the conterminous United States such that the largest tidal impact on inland rivers is evident at or just after the quarter moon (halfway between full and new moons). As an explanation, we examine precipitation using the Historical Climate Network precipitation dataset. Verifying early studies’ results, we find an equivalent well‐defined lunar phase relationship with precipitation such that the largest tidal impact on precipitation generally occurs just before the quarter moon. Our results imply that inland precipitation is influenced by lunar tides and forces the lagged runoff evident in stream gauges. The lunar‐induced periodicities in the stream gauge network, evident far from ocean‐induced tides, may also influence flooding, as well as water management and power generation.
Pc3 pulsations in the polar cap and at low latitude
Authors: De Lauretis M. , Francia P. , Regi M. , Villante U. , Piancatelli A.
Published: November 2010

We present a statistical analysis of Pc3–4 pulsations during 2005 at two polar cap stations (Terra Nova Bay and Dome C, Antarctica) and, for comparison, at a low‐latitude station (L'Aquila). The analysis technique allows to discriminate the signal component from the background noise in the power spectrum and to determine the frequency of such ULF signal, commonly associated to the upstream wave source. The comparison of data makes evident that the characteristics of the ULF pulsations are different at low and high latitudes, and significant differences emerge also between the two polar cap stations. At Dome C the ULF signals are observed during the whole day, while at Terra Nova Bay and at L'Aquila the signals are mainly observed in the dayside sector. The different cone angle dependence at L'Aquila and Dome C, the steeper slope in the frequency dependence on the interplanetary magnetic field strength at Dome C with respect to L'Aquila and Terra Nova Bay and the time dependence of the coherence between pulsations at the Antarctic stations suggest that at low‐latitude waves are transmitted to the ground from a region close to the subsolar bow shock, while near the geomagnetic pole waves are mainly transmitted through the magnetotail lobes. At Terra Nova Bay, where the local field lines approach the cusp around noon and are stretched into the magnetotail around midnight, the transmission path seems to be time dependent, with daytime and nighttime pulsations penetrating through the subsolar point and via the magnetotail lobes, respectively.
Experimental mechanical and chemical compaction of carbonate sand
Authors: Croizé Delphine , Bjørlykke Knut , Jahren Jens , Renard François
Published: November 2010

Uniaxial compression tests were conducted on bioclastic sand and crushed calcite crystals. Mechanical and chemical processes were investigated to better quantify petrophysical properties of carbonates and their evolution with burial or during fault zone processes. The grain size was in the range 63–500 μm, and the samples were saturated with water in equilibrium with carbonate, glycol, decane, or air. During loading, effective stress was increased to 32 MPa. Mechanical compaction processes (i.e., grain rearrangement, crushing) could be separated from chemical processes (i.e., pressure solution, subcritical crack growth). P and S waves monitored during the tests showed low velocity in samples saturated with reactive fluids. This suggested that chemical reactions at grain contacts reduced the grain framework stiffness. Creep tests were also carried out on bioclastic sand at effective stress of 10, 20, and 30 MPa. No creep was observed in samples saturated with nonreactive fluids. For all the samples saturated with reactive fluids, strain as a function of time was described by a power law of time with a single exponent close to 0.23. Parameters controlling creep rate were, in order of importance, grain size, effective stress, and water saturation. Microstructural observations showed that compaction of bioclastic carbonate sand occurred both mechanically and chemically. Crack propagation probably contributed to mechanical compaction and enhanced chemical compaction during creep. Experimental compaction showed that compaction of carbonates should be modeled as a function of both mechanical and chemical processes, also at relatively shallow depth and low temperature.
Evaluating sampling error in TRMM/PR rainfall products by the bootstrap method: Estimation of the sampling error and its application to a trend analysis
Authors: Iida Yasuhisa , Kubota Takuji , Iguchi Toshio , Oki Riko
Published: November 2010

This study examines a trend in the 7‐year seasonal (i.e., trimonthly) rainfall amounts (September 2001 to August 2008) observed by the TRMM Precipitation Radar (PR). The PR‐observed rainfall amounts averaged in the range of 36°S to 36°N tend to increase slightly over this period. This tendency can be caused not only by natural variations but also by sampling errors (random errors) due to the PR's sparse observations in time. To separate the natural variations from the sampling errors, we developed a method of evaluating the sampling errors by a bootstrap method using the actual data observed by the PR. This method enables an evaluation of regional difference and characteristics of the sampling error in 5° grid boxes. As an application of the simulated sampling errors, we tested the significance of the trends in the averaged rainfall amounts by using Akaike's Information Criterion (AIC) and concluded that the positive trends were significant in all three cases; the trend in rainfall amounts averaged over all observed area (0.283 mm (3 months)−2), that over land (0.518 mm (3 months)−2) and that over the ocean (0.208 mm (3 months)−2). We also tested the significance of the trends in the individual 5° grid boxes during this period and found that regions with the largest trends correspond to those in which the earlier studies have found the precipitation patterns caused by the El Niño‐Southern Oscillation (ENSO).
Facing the credit crunch
Authors: Hunter Philip
Published: November 2010

The global response to the credit crunch has varied from belt tightening to spending sprees. Philip Hunter investigates how various countries react to the financial crisis in terms of supporting scientific research.
Sphingosine kinase and sphingosine 1-phosphate in asthma
Authors: Lai Wen-Qi , Wong W.S. Fred , Leung Bernard P.
Published: November 2010

Sphingolipids are amphiphatic molecules ubiquitously expressed in all eukaryotic cell membranes. Initially characterized as structural components of cell membranes, sphingolipids have emerged as sources of important signalling molecules over the past decade. Sphingolipid metabolites, such as ceramide and S1P (sphingosine 1-phosphate), have been demonstrated to have roles as potent bioactive messengers involved in cell differentiation, proliferation, apoptosis, migration and angiogenesis. The importance of SphK (sphingosine kinase) and S1P in inflammation has been demonstrated extensively. The prevalence of asthma is increasing in many developed nations. Consequently, there is an urgent need for the development of new agents for the treatment of asthma, especially for patients who respond poorly to conventional therapy. Recent studies have demonstrated the important role of SphK and S1P in the development of asthma by regulating pro-inflammatory responses. These novel pathways represent exciting potential therapeutic targets in the treatment of asthma and are described in the present review.