bluuebunny/crossref_metadata_2025 huggingface dataset:
Iron monosulfide (FeS) oxidation by dissolved oxygen: characteristics of the product layer
Authors: Chiriţǎ Paul
Published: February 2009

Samples of FeS were oxidized by oxygen‐bearing acidic solutions at 25 °C and different initial pH values (2.75 ≤ pH ≤ 3.45). The reacted FeS samples were investigated by scanning electron microscopy (SEM), nitrogen adsorption/desorption isotherms measurements, and FT‐Raman spectroscopy. A sulfur rich phase (layer) is inferred to be form on reacting FeS surface based on sequential extraction with acidic chromium(II) chloride solutions. The sulfur‐rich layer (SRL) formed on oxidized FeS samples is traversed by various mesopores with average pore size < 450Å. It is reasonable to assume that the mesopores facilitate the migration of iron and sulfur from FeS structure into solution across SRL. The FT‐Raman spectra of oxidized FeS samples show an intense peak at 162 cm−1, which can be attributed to SRL developed on FeS surface. A model for SRL development on FeS during its oxidation by dissolved oxygen has been proposed from the present results and previous studies. Copyright © 2009 John Wiley & Sons, Ltd.
TFAA chemical derivatization and XPS. Analysis of OH and NHx polymers
Authors: Pippig Falko , Sarghini Sanaa , Holländer Andreas , Paulussen Sabine , Terryn Herman
Published: February 2009

The determination of functional groups on complex polymer surfaces by X‐ray photoelectron spectroscopy (XPS) can be improved considerably by derivatization reactions. Simple polymers containing hydroxyl groups or amino groups were investigated as reference materials for the derivatization with trifluoroacetic anhydride (TFAA).

‐1 Poly(vinyl alcohol) (PVA), poly(hydroxyethyl methacrylate) (PHEMA), poly(vinyl butyral) (PVB), poly(allylamine) (PAAm), and poly(diallyl amine) (PDAAm) were derivatized using TFAA and analyzed with XPS. Polyethylene (PE) was used as an independent external reference for the binding energy (BE). Applying this procedure, the BE scales of all measurements were referenced to the carbon atoms of PE. It was found that the BE of the CF3 component in the C1s region is different when bonded as an acetate or as an amide. The CF3 BE is also influenced by the density of these groups in the polymer molecule. In TFAA‐PVA, where every second main chain carbon atom carries a trifluoroacetate (TFAc) group, the BE is 294.3 eV while in TFAA‐PVB with only isolated groups, the BE is 293.6 eV. The BE of the CF3 component in the trifluoroacetamides (TFAAms) prepared from PAAm and PDAAm was found to be 292.5 and 292.3 eV, respectively. Compared with the analog fluorine free compounds, the BE is shifted toward higher values also for the ester carbon atom, the amide carbon atom, and the carbon atom to which the ester or amide is bonded.

The data suggest that the gas phase reaction of TFAA with a polymer surface is diffusion limited. The actual ester or amide formation is a fast reaction and runs as a wave into the surface. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of Polyphenylene Molecular Wires by Surface‐Confined Polymerization
Authors: Lipton‐Duffin J. A. , Ivasenko O. , Perepichka D. F. , Rosei F.
Published: February 2009

The surface‐mediated synthesis of epitaxially aligned and separated polyphenylene lines on Cu(110) by exploiting the Ullmann dehalogenation reaction is reported. Scanning tunneling microscopy (STM) and X‐ray photoelectron spectroscopy (XPS) show that the C‐I bonds of 1,4‐diiodobenzene and 1,3‐diiodobenzene (C6H4I2) are catalytically cleaved when dosed onto the surface. Subsequent annealing transforms the copper‐bound phenylene intermediates into covalent conjugated structures: linear chains of poly(p‐phenylene) for 1,4‐diiodobenzene and zigzag chains of poly(m‐phenylene) as well as macrocyclic oligomers in the case of 1,3‐diiodobenzene. The chains are strongly bound to the surface (likely through CCu bonds at the chain‐ends) while the macrocycles are very mobile and can only be imaged by STM at low temperature. The detached halogens adsorb on the surface and separate the polymer chains from each other.
Directed Differentiation of Human-Induced Pluripotent Stem Cells Generates Active Motor Neurons
Authors: Karumbayaram Saravanan , Novitch Bennett G. , Patterson Michaela , Umbach Joy A. , Richter Laura , Lindgren Anne , Conway Anne E. , Clark Amander T. , Goldman Steve A. , Plath Kathrin , Wiedau-pazos Martina , Kornblum Harley I. , Lowry William E.
Published: February 2009

The potential for directed differentiation of human-induced pluripotent stem (iPS) cells to functional postmitotic neuronal phenotypes is unknown. Following methods shown to be effective at generating motor neurons from human embryonic stem cells (hESCs), we found that once specified to a neural lineage, human iPS cells could be differentiated to form motor neurons with a similar efficiency as hESCs. Human iPS-derived cells appeared to follow a normal developmental progression associated with motor neuron formation and possessed prototypical electrophysiological properties. This is the first demonstration that human iPS-derived cells are able to generate electrically active motor neurons. These findings demonstrate the feasibility of using iPS-derived motor neuron progenitors and motor neurons in regenerative medicine applications and in vitro modeling of motor neuron diseases.

Disclosure of potential conflicts of interest is found at the end of this article.
Unusual presentation of propionic acidaemia as isolated cardiomyopathy
Authors: Lee T. M. , Addonizio L. J. , Barshop B. A. , Chung W. K.
Published: February 2009

Propionic acidaemia (PA) is an autosomal recessive disease that results from deficiency of propionyl‐CoA carboxylase (PCC). In the majority of reported cases, the phenotype includes metabolic acidosis and/or neurological deficits. We report on a 14‐year‐old Asian‐American male with PA who presented with isolated cardiomyopathy without any documented episodes of metabolic acidosis or evidence of any neurocognitive deficits. On routine metabolic screening, the patient was found to have urine organic acids suggestive of PA. Biochemical and genetic characterization confirmed a PCC deficiency with two novel mutations in PCCB: IVS7 + 2 T > G (c.763 + 2 T > G) and p.R410Q (c.1229 G > A). Residual enzyme activity likely explains our patient's mild phenotype. Splicing mutations tend to result in a milder phenotype as these mutations may still produce small amounts of normal enzyme. In addition, the similar p.R410W mutation has been shown to have partial residual activity. Moreover, this case illustrates that a thorough metabolic evaluation should be performed in both paediatric and adult patients with cardiomyopathy. Such an evaluation has important implications for clinical management and genetic counselling.
The ecology of terrestrial invertebrates on Pacific salmon carcasses
Authors: Hocking Morgan D. , Ring Richard A. , Reimchen Thomas E.
Published: February 2009

In coastal streams throughout the north Pacific region, spawning salmon (Oncorhynchus spp.) subsidize terrestrial communities with their nutrients and carcasses. We document the previously unreported composition and ecology of terrestrial invertebrates using salmon carcasses in forest habitats from two high salmon density watersheds in coastal British Columbia. From experimental placement of 186 carcasses, terrestrial Diptera‐dominated salmon carcass decay (85.5% of carcasses). Overall, we recorded over 60 species from salmon carcasses, including saprophagous Diptera and Coleoptera (15 spp.), dipteran predators (eight spp.) and parasitoids (four spp.), and opportunistic predators, scavengers, and detritivores (24 spp.). Using stable isotopes of nitrogen and carbon, we reconstruct the dietary niches of select species relative to salmon muscle tissue and previously sampled non‐salmon feeding invertebrate species. From comparisons across seasons, sampling locations and larval and adult life stages, we find evidence for a diet of salmon tissue in flies (Calliphora terraenovae and Dryomyza anilis), and beetles (Nicrophorus investigator and Anthobium fimetarium). The parasitic wasps Alysia alticola and Atractodes sp. had the highest levels of enrichment of all species, representing their larval diet of fly larvae that have fed on salmon carcasses 1 year prior to adult wasp sampling. Temporal and spatial isotopic variation in insect indicator species varies by species mobility and the pathway of salmon nutrient uptake. Cataloguing these associations may be useful for developing indices of intact salmon runs, bear foraging, and subsequent nutrient transfer in coastal watersheds.
Using Threshold Autoregressive Models to Study Dyadic Interactions
Authors: Hamaker Ellen L. , Zhang Zhiyong , van der Maas Han L. J.
Published: February 2009

Considering a dyad as a dynamic system whose current state depends on its past state has allowed researchers to investigate whether and how partners influence each other. Some researchers have also focused on how differences between dyads in their interaction patterns are related to other differences between them. A promising approach in this area is the model that was proposed by Gottman and Murray, which is based on nonlinear coupled difference equations. In this paper, it is shown that their model is a special case of the threshold autoregressive (TAR) model. As a consequence, we can make use of existing knowledge about TAR models with respect to parameter estimation, model alternatives and model selection. We propose a new estimation procedure and perform a simulation study to compare it to the estimation procedure developed by Gottman and Murray. In addition, we include an empirical example based on interaction data of three dyads.
Tapered ZnO Whiskers: {hkil}-Specific Mosaic Twinning VLS Growth from a Partially Molten Bottom Source
Authors: Huang Bang-Hao , Shen Pouyan , Chen Shuei-Yuan
Published: February 2009

Zn particulates overlaid with wurtzite (W)-type ZnO condensates having nearly orthogonal "Equation missing" and "Equation missing" facets were found to self-catalyze unusual tapered W-ZnO whiskers upon isothermal atmospheric annealing, i.e., thermal oxidation, at 600 °C. Analytical electron microscopic observations indicated that such whiskers formed tapered slabs having mosaic "Equation missing" and "Equation missing" twinned domains. The tapered whiskers can be rationalized by an alternative vapor–liquid–solid growth, i.e., {hkil}-specific coalescence twinning growth from the ZnO condensates taking advantage of a partially molten bottom source of Zn and the adsorption of atoms at the whisker tips and ledges under the influence of capillarity effect. The tapered whiskers having strong photoluminescence at 391 nm and with a considerable flexibility could have potential applications.
Interaction Between an Anionic and an Amphoteric Surfactant. Part II: Precipitation
Authors: Soontravanich Sukhwan , Walsh Sarah , Scamehorn John F. , Harwell Jeffrey H. , Sabatini David A.
Published: February 2009

Use of amphoteric and anionic surfactants is very common in practical formulations such as shampoos and hand dishwashing products. Precipitation of mixtures of dimethyldodecylamine oxide (DDAO) as an amphoteric surfactant and sodium dodecyl sulfate (SDS) as an anionic surfactant were studied at different pH levels. The DDAO is a pH‐sensitive surfactant and its protonation can be expressed in terms of a pKa similar to an acid dissociation constant. The protonated form of DDAO carries a positive charge and precipitates with the oppositely charged SDS. Therefore, precipitation phase boundaries are pH dependent due to the varying degree of DDAO protonation. By combining the use of regular solution theory and the pseudophase separation model to describe micellar mixing nonidealities with the precipitate solubility product constant and the protonation dissociation constant, a model to predict the precipitation phase boundary is presented here. The model agrees well with experimental phase boundaries at different pH levels.
On the uniqueness of weak solutions for the 3D Navier–Stokes equations
Authors: Zhang Zhifei , Chen Qionglei , Miao Changxing
Published: February 2009

In this paper, we improve some known uniqueness results of weak solutions for the 3D Navier–Stokes equations. The proof uses the Fourier localization technique and the losing derivative estimates.
On the controllability of the fifth-order Korteweg–de Vries equation
Authors: Glass O. , Guerrero S.
Published: February 2009

In this paper, we consider the fifth-order Korteweg–de Vries equation in a bounded interval. We prove that this equation is locally well-posed when endowed with suitable boundary conditions, and establish a result of local controllability to the trajectories.

Dans ce papier, nous considérons l'équation de Korteweg–de Vries du cinquième ordre en domaine borné. Nous montrons que l'équation est localement bien posée lorsque l'on impose certaines données au bord, et établissons un résultat de contrôlabilité locale aux trajectoires.
When demand accelerates demand: Trailing the bandwagon
Authors: van Herpen Erica , Pieters Rik , Zeelenberg Marcel
Published: February 2009

Consumers generally prefer scarce products, which has been related to their exclusiveness. Currently scarce products, however, are not necessarily exclusive, but could be scarce because many other consumers previously bought them. We propose that consumers also prefer scarce products in this situation, which an appeal to uniqueness cannot explain. Three experiments support our predictions and reveal that scarcity effects even occur when consumers only see traces of others' behavior through emptied shelf space. Furthermore, this bandwagon effect disappears when uniqueness is threatened due to others in close spatial distance.
Analgesic efficacy of perioperative use of vedaprofen, tramadol or their combination in cats undergoing ovariohysterectomy
Authors: Brondani Juliana Tabarelli , Luna Loureiro Stelio Pacca , Beier Suzane Lilian , Minto Bruno Wanatabe , Padovani Carlos Roberto
Published: February 2009

The analgesic efficacy of tramadol and/or vedaprofen was evaluated in cats submitted for elective ovariohysterectomy, using a randomised double blind placebo controlled design. Forty adult female cats (3.0±0.32 kg; 1.8±0.7 years) were distributed into four groups. Vedaprofen PO (0.5 mg/kg), tramadol SC (2 mg/kg), both, or placebo was administered 1 h before surgery and every 24 and 8 h, respectively, for 72 h after surgery. Pain score evaluated by interactive visual analogue and composite pain score and hyperalgesia by the von Frey filament test were recorded at 1, 2, 4, 6, 8, 12, 24, 28, 32, 48, 52, 56, 72, 96 h and on the 7th day after surgery. Animals treated with combined vedaprofen and tramadol treatment did not need rescue analgesia, did not develop hyperalgesia, and their serum cortisol concentrations and pain scores were lower than placebo until 24 and 72 h after surgery, respectively. Combined vedaprofen and tramadol treatment provided more effective postoperative analgesia and prevented hyperalgesia than when used on their own. Multimodal technique is a superior method of treating pain after feline ovariohysterectomy. This work also provides evidence for the benefits of analgesia for up to 3 days following ovariohysterectomy.
Feline Uveitis
Authors: Maggs David
Published: February 2009

Practical relevance Feline uveitis can be a subtle, insidious, painful, vision-threatening disease with causes that can sometimes be fatal. It is essential that clinicians remain alert to its various clinical presentations, thoroughly diagnose cases once detected, and treat the primary cause whenever possible.

Clinical challenges In the majority of patients, a cause is not found and aggressive immunomodulating therapy of what may become a chronic or recurrent immune-mediated disease must be instigated. As with immune-mediated diseases elsewhere, this involves local or systemic immunosuppression with slow tapering and frequent monitoring. The aim of this review is to aid diagnosis and therapy of uveitis by likening it to inflammation elsewhere (because it is more similar than it is different) while highlighting differences (because these are helpful).

Global importance Feline uveitis is similar in its presentation throughout the world. Although the list of infectious causes may vary in composition or order of likelihood, idiopathic, immune-mediated and neoplastic causes of feline uveitis are universal.

Patient group Patients of either gender and all ages and breeds are affected by uveitis.

Evidence base Despite the fact that feline uveitis is a serious and common disorder, the peer-reviewed literature regarding this disease is somewhat limited. Approximately half the publications are review articles, case reports or case series. The majority of prospective and retrospective research describes epidemiologic surveys of antibodies, antigens and organism DNA in serum and aqueous humor.
Therapies for Feline Chronic Kidney Disease
Authors: Roudebush Philip , Polzin David J , Ross Sheri J , Towell Todd L , Adams Larry G , Forrester S Dru
Published: February 2009

Practical relevance Successful treatment and prevention of kidney disease in pet animals requires a multidimensional approach to identify and eliminate causes or exacerbating factors, provide professional examination and care on a regular basis, and plan and implement a comprehensive treatment program when necessary.

Evidence base Over the years, many therapeutic and preventive interventions have been developed or advocated for chronic kidney disease (CKD), but evidence of efficacy or effectiveness is often lacking or highly variable. Accordingly, the main objective of this systematic review was to identify and critically appraise the evidence supporting various approaches to managing feline CKD; namely, fluid therapy, calcitrioi therapy, antihypertensive therapy, ACE inhibitor therapy, erythropoietic hormone replacement therapy, potassium supplementation, antioxidant supplementation, alkalinization therapy, dietary phosphorus restriction and intestinal phosphate binders, therapeutic renal foods, assisted feeding, dialysis and renal transplantation.
The coming carbon market and its impact on the American economy
Authors: Peace Janet , Juliani Timothy
Published: February 2009

The likely centerpiece of U.S. legislation to address climate change will be a cap-and-trade program that creates a market for greenhouse gases (GHGs). Whether the onset of a cap-and-trade system and additional complementary policies would provide a benefit or a cost to our economy has been the subject of much modeling and debate. This paper argues that while climate policy does not come without cost, modeling of the Lieberman–Warner Climate Security Act demonstrates that these costs are not substantial and can be mitigated by appropriate policy design. Finally, while a well-designed carbon market will be a large factor in lowering costs and driving innovation, complementary policies will be necessary to induce the technological change required to transition the United States to a low-carbon economy.
The role of the peasant in China’s development plans
Authors: Zaputovich Maria Hrycaiko
Published: February 2009

This paper endeavors to show the importance of history for any study in the social and political sciences. Following theorist and Nobel laureate Douglass C. North, it attempts to show how the past and the present are connected through the continuity of a society’s institutions even when those formal institutions undergo a radical change, that is, revolution. To that end I will be comparing two agricultural societies — Russia and China — beginning with their Imperial periods — to show how their attitudes towards their peasantry have endured through the upheaval of both revolutions and the potential impact on development. The impact of the Russian revolution on China will also be examined.
Why labial-velar stops merge to /gb/
Authors: Cahill Michael C.
Published: February 2009

Most languages with labial-velar stops (i.e. // and //) have both the voiced and voiceless versions, but several dozen languages have only // or only //. Examination of the stop inventories of such languages reveals that in languages which have only // there are always other gaps in the stop inventory, but languages which have only // usually have a full set of other stops, showing that there is a different historical mechanism involved. Also, ‘//-only’ languages are more common than ‘//-only’ languages, despite the cross-linguistic tendency to favour voiceless stops. Comparative studies show that ‘//-only’ languages are often a result of a merger of *and *into //. I propose that this merger is a result of three phonetic characteristics of the phonologically voiceless //, qualities typical of voiced obstruents. Since *is already partly in the ‘voiced camp’, I hypothesise that hearers interpret it as voiced.
Phonetic variability and grammatical knowledge: an articulatory study of Korean place assimilation
Authors: Kochetov Alexei , Pouplier Marianne
Published: February 2009

The study reported here uses articulatory data to investigate Korean place assimilation of coronal stops followed by labial or velar stops, both within words and across words. The results show that this place-assimilation process is highly variable, both within and across speakers, and is also sensitive to factors such as the place of articulation of the following consonant, the presence of a word boundary and, to some extent, speech rate. Gestures affected by the process are generally reduced categorically (deleted), while sporadic gradient reduction of gestures is also observed. We further compare the results for coronals to our previous findings on the assimilation of labials, discussing implications of the results for grammatical models of phonological/phonetic competence. The results suggest that speakers' language-particular knowledge of place assimilation has to be relatively detailed and context-sensitive, and has to encode systematic regularities about its obligatory/variable application as well as categorical/gradient realisation.
Prevocalic faithfulness
Authors: Rubach Jerzy
Published: February 2009

Looking at data from Polish and Ukrainian, this paper addresses the problem of positional faithfulness, in particular onset faithfulness. It is argued that onset faithfulness in its current understanding makes wrong predictions, because it extends the status of privilege to any consonant in the onset. The correct theory is more restrictive and treats as special only the segments that stand before a vowel: prevocalic faithfulness. A further restriction is that the vowel must constitute a syllable nucleus. In effect, then, prevocalic faithfulness refers to onsets, but restricts them to the segment directly before the nucleus.
The calling contour in Hungarian and English
Authors: Varga László
Published: February 2009

This article examines the calling contour (CC) in Hungarian and systematically compares its formal properties with those of its English counterpart. After a critical survey of the literature on the English CC, it carries out a phonological analysis of the Hungarian CC, offering a plausible representation based on that analysis. This contains a H pitch accent (H*) and a downstepped H phrase tone (!H-), corresponding to the first and second terrace of the CC respectively. Other apparent possibilities,viz. that the second H tone is a trailing tone or a boundary tone, are rejected. When the Hungarian CC is utterance-final, it coincides with the final portion of an intonational phrase and needs a boundary tone. It is argued that this boundary tone is neither H% nor L but 0% (H* !H-0%). Hungarian utterances can also contain utterance-internal CCs. These can be analysed as being intermediate phrases, lacking a final boundary tone.
Integration of Trichogramma ostriniae releases and habitat modification for suppression of European corn borer (Ostrinia nubilalis Hübner) in bell peppers
Authors: Russell Kathleen , Bessin Ric
Published: February 2009

A two-year field study was conducted to evaluate the effectiveness of Trichogramma ostriniae Pang et Chen (T.o.) releases in combination with habitat modification, to enhance biological control of European corn borer (ECB), Ostrinia nubilalis Hübner, the key pest of bell peppers in Kentucky. A randomized block design with a split-plot treatment arrangement was used in both years. Buckwheat, Fagopyrum esculetum Moench, was inter-planted as a nectar source for the wasps and as an attractant for ECB natural enemies. Sentinel ECB egg masses were placed in each subplot to monitor establishment and dispersal of T. ostriniae within and between plots. Fruit were harvested at maturity, graded according to USDA standards, inspected for insect damage, and dissected to confirm ECB presence when evidence of entry was suspected, to determine percentage of infested fruits. Percent ECB infested fruit was reduced in plots with wasp releases and in plots with buckwheat inter-planted. The interaction of habitat modification and wasp releases significantly reduced pepper damage as a result of the synergy between tactics. Percentage of T. ostriniae parasitized sentinel eggs was significantly higher in wasp release plots compared to non-release plots. T. ostriniae releases used in conjunction with habitat modification for ECB control in bell peppers appears to be a promising alternative to traditional insecticide-based strategies for small-acreage and organic farms. This study displays an example system utilizing conservation biological control at a landscape level for pest suppression.
GRACE gravity evidence for an impact basin in Wilkes Land, Antarctica
Authors: von Frese Ralph R. B. , Potts Laramie V. , Wells Stuart B. , Leftwich Timothy E. , Kim Hyung Rae , Kim Jeong Woo , Golynsky Alexander V. , Hernandez Orlando , Gaya‐Piqué Luis R.
Published: February 2009

New details on the east Antarctic gravity field from the Gravity Recovery and Climate Experiment (GRACE) mission reveal a prominent positive free‐air gravity anomaly over a roughly 500‐km diameter subglacial basin centered on (70°S, 120°E) in north central Wilkes Land. This regional inverse correlation between topography and gravity is quantitatively consistent with thinned crust from a giant meteorite impact underlain by an isostatically disturbed mantle plug. The inferred impact crater is nearly three times the size of the Chicxulub crater and presumably formed before the Cretaceous formation of the east Antarctic coast that cuts the projected ring faults. It extensively thinned and disrupted the Wilkes Land crust where the Kerguelen hot spot and Gondwana rifting developed but left the adjacent Australian block relatively undisturbed. The micrometeorite and fossil evidence suggests that the impact may have occurred at the beginning of the greatest extinction of life on Earth at ∼260 Ma when the Siberian Traps were effectively antipodal to it. Antipodal volcanism is common to large impact craters of the Moon and Mars and may also account for the antipodal relationships of essentially half of the Earth's large igneous provinces and hot spots. Thus, the impact may have triggered the “Great Dying” at the end of the Permian and contributed to the development of the hot spot that produced the Siberian Traps and now may underlie Iceland. The glacial ice up to a few kilometers thick that has covered the crater for the past 30–40 Ma poses formidable difficulties to sampling the subglacial geology. Thus, the most expedient and viable test of the prospective crater is to survey it for relevant airborne gravity and magnetic anomalies.
Crustal faults exposed in the Pito Deep Rift: Conduits for hydrothermal fluids on the southeast Pacific Rise
Authors: Hayman Nicholas W. , Karson Jeffrey A.
Published: February 2009

The escarpments that bound the Pito Deep Rift (northeastern Easter microplate) expose in situ upper oceanic crust that was accreted ∼3 Ma ago at the superfast spreading (∼142 mm/a, full rate) southeast Pacific Rise (SEPR). Samples and images of these escarpments were taken during transects utilizing the human‐occupied vehicle Alvin and remotely operated vehicle Jason II. The dive areas were mapped with a “deformation intensity scale” revealing that the sheeted dike complex and the base of the lavas contain approximately meter‐wide fault zones surrounded by fractured “damage zones.” Fault zones are spaced several hundred meters apart, in places offset the base of the lavas, separate areas with differently oriented dikes, and are locally crosscut by (younger) dikes. Fault rocks are rich in interstitial amphibole, matrix and vein chlorite, prominent veins of quartz, and accessory grains of sulfides, oxides, and sphene. These phases form the fine‐grained matrix materials for cataclasites and cements for breccias where they completely surround angular to subangular clasts of variably altered and deformed basalt. Bulk rock geochemical compositions of the fault rocks are largely governed by the abundance of quartz veins. When compositions are normalized to compensate for the excess silica, the fault rocks exhibit evidence for additional geochemical changes via hydrothermal alteration, including the loss of mobile elements and gain of some trace metals and magnesium. Microstructures and compositions suggest that the fault rocks developed over multiple increments of deformation and hydrothermal fluid flow in the subaxial environment of the SEPR; faults related to the opening of the Pito Deep Rift can be distinguished by their orientation and fault rock microstructure. Some subaxial deformation increments were likely linked with violent discharge events associated with fluid pressure fluctuations and mineral sealing within the fault zones. Other increments were linked with the influx of relatively fresh seawater. The spacing of the faults is consistent with fault localization occurring every 7000 to 14,000 years, with long‐term slip rates of <3 mm/a. Once spread from the ridge axis, the faults were probably not active, and damage zones likely played a more significant role in axial flank and off‐axis crustal permeability.
Sodium‐ion pickup observed above the magnetopause during MESSENGER's first Mercury flyby: Constraints on neutral exospheric models
Authors: Sarantos Menelaos , Slavin James A. , Benna Mehdi , Boardsen Scott A. , Killen Rosemary M. , Schriver David , Trávníček Pavel
Published: February 2009

Single‐particle tracings of sodium pickup ions launched upstream of Mercury's magnetopause are used to investigate the access of these ions to the magnetosphere and set limits on the distribution of neutral sodium about the planet during the first MESSENGER flyby. The transport of pickup ions is modeled using flow velocity and magnetic fields from a three‐dimensional magnetohydrodynamic simulation. Extensive penetration of pickup ions into the magnetosphere is found in the post‐noon and dusk local time sectors due to the northward interplanetary magnetic field at the time of MESSENGER's first flyby. It is concluded that: (1) pickup of magnetosheath photoions may be an important source of hot planetary ions within the magnetosphere; and (2) the sodium ions in the magnetosheath observed by MESSENGER must originate from an extended neutral exosphere due to ion sputtering and/or to a partially escaping distribution generated by photon‐stimulated desorption with yields modified by regolith trapping.
Complementary observational constraints on climate sensitivity
Authors: Urban Nathan M. , Keller Klaus
Published: February 2009

A persistent feature of empirical climate sensitivity estimates is their heavy tailed probability distribution indicating a sizeable probability of high sensitivities. Previous studies make general claims that this upper heavy tail is an unavoidable feature of (i) the Earth system, or of (ii) limitations in our observational capabilities. Here we show that reducing the uncertainty about (i) oceanic heat uptake and (ii) aerosol climate forcing can—in principle—cut off this heavy upper tail of climate sensitivity estimates. Observations of oceanic heat uptake result in a negatively correlated joint likelihood function of climate sensitivity and ocean vertical diffusivity. This correlation is opposite to the positive correlation resulting from observations of surface air temperatures. As a result, the two observational constraints can rule out complementary regions in the climate sensitivity‐vertical diffusivity space, and cut off the heavy upper tail of the marginal climate sensitivity estimate.
Gravity‐driven deformation of Tenerife measured by InSAR time series analysis
Authors: Fernández J. , Tizzani P. , Manzo M. , Borgia A. , González P. J. , Martí J. , Pepe A. , Camacho A. G. , Casu F. , Berardino P. , Prieto J. F. , Lanari R.
Published: February 2009

We study the state of deformation of Tenerife (Canary Islands) using Differential Synthetic Aperture Radar Interferometry (DInSAR). We apply the Small BAseline Subset (SBAS) DInSAR algorithm to radar images acquired from 1992 to 2005 by the ERS sensors to determine the deformation rate distribution and the time series for the coherent pixels identified in the island. Our analysis reveals that the summit area of the volcanic edifice is characterized by a rather continuous subsidence extending well beyond Las Cañadas caldera rim and corresponding to the dense core of the island. These results, coupled with GPS ones, structural and geological information and deformation modeling, suggest an interpretation based on the gravitational sinking of the dense core of the island into a weak lithosphere and that the volcanic edifice is in a state of compression. We also detect more localized deformation patterns correlated with water table changes and variations in the deformation time series associated with the seismic crisis in 2004.
A statistical study of the open magnetic flux content of the magnetosphere at the time of substorm onset
Authors: Boakes P. D. , Milan S. E. , Abel G. A. , Freeman M. P. , Chisham G. , Hubert B.
Published: February 2009

In this paper we determine the probability of substorm onset as a function of open magnetic flux in the magnetosphere by comparing the occurrence distribution of open flux observed at all times with that observed at the time of substorm onset. The open magnetic flux is measured in 12735 auroral images of the ionospheric polar cap from the IMAGE WIC detector. The probability of substorm onset is found to be negligible for fluxes below ∼0.3 GWb, increases almost linearly until ∼0.9 GWb, and is undefined above this. We also demonstrate that those substorms which show a clear particle injection signature at geosynchronous orbit, as measured by the LANL spacecraft, occur, on average, with higher values of open flux than those showing no activity. We discuss these results in the context of various hypotheses for substorm onset.
Estimates of ground‐level aerosol mass concentrations using a chemical transport model with Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol observations over East Asia
Authors: Choi Yong‐Sang , Park Rokjin J. , Ho Chang‐Hoi
Published: February 2009

We estimate ground‐level mass concentrations of PM2.5 and PM10 (particulate matter smaller than 2.5 and 10 μm in diameter, respectively) for 2001 using a global chemical transport model with Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) retrievals. Our method improves on previous techniques by using a new satellite product (fine‐mode fraction (FMF)) and is applied to East Asia, where such an approach has not previously been attempted. We evaluate the method by comparing the PM estimates with the observations from Air Quality System sites and Acid Deposition Monitoring Network sites across East Asia. The spatial patterns of the annual and seasonal means of the estimated PM10 concentrations are in better agreement with the observations than the results of the model alone. The PM2.5 estimates based on both MODIS AOD and FMF data show considerable improvement relative to those using AOD data alone or simply the model and are in better agreement with the observations at three available sites in Korea and Japan. The greatest improvement is found in the cases where the model significantly underestimates the data. Our best estimates of the annual mean PM2.5 and PM10 concentrations over East Asia are 14.7 and 71.2 μg m−3, respectively. However, the uncertainties in our PM2.5 and PM10 estimates are up to 2.5 and 20 μg m−3, respectively.
Catchments as simple dynamical systems: Catchment characterization, rainfall‐runoff modeling, and doing hydrology backward
Authors: Kirchner James W.
Published: February 2009

Water fluxes in catchments are controlled by physical processes and material properties that are complex, heterogeneous, and poorly characterized by direct measurement. As a result, parsimonious theories of catchment hydrology remain elusive. Here I describe how one class of catchments (those in which discharge is determined by the volume of water in storage) can be characterized as simple first‐order nonlinear dynamical systems, and I show that the form of their governing equations can be inferred directly from measurements of streamflow fluctuations. I illustrate this approach using data from the headwaters of the Severn and Wye rivers at Plynlimon in mid‐Wales. This approach leads to quantitative estimates of catchment dynamic storage, recession time scales, and sensitivity to antecedent moisture, suggesting that it is useful for catchment characterization. It also yields a first‐order nonlinear differential equation that can be used to directly simulate the streamflow hydrograph from precipitation and evapotranspiration time series. This single‐equation rainfall‐runoff model predicts streamflow at Plynlimon as accurately as other models that are much more highly parameterized. It can also be analytically inverted; thus, it can be used to “do hydrology backward,” that is, to infer time series of whole‐catchment precipitation directly from fluctuations in streamflow. At Plynlimon, precipitation rates inferred from streamflow fluctuations agree with rain gauge measurements as closely as two rain gauges in each catchment agree with each other. These inferred precipitation rates are not calibrated to precipitation measurements in any way, making them a strong test of the underlying theory. The same approach can be used to estimate whole‐catchment evapotranspiration rates during rainless periods. At Plynlimon, evapotranspiration rates inferred from streamflow fluctuations exhibit seasonal and diurnal cycles that agree semiquantitatively with Penman‐Monteith estimates. Thus, streamflow hydrographs may be useful for reconstructing precipitation and evapotranspiration records where direct measurements are unavailable, unreliable, or unrepresentative at the scale of the landscape.
Ins(1,4,5)P3 receptor type 1 associates with AKAP9 (AKAP450 variant) and protein kinase A type IIβ in the Golgi apparatus in cerebellar granule cells
Authors: Collado‐Hilly Mauricette , Coquil Jean‐François
Published: February 2009

Background information. Interconnections between the Ca2+ and cAMP signalling pathways can determine the specificity and diversity of the cellular effects mediated by these second messengers. Most cAMP effects are mediated by PKA (protein kinase A), which is anchored close to its membranous substrates by AKAPs (A kinase‐anchoring proteins). In many cell types, the activation of InsP3R (inositol 1,4,5‐trisphosphate receptor), an endoplasmic reticulum Ca2+ channel, is a key event of Ca2+ signalling. The phosphorylation of InsP3R1 by PKA stimulates Ca2+ mobilization. This control is thought to be tight, involving the association of PKA with InsP3R1. The InsP3R1 isoform predominates in central nervous tissue and its concentration is highest in the cerebellar microsomes. We investigated the complex formed by InsP3R1 and PKA in this fraction, vith a view to identifying its components and determining its distribution in the cerebellar cortex.

Results. Immunoprecipitation experiments showed that InsP3R1 associated with PKA type IIβ and AKAP450, the longer variant of AKAP9, in sheep cerebellar microsomes. The co‐purification of AKAP450 with InsP3R1 on heparin‐agarose provided further evidence of the association of these proteins. Immunohistofluorescence experiments on slices of cerebellar cortex showed that AKAP450 was colocalized with InsP3R1 and RIIβ (regulatory subunit of PKA IIβ) in granule cells, but not in Purkinje cells. AKAP450 was localized in the Golgi apparatus of these two cell types whereas InsP3R1 was detected in this organelle only in granule cells.

Conclusions. Taken together these results suggest that InsP3R1 forms a complex with AKAP450 and PKAIIβ, localized in the Golgi apparatus of cerebellar granule cells. In contrast, the association of InsP3R1 with PKA in Purkinje cells would require a different macromolecular complex.
Progesterone induces nano‐scale molecular modifications on endometrial epithelial cell surfaces
Authors: Francis Lewis W. , Lewis Paul D. , Gonzalez Deyarina , Ryder Timothy A. , Webb Gordon , Joels Lisa A. , White John O. , Wright Chris J. , Conlan R. Steve
Published: February 2009

Background information. The endometrial epithelial cell membrane is a key interface in female reproductive biology. Steroid hormones play a predominant role in cyclic changes which occur at this interface during the female menstrual cycle. Specific changes in the morphology of the endometrial epithelial cell surface become apparent with the epithelial transition that drives the switch from a non‐receptive to receptive surface due to the action of progesterone on an oestrogen primed tissue. AFM (atomic force microscopy) allows the high‐resolution characterization of the endometrial epithelial cell surface. Its contact probe mechanism enables a unique imaging method that requires little sample preparation, yielding topographical and morphological characterization. By stiffening the cell membrane, low concentrations of fixatives allow the surface detail of the cell to be resolved while preserving fine ultra‐structural details for analysis.

Results. In the present study we use high resolution AFM analysis of endometrial epithelial cells to monitor the effect of progesterone on the nanoscale structure of the endometrial cell surface. High‐resolution imaging reveals similar topographical nanoscale changes in both the Hec‐1‐A and Ishikawa model cell lines. Hec‐1‐B cells, used in the present study as a progesterone receptor negative control, however, exhibit a flattened cell surface morphology following progesterone treatment. Changes in average cell height and surface convolution correlate with increased surface roughness measurements, demonstrating alterations in molecular structure on the cell surface due to hormonal stimulation.

Conclusions. Progesterone treatment induces changes to the cell surface as a result of nanoscale molecular modifications in response to external hormonal treatments. AFM provides the basis for the identification, visualization and quantification of these cell surface nanoscale changes. Together these findings demonstrate the utility of AFM for use in reproductive science and cancer biology where it could be applied in both in vitro analysis of protein structure—function relationships and clinical diagnosis.
Dual roles of Lys57 at the dimer interface of human mitochondrial NAD(P)+-dependent malic enzyme
Authors: Hsieh Ju-Yi , Liu Jyung-Hurng , Fang Yi-Wen , Hung Hui-Chih
Published: February 2009

Human m-NAD(P)-ME [mitochondrial NAD(P)+-dependent ME (malic enzyme)] is a homotetramer, which is allosterically activated by the binding of fumarate. The fumarate-binding site is located at the dimer interface of the NAD(P)-ME. In the present study, we decipher the functional role of the residue Lys57, which resides at the fumarate-binding site and dimer interface, and thus may be involved in the allosteric regulation and subunit–subunit interaction of the enzyme. In the present study, Lys57 is replaced with alanine, cysteine, serine and arginine residues. Site-directed mutagenesis and kinetic analysis strongly suggest that Lys57 is important for the fumarate-induced activation and quaternary structural organization of the enzyme. Lys57 mutant enzymes demonstrate a reduction of Km and an elevation of kcat following induction by fumarate binding, and also display a much higher maximal activation threshold than WT (wild-type), indicating that these Lys57 mutant enzymes have lower affinity for the effector fumarate. Furthermore, mutation of Lys57 in m-NAD(P)-ME causes the enzyme to become less active and lose co-operativity. It also increased K0.5,malate and decreased kcat values, indicating that the catalytic power of these mutant enzymes was significantly impaired following mutation of Lys57. Analytical ultracentrifugation analysis demonstrates that the K57A, K57S and K57C mutant enzymes dissociate predominantly into dimers, with some monomers present, whereas the K57R mutant forms a mixture of dimers and tetramers, with a small amount of the enzyme in monomeric form. The dimeric form of these Lys57 mutants, however, cannot be reconstituted into tetramers with the addition of fumarate. Modelling structures of the Lys57 mutant enzymes show that the hydrogen bond network in the dimer interface where Lys57 resides may be reduced compared with WT. Although the fumarate-induced activation effects are partially maintained in these Lys57 mutant enzymes, the mutant enzymes cannot be reconstituted into tetramers through fumarate binding and cannot recover their full enzymatic activity. In the present study, we demonstrate that the Lys57 residue plays dual functional roles in the structural integrity of the allosteric site and in the subunit–subunit interaction at the dimer interface of human m-NAD(P)-ME.
Biochemical evidence of the interactions of membrane type-1 matrix metalloproteinase (MT1-MMP) with adenine nucleotide translocator (ANT): potential implications linking proteolysis with energy metabolism in cancer cells
Authors: Radichev Ilian A. , Remacle Albert G. , Sounni Nor Eddine , Shiryaev Sergey A. , Rozanov Dmitri V. , Zhu Wenhong , Golubkova Natalya V. , Postnova Tatiana I. , Golubkov Vladislav S. , Strongin Alex Y.
Published: February 2009

Invasion-promoting MT1-MMP (membrane type-1 matrix metalloproteinase) is a key element in cell migration processes. To identify the proteins that interact and therefore co-precipitate with this proteinase from cancer cells, we used the proteolytically active WT (wild-type), the catalytically inert E240A and the C-end truncated (tailless; ΔCT) MT1-MMP–FLAG constructs as baits. The identity of the pulled-down proteins was determined by LC-MS/MS (liquid chromatography tandem MS) and then confirmed by Western blotting using specific antibodies. We determined that, in breast carcinoma MCF cells (MCF-7 cells), ANT (adenine nucleotide translocator) efficiently interacted with the WT, E240A and ΔCT constructs. The WT and E240A constructs also interacted with α-tubulin, an essential component of clathrin-mediated endocytosis. In turn, tubulin did not co-precipitate with the ΔCT construct because of the inefficient endocytosis of the latter, thus suggesting a high level of selectivity of our test system. To corroborate these results, we then successfully used the ANT2–FLAG construct as a bait to pull-down MT1-MMP, which was naturally produced by fibrosarcoma HT1080 cells. We determined that the presence of the functionally inert catalytic domain alone was sufficient to cause the proteinase to interact with ANT2, thus indicating that there is a non-proteolytic mode of these interactions. Overall, it is tempting to hypothesize that by interacting with pro-invasive MT1-MMP, ANT plays a yet to be identified role in a coupling mechanism between energy metabolism and pericellular proteolysis in migrating cancer cells.