bluuebunny/crossref_metadata_2025 huggingface dataset:
Post-operative respiratory distress following primary cleft palate repair
Authors: Smith D , Abdullah S E F H J , Moores A , Wynne D M
Published: November 2012

Introduction:

Infants are obligate nasal breathers. Cleft palate closure may result in upper airway compromise. We describe children undergoing corrective palatal surgery who required unplanned airway support.

Setting:

Tertiary referral unit.

Method:

Retrospective study (2007–2009) of 157 cleft palate procedures (70 primary procedures) in 43 patients. Exclusion criteria comprised combined cleft lip and palate, secondary palate procedure, and pre-existing airway support.

Results:

The children's mean age was 7.5 months and their mean weight 7.72 kg. Eight children were syndromic, and eight underwent pre-operative sleep studies (five positive, three negative). Post-operatively, five developed respiratory distress and four required oxygen, both events significantly associated with pre-operative obstructive sleep apnoea (p = 0.001 and 0.015, respectively). Four desaturated within 24 hours. Five required a nasopharyngeal airway. Hospital stay (mean, 4 days) was significantly associated with obstructive sleep apnoea (p = 0.002) and nasopharyngeal airway insertion (p = 0.017).

Discussion:

Pre-operative obstructive sleep apnoea correlated significantly with post-operative respiratory distress, supplementary oxygen requirement, nasopharyngeal airway insertion and hospital stay. We recommend pre-operative sleep investigations for all children undergoing cleft palate repair, to enable appropriate timing of the procedure.
Effect of the inter-grain attractive potential on lattice dynamics in complex plasmas
Authors: VERMA M. P. , MISHRA S. K. , SODHA M. S.
Published: November 2012

The dispersion relation for lattice waves in a linear chain of charged particles in a complex plasma has been derived on the basis of a screened inter-grain repulsive potential and an attractive shadow potential 1/r. It is seen that the inclusion of the attractive potential makes a significant difference in the results; the present results are in good agreement with the experiment. The dispersion relations, corresponding to square and hexagonal planar lattices, with vibrations confined to the plane have also been derived.
Ion-acoustic shock waves in a degenerate dense plasma
Authors: ZOBAER M. S. , ROY N. , MAMUN A. A.
Published: November 2012

A theoretical investigation on the nonlinear propagation of ion-acoustic waves in a degenerate dense plasma has been made by employing the reductive perturbation method. The Burger's equation has been derived, and numerically analyzed. The basic features of electrostatic shock structures have been examined. It has been shown that the plasma system under consideration supports the propagation of electrostatic shock structures. The implications of our results (obtained from this investigation) in compact astrophysical objects have been briefly discussed.
Dust acoustic instability with non-extensive distribution
Authors: LIU SAN QIU , QIU HUI BIN
Published: November 2012

The instability of dust acoustic waves driven by electrons and ions with different drift velocities in dusty non-extensive plasma is investigated based on the kinetic theory. The non-extensivity parameters of non-extensive distribution for three plasma components are different from each other. The instability growth rate is shown to be dependent on the non-extensivity parameters as well as on the ion--electron number density ratio. In the extensive limit (q=1), the result in Maxwellian distribution plasma is recovered. The instability growth rate is found to decrease as the population of suprathermal electrons and dust grains increases, but it enhances when the number of suprathermal ions increases and electron density decreases.
Leucothoe cathalaa sp. nov. (Crustacea: Amphipoda: Leucothoidae), a new bathyal benthic species from the Le Danois Bank (‘El Cachucho’ Spanish MPA), southern Bay of Biscay
Authors: Frutos Inmaculada , Sorbe Jean Claude
Published: November 2012

A new bathyal leucothoid amphipod, Leucothoe cathalaa sp. nov., is described and illustrated based on specimens collected at the Le Danois Bank (‘El Cachucho’ Marine Protected Area), southern Bay of Biscay. This species can be distinguished from the other species of the genus Leucothoe by the hardly visible eyes (translucent ocelli, in preserved specimens); antenna 1 with minute accessory flagellum; coxae 1–3 with 2 serrations on posterodistal margin; epimeron 3 posterodistal corner produced, bifid, with one seta between blunt lobes and telson apex pointed without accessory teeth. In live specimens, the eyes are easily visible, each represented as a rounded whitish-pigmented spot. The new species has been found living on fine sandy soft-bottoms between 486 and 574 m depth at the top of the bank. An identification key to the deep Atlantic European species of Leucothoe is provided, as well as ecological and biological comments.
Feeding habits of the apron ray,Discopyge tschudii(Elasmobranchii: Narcinidae), from off Uruguay and northern Argentina
Authors: Spath M. Cecilia , Barbini Santiago A. , Figueroa Daniel E.
Published: November 2012

The feeding habits of the apron ray,Discopyge tschudii, were investigated, off Uruguay and northern Argentina, and we tested the hypothesis that the diet changes with increasing body size, between sexes and seasons using a multiple-hypothesis modelling approach.Discopyge tschudiipreys mainly on polychaetes (88.77% index of relative importance (IRI)) followed by siphons of the clamAmiantis purpurata(8.13% IRI) and amphipods (3.08% IRI). Ontogenetic, sexual and seasonal changes were found. Larger individuals ofD. tschudiiconsumed buried polychaetes more often. The consumption of errant polychaetes was higher in males and in the cold season. Also, amphipods were preyed on more heavily by females and the number of siphons ofA. purpurataconsumed was higher in the cold season.
Spatial structuring of submerged aquatic vegetation in an estuarine habitat of the Gulf of Mexico
Authors: Burgos-León Aretha Moriana , Valdés David , Vega Ma. Eugenia , Defeo Omar
Published: November 2012

Seasonal changes in spatial structure of biomass of submerged aquatic vegetation (SAV) and environmental variables were evaluated in Celestun Lagoon, an estuarine habitat in Mexico. Geostatistical techniques were used to evaluate spatial autocorrelation and to predict the spatial distribution by kriging. The relative contribution of 11 environmental variables in explaining the spatial structure of biomass of SAV was evaluated by canonical correspondence analysis. Spatial partitioning between species of SAV was evident: the seagrasses Halodule wrightii and Ruppia maritima dominated the seaward and central zones of the lagoon, respectively, whereas the green alga Chara fibrosa was constrained to the inner zone. The spatial structure and seasonal variability of SAV biomass were best explained by organic carbon in the sediments, salinity and total suspended solids in the water column. Analysis at different spatial scales allowed identifying the importance of spatial structure in biotic and abiotic variables of this estuarine habitat.
Lobster (Homarus americanus), a new host for marine horsehair worms (Nectonema agile, Nematomorpha)
Authors: Schmidt-Rhaesa Andreas , Pohle Gerhard , Gaudette Julien , Burdett-Coutts Victoria
Published: November 2012

Nectonema species are parasites of decapod crustaceans and the only known representatives of the otherwise freshwater/terrestrial taxon Nematomorpha. We report the American lobster, Homarus americanus, as a new host for Nectonema agile, a first record among astacidean decapods. A female, about 590 mm long, was found in the body cavity of one female lobster specimen. We assume lobster to be a very rare host for Nectonema.
The reproductive cycle of a deep-sea eel, Nettastoma melanurum (Nettastomatidae: Anguilliformes) from the south-eastern Sardinian Sea (central-western Mediterranean)
Authors: Porcu Cristina , Follesa Maria Cristina , Gastoni Alice , Mulas Antonello , Pedoni Claudia , Cau Angelo
Published: November 2012

The reproductive cycle of the deep-sea eel Nettastoma melanurum was described based on 397 specimens (171 males and 226 females). Experimental trawl surveys between depths of 772 and 1598 m and commercial hauls (580–600 m) on compact mud bottoms off the south-eastern Sardinian waters (central-western Mediterranean) were carried out. The Sardinian catches did not indicate any particular trend of size-range in relation to depth in both sexes and seem to be sexually dimorphic with females growing almost 9 cm longer than males at maximum lengths. It was a dioeceous and an oviparous deep-sea species. For females and males, six stages of oocyte development, characterizing the different stages of maturity, were identified. Histological examination demonstrated that ovaries of N. melanurum showed a ‘group-synchronous’ pattern, highlighting a type of monocyclic ovary. The species showed a size at first maturity of 53.5 cm and 50.5 cm total length in females and males respectively. The reproductive period appeared to be unique and well defined in both sexes. Their monthly changes of gonadosomatic index and maturation phases of ovaries and testis showed that the species was in a resting period from March to July. Vitellogenesis and spawning began in September and ended in January. Nettastoma melanurum seemed to be a fecund species (8132–18755 eggs).
Running against time: conservation of the remaining hawksbill turtle (Eretmochelys imbricata) nesting population in the Dominican Republic
Authors: Revuelta Ohiana , León Yolanda M. , Aznar Francisco J. , Raga Juan A. , Tomás Jesús
Published: November 2012

Saona Island hosts the last hawksbill turtle (Eretmochelys imbricata) nesting population in the Dominican Republic, which has experienced a severe decline in the last decades, mostly due to illegal egg take. Here we present the results of an artificial incubation programme started in 2007 to protect the clutches from human predation. A preliminary survey in 2006 showed that about 60% of clutches laid were taken by humans. Over the study period (2007–2010) we recorded 400 clutches, of which 38.2% were predated by humans, 40.7% were artificially incubated and 21% were incubated in situ. Overall, the artificial incubation programme allowed the release of 12,340 hatchlings. No differences were found in hatching and emergence success between clutches incubated in situ and clutches artificially incubated. However, incubation temperatures and incubation durations recorded suggest a male-biased hatchling sex-ratio in artificially incubated clutches. Although artificial incubation may mitigate the effect of egg take, our results indicate that other measures, such as clutch relocation to protected sections of the beach should be taken. Beach patrolling and education are currently implemented so that artificial incubation will be eventually phased out in favour of in situ incubation.
Epibiosis and hyperepibiosis onPagurus bernhardus(Crustacea: Decapoda) from the west Coast of Scotland
Authors: Fernandez-Leborans Gregorio , Dávila Patricia , Cerezo Eva , Contreras Cristina
Published: November 2012

The presence of a diverse range of epibionts was found onPagurus bernhardusfrom the west coast of Scotland. The invertebrate species found on the shell inhabited by the crab were the hydrozoansHydractinia echinataandDycorine conferta, the cirripedsBalanus balanusandBalanus crenatus, the polychaetesHydroides norvegica,Pomatoceros triqueterandCirceis armoricana, and the molluscsHiatella arcticaandAnomia ephippium. On the crab were observed the polychaeteCirceis armoricanaand the amphipodPodoceropsis nitida. In addition, on the gastropod shells occupied byP. bernhardus, ciliate protozoan species were found attached to the hydrozoanDycorine conferta, this being hyperepibiosis. These ciliates were 6 suctorian (Conchacineta constricta,Corynophrya anisostyla,Actinocyathula homari,Actinocyathula crenata,Acineta sulcataandAcineta corophii), and one peritrich species (Zoothamniumsp.). This is the first time that this hyperepibiosis was observed. In contrast to the epibiont communities observed in previous surveys in the same sampling area, basibiont specimens withoutD. confertadid not show ciliate epibionts. The ciliate epibionts also were not present on the surface of the shell and crab in specimens withD. conferta; they only appeared in hyperepibiosis on the surface of the hydrozoan. The spatial distribution and abundance of the invertebrate epibiont species were analysed, as well as the morphology, taxonomy and distribution of the ciliate hyperepibionts.
Trophic spectrum of the sailfishIstiophorus platypteruscaught off Acapulco in the southern Mexican Pacific
Authors: Hernández-Aguilar Sandra Berenice , Abitia-Cárdenas Leonardo Andrés , Moreno-Sánchez Xchel Gabriel , Arellano-Martínez Marcial , González-Rodríguez Eduardo
Published: November 2012

The sailfishIstiophorus platypterusis one of the most common billfish species in the Mexican Pacific. Information about its feeding habits in the coastal region of Acapulco, Guerrero is extremely limited. In the present study we quantified the diet of sailfish, based on captures made from March 2008 to December 2009 by the sport fishing fleet of Acapulco. We analysed a total of 561 stomachs, of which 254 contained food (45%). The size interval of examined specimens was between 101 and 212 cm postorbital length and between 15 and 47 kg total weight. In general, teleosts were the most important prey, followed by cephalopods. According to index of relative importance, the most important species in the diet were the fishAuxis thazard(63.04%) andFistularia commersonii(6.62%), followed by the cephalopodOctopusspp. (4.58%). There were no significant differences in the diet by sex (males and females), sexual maturity (immature and mature), or by season (warm and cold seasons). In all cases the most important prey species wasA. thazard. We conclude that the sailfishI. platypterusoff Acapulco behaves as a specialist predator because, despite the consumption of a high number of prey items, it feeds preferentially on a reduced number of prey species that form schools, and are available and abundant in the ocean.
Evaluation of matrix-assisted laser desorption/ionization time of flight mass spectrometry for the identification of ceratopogonid and culicid larvae
Authors: STEINMANN I. C. , PFLÜGER V. , SCHAFFNER F. , MATHIS A. , KAUFMANN C.
Published: November 2012

Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) was evaluated for the rapid identification of ceratopogonid larvae. Optimal sample preparation as evaluated with laboratory-reared biting midgesCulicoides nubeculosuswas the homogenization of gut-less larvae in 10% formic acid, and analysis of 0·2 mg/ml crude protein homogenate mixed with SA matrix at a ratio of 1:1·5. Using 5 larvae each of 4 ceratopogonid species (C. nubeculosus,C. obsoletus,C. decor, andDasyheleasp.) and of 2 culicid species (Aedes aegypti,Ae. japonicus), biomarker mass sets between 27 and 33 masses were determined. In a validation study, 67 larvae belonging to the target species were correctly identified by automated database-based identification (91%) or manual full comparison (9%). Four specimens of non-target species did not yield identification. As anticipated for holometabolous insects, the biomarker mass sets of adults cannot be used for the identification of larvae, and vice versa, because they share only very few similar masses as shown forC. nubeculosus,C. obsoletus, andAe. japonicus. Thus, protein profiling by MALDI-TOF as a quick, inexpensive and accurate alternative tool is applicable to identify insect larvae of vector species collected in the field.
Thought disorder in the meta-structure of psychopathology
Authors: Keyes K. M. , Eaton N. R. , Krueger R. F. , Skodol A. E. , Wall M. M. , Grant B. , Siever L. J. , Hasin D. S.
Published: November 2012

Background

Dimensional models of co-morbidity have the potential to improve the conceptualization of mental disorders in research and clinical work, yet little is known about how relatively uncommon disorders may fit with more common disorders. The present study estimated the meta-structure of psychopathology in the US general population focusing on the placement of five under-studied disorders sharing features of thought disorder: paranoid, schizoid, avoidant and schizotypal personality disorders, and manic episodes as well as bipolar disorder.

Method

Data were drawn from the National Epidemiologic Survey on Alcohol and Related Conditions, a face-to-face interview of 34 653 non-institutionalized adults in the US general population. The meta-structure of 16 DSM-IV Axis I and Axis II psychiatric disorders, as assessed by the Alcohol Use Disorder and Associated Disabilities Interview Schedule DSM-IV version (AUDADIS-IV), was examined using exploratory and confirmatory factor analysis.

Results

We document an empirically derived thought disorder factor that is a subdomain of the internalizing dimension, characterized by schizoid, paranoid, schizotypal and avoidant personality disorders as well as manic episodes. Manic episodes exhibit notable associations with both the distress subdomain of the internalizing dimension as well as the thought disorder subdomain. The structure was replicated for bipolar disorder (I or II) in place of manic episodes.

Conclusions

As our understanding of psychopathological meta-structure expands, incorporation of disorders characterized by detachment and psychoticism grows increasingly important. Disorders characterized by detachment and psychoticism may be well conceptualized, organized and measured as a subdimension of the internalizing spectrum of disorders. Manic episodes and bipolar disorder exhibit substantial co-morbidity across both distress and thought disorder domains of the internalizing dimension. Clinically, these results underscore the potential utility of conceptualizing patient treatment needs using an approach targeting psychopathological systems underlying meta-structural classification rubrics.
The neural basis of flashback formation: the impact of viewing trauma
Authors: Bourne C. , Mackay C. E. , Holmes E. A.
Published: November 2012

Background

Psychological traumatic events, such as war or road traffic accidents, are widespread. A small but significant proportion of survivors develop post-traumatic stress disorder (PTSD). Distressing, sensory-based involuntary memories of trauma (henceforth ‘flashbacks’) are the hallmark symptom of PTSD. Understanding the development of flashbacks may aid their prevention. This work is the first to combine the trauma film paradigm (as an experimental analogue for flashback development) with neuroimaging to investigate the neural basis of flashback aetiology. We investigated the hypothesis that involuntary recall of trauma (flashback) is determined during the original event encoding.

Method

A total of 22 healthy volunteers viewed a traumatic film whilst undergoing functional magnetic resonance imaging (fMRI). They kept a 1-week diary to record flashbacks to specific film scenes. Using a novel prospective fMRI design, we compared brain activation for those film scenes that subsequently induced flashbacks with both non-traumatic control scenes and scenes with traumatic content that did not elicit flashbacks (‘potentials’).

Results

Encoding of scenes that later caused flashbacks was associated with widespread increases in activation, including in the amygdala, striatum, rostral anterior cingulate cortex, thalamus and ventral occipital cortex. The left inferior frontal gyrus and bilateral middle temporal gyrus also exhibited increased activation but only relative to ‘potentials’. Thus, these latter regions appeared to distinguish between traumatic content that subsequently flashed back and comparable content that did not.

Conclusions

Results provide the first prospective evidence that the brain behaves differently whilst experiencing emotional events that will subsequently become involuntary memories – flashbacks. Understanding the neural basis of analogue flashback memory formation may aid the development of treatment interventions for this PTSD feature.
MARTIAL MINOANS? WAR AS SOCIAL PROCESS, PRACTICE AND EVENT IN BRONZE AGE CRETE
Authors: Molloy Barry P.C.
Published: November 2012

Together with politics, economics and religion, war is one of the fundamental factors that can shape a society and group identities. In the prehistoric world, the sources for the study of war are disparate and their interpretation can be inconsistent and problematic. In the case of Crete in the Bronze Age, a systematic analysis of the evidence will be undertaken for the first time in this paper, and this opportunity is used to critically evaluate the most effective ways of employing the widely agreed sets of physical correlates for ancient war in the archaeological record. A further objective in exploring the diachronic roles of war in these societies is to move the discussion from a niche field to a more integrated, and systematic, social analysis. The existence and character of a warrior identity is examined, and it is proposed that it often constituted a conspicuous element of male identity. The varying scales and time spans through which war can influence a society are discussed, and a broad framework for understanding war in social process, practices and events is proposed.
Epidemiology of infectious encephalitis, differences between a prospective study and hospital discharge data
Authors: BERNARD S. , MAILLES A. , STAHL J. P.
Published: November 2012

The French epidemiology of infectious encephalitis has been described in a 2007 prospective study. We compared these results with available data (demographic features, causative agents, case-fatality ratio) obtained through the French national hospital discharge 2007 database (PMSI), in order to evaluate it as a surveillance tool for encephalitis. Causative agents were identified in 52% of cases in the study, and 38% in PMSI (P < 0·001). The incidence of encephalitis in France in 2007 was estimated as 2·6 cases/100 000 inhabitants. HSV and VZV were the most frequent aetiological agents in both databases with similar rates.Listeria monocytogenesandMycobacterium tuberculosiswere less frequent in PMSI than in the study (Listeria: 2%vs.5%,P = 0·001;Mycobacterium: 2%vs.8%,P < 0·001). The case-fatality ratios were similar, except forListeria(46% in the studyvs.16%). Nevertheless, despite the absence of case definitions and a possible misclassification weakening PMSI data, we suggest that PMSI may be used as a basic surveillance tool at a limited cost.
The Minnesota Center for Twin and Family Research Genome-Wide Association Study
Authors: Miller Michael B. , Basu Saonli , Cunningham Julie , Eskin Eleazar , Malone Steven M. , Oetting William S. , Schork Nicholas , Sul Jae Hoon , Iacono William G. , McGue Matt
Published: November 2012

As part of the Genes, Environment and Development Initiative, the Minnesota Center for Twin and Family Research (MCTFR) undertook a genome-wide association study, which we describe here. A total of 8,405 research participants, clustered in four-member families, have been successfully genotyped on 527,829 single nucleotide polymorphism (SNP) markers using Illumina's Human660W-Quad array. Quality control screening of samples and markers as well as SNP imputation procedures are described. We also describe methods for ancestry control and how the familial clustering of the MCTFR sample can be accounted for in the analysis using a Rapid Feasible Generalized Least Squares algorithm. The rich longitudinal MCTFR assessments provide numerous opportunities for collaboration.
Reflections on Twin Relationships: Twins Reared Apart and Twins of Opposite Sex / Research Reviews: Second Language Acquisition; Twin Research on Political Behavior; Twinning Rate in Cândido Godói / Human Interest: Twin ‘Cousins’ Separated at Birth; Chinese Quadruplets; Genetic Testing; KÀ (Cirque du Soleil)
Authors: Segal Nancy L.
Published: November 2012

The complexities of twin relationships posed by separate rearing and by opposite sex are considered. Unusual cases may highlight unique social-interactional processes and outcomes occurring in these pairs. Research reviews include recent twin studies on second language acquisition, political behavior, and multiple birth rates. Items of more general interest include twin ‘cousins’ reared apart, indistinguishable monozygotic quadruplets, a genetic testing dilemma, and a performance about separated twins.
Seismic evidence for the stratified lithosphere in the south of the North China Craton
Authors: Wang Pan , Xu Mingjie , Wang Liangshu , Mi Ning , Yu Dayong , Li Hua , Li Cheng , Bao Xuewei , Huang Tao , Huang Hui
Published: November 2012

The North China Craton (NCC) formed in the Paleoproterozoic and suffered cratonic destruction in the Mesozoic. It consists of the Western NCC (WNCC), the Trans‐North China Orogen (TNCO) and the Eastern NCC (ENCC). We investigated the upper mantle structures in the southern NCC by using receiver functions analysis. Polarization analysis was applied to increase the quality of receiver functions. The seismic images show significant stratified structures in the upper mantle in the south of the NCC. In the south of the WNCC, the lithosphere is ~280 km thick and contains a low‐velocity zone at ~110–220 km depth. This low‐velocity zone is interpreted as an intracratonic partial melting zone. In the south of the TNCO and ENCC, there is a low‐velocity zone at ~60–200 km depth, which results from the partial melting during the Mesozoic cratonic destruction. Its upper boundary is interpreted as new Lithosphere‐Asthenosphere Boundary at ~60–100 km depth. Below this low‐velocity zone, there are the remains of Archean lithosphere (RAL). Blocks of RAL stagnate in the asthenosphere and reach depths over 300 km. A high‐velocity slab extends from the uppermost mantle of the WNCC into the RAL with a dip‐angle of ~20°. This slab is interpreted as the Paleoproterozoic slab, which indicates an eastward subduction between the WNCC and the ENCC. The WNCC is stable. The lithosphere in the south of the TNCO and ENCC suffered the Mesozoic cratonic destruction, while the destruction is relatively weaker than that in the north of the ENCC.
Storage change in a flat‐lying fracture during well tests
Authors: Murdoch Lawrence C. , Germanovich Leonid N.
Published: November 2012

The volume of water released from storage per unit head drop per volume of an REV is a basic quantity in groundwater hydrology, but the details of the process of storage change in the vicinity of a well are commonly overlooked. We characterize storage change in a flat‐lying fracture or thin sedimentary bed through the apparent hydraulic compliance,Cf, the change in aperture of the fracture or thickness of the layer per unit change in pressure. The results of theoretical analyses and field measurements show thatCfincreases with time near the well during pumping, but it drops suddenly and may become negative at the beginning of recovery during a well test. Profiles ofCfincrease with radial distance from a well, but they are marked by a sharp increase and a sharp decrease at the edge of the region affected by the wellbore pressure transient. The conventional view in groundwater hydrology is that storage change at a point is proportional to the local change in pressure, which requires that the hydraulic compliance is uniform and constant. It appears that this conventional view is a simplification of a process that varies in both space and time and can even take on negative values. This simplification may be a source of uncertainty when interpreting well tests and extensometer records or predicting long‐term well performance.
Observed increases in Bering Strait oceanic fluxes from the Pacific to the Arctic from 2001 to 2011 and their impacts on the Arctic Ocean water column
Authors: Woodgate Rebecca A. , Weingartner Thomas J. , Lindsay Ron
Published: November 2012

Mooring data indicate the Bering Strait throughflow increases ∼50% from 2001 (∼0.7 Sv) to 2011 (∼1.1 Sv), driving heat and freshwater flux increases. Increase in the Pacific‐Arctic pressure‐head explains two‐thirds of the change, the rest being attributable to weaker local winds. The 2011 heat flux (∼5 × 1020J) approaches the previous record high (2007) due to transport increases and warmer lower layer (LL) temperatures, despite surface temperature (SST) cooling. In the last decade, warmer LL waters arrive earlier (1.6 ± 1.1 days/yr), though winds and SST are typical for recent decades. Maximum summer salinities, likely set in the Bering Sea, remain remarkably constant (∼33.1 psu) over the decade, elucidating the stable salinity of the western Arctic cold halocline. Despite this, freshwater flux variability (strongly driven by transport) exceeds variability in other Arctic freshwater sources. Remote data (winds, SST) prove insufficient for quantifying variability, indicating interannual change can still only be assessed by in situ year‐round measurements.
Quantifying the sources of spread in climate change experiments
Authors: Geoffroy O. , Saint‐Martin D. , Ribes A.
Published: November 2012

Energy‐balance models (EBM) constitute a useful framework for summarizing the first‐order physical properties driving the magnitude of the global mean surface air temperature response to an externally imposed radiative perturbation. Here the contributions of these properties to the spread of the temperature responses of an ensemble of coupled Atmosphere‐ocean General Circulation Models (AOGCM) of the fifth phase of the Coupled Model Intercomparison Project (CMIP5) are evaluated within the framework of a state‐of‐the‐art EBM. These partial contributions are quantified (in equilibrium and transient conditions) using the analysis of variance method. The radiative properties, particularly the strength of the radiative feedback to the global equilibrium surface warming, appear to constitute the most primary source of the spread. Moreover, the adjusted radiative forcing is found to play an important role in the spread of the transient response.
Human influence on extratropical Southern Hemisphere summer precipitation
Authors: Fyfe J. C. , Gillett N. P. , Marshall G. J.
Published: November 2012

Observations of extratropical Southern Hemisphere austral summer precipitation over recent decades show mid‐latitude drying and high‐latitude moistening. Here we show that the observed precipitation trends in two datasets are inconsistent with simulated internal variability, but are closely consistent with trends simulated in response to historical changes in anthropogenic and natural forcings. Simulations with individual anthropogenic and natural forcings suggest that the observed pattern of precipitation change is substantially forced by anthropogenic greenhouse gas and ozone changes, with an opposing influence from aerosols. Our results demonstrate that human influence had a significant impact on precipitation across the mid and high latitudes of the Southern Hemisphere, changes which are expected to have a profound impact on Southern Ocean stratification and hence on ocean‐atmosphere heat and carbon fluxes.
Giant flux ropes observed in the magnetized ionosphere at Venus
Authors: Zhang T. L. , Baumjohann W. , Teh W. L. , Nakamura R. , Russell C. T. , Luhmann J. G. , Glassmeier K. H. , Dubinin E. , Wei H. Y. , Du A. M. , Lu Q. M. , Wang S. , Balikhin M.
Published: November 2012

The Venus ionospheric response to solar and solar wind variations is most evident in its magnetic field properties. Early Pioneer Venus observations during the solar maximum revealed that the Venus ionosphere exhibits two magnetic states depending on the solar wind dynamic pressure conditions: magnetized ionosphere with large‐scale horizontal magnetic field; or unmagnetized ionosphere with numerous small‐scale thin structures, so‐called flux ropes. Here we report yet another magnetic state of Venus' ionosphere, giant flux ropes in the magnetized ionosphere, using Venus Express magnetic field measurements during solar minimum. These giant flux ropes all have strong core fields and diameters of hundreds of kilometers, which is about the vertical dimension of the ionosphere. This finding represents the first observation of these giant flux ropes at Venus. The cause of these giant flux ropes remains unknown and speculative.
The great Arctic cyclone of August 2012
Authors: Simmonds Ian , Rudeva Irina
Published: November 2012

On 2 August 2012 a dramatic storm formed over Siberia, moved into the Arctic, and died in the Canadian Arctic Archipelago on 14 August. During its lifetime its central pressure dropped to 966 hPa, leading it to be dubbed ‘The Great Arctic Cyclone of August 2012’. This cyclone occurred during a period when the sea ice extent was on the way to reaching a new satellite‐era low, and its intense behavior was related to baroclinicity and a tropopause polar vortex. The pressure of the storm was the lowest of all Arctic August storms over our record starting in 1979, and the system was also the most extreme when a combination of key cyclone properties was considered. Even though, climatologically, summer is a ‘quiet’ time in the Arctic, when compared withall Arctic storms across the period it came in as the 13th most extreme storm, warranting the attribution of ‘Great’.
On the robustness of tropospheric adjustment in CMIP5 models
Authors: Kamae Youichi , Watanabe Masahiro
Published: November 2012

Effective radiative forcing associated with the tropospheric adjustment (TA) caused by atmospheric CO2 quadrupling (4×CO2) is quantified using fixed sea surface temperature experiments in CMIP5 models. Several features of TA in the tropics, partly related to weakening of the hydrological cycle, are found robust among the models: warming and drying of the free troposphere, near‐surface moistening, strengthened stability in the lower troposphere, reduction in total cloud amount and shortwave cloud radiative effect (SWcld) over oceans. A positive SWcldchange prevailing in the tropical subsidence regime gives rise to large uncertainty in total effective radiative forcing, and is regulated quantitatively by changes in relative humidity (RH) that measure cloud decrease in the lower troposphere. A robust tropospheric warming primarily explains the RH decrease in the lower troposphere, but the change in specific humidity is largely model‐dependent, which contributes to the inter‐model spread of TA.
Geomagnetic conjugate observations of plasma‐sheet electrons by the FAST and THEMIS satellites
Authors: Lee S. , Shiokawa K. , McFadden J. P. , Seki K.
Published: November 2012

We investigate pitch‐angle distributions and spectral shapes of auroral electrons simultaneously observed during three conjunction events by the FAST satellite at altitudes of 2500–3500 km and by the THEMIS satellite in the plasma sheet at 7–13 RE. All three events were on the lower latitude of the auroral oval. Conjunction event 1 occurred at ~1914:45 UT on 10 April 2008. Electron spectra at energies of 0.1–3 keV are correlated well between the two satellites, while the precipitating electrons above 3 keV are missing at FAST. Event 2 occurred at 1255:26 UT on 26 April 2008. Electron spectra above 3 keV are correlated well between the two satellites. An additional broad spectral peak at energies of 0.1–0.5 keV was observed by FAST. Event 3 occurred at 0058:04 UT on 25 December 2008. Precipitating electrons of 0.5–5 keV obtained by FAST are correlated well with those of THEMIS‐C, while a monoenergetic peak at 0.1–0.2 keV was observed only by FAST. For the three conjunction events, we conclude that high‐energy precipitating auroral electrons observed by FAST directly come from the equatorial plasma sheet, while low‐energy precipitating electrons may come from middle altitudes as a result of acceleration by static potential differences. For missing high‐energy (>3 keV) electrons of event 1, we speculate that the pitch‐angle scattering by waves occurs only at a limited energy range.
Ground and satellite observations of low‐latitude red auroras at the initial phase of magnetic storms
Authors: Shiokawa K. , Miyoshi Y. , Brandt P. C. , Evans D. S. , Frey H. U. , Goldstein J. , Yumoto K.
Published: November 2012

We report ground and satellite observations of unique low‐latitude red auroras that appear at the initial phase of geomagnetic storms. For two events on 21 October 2001, and 6 April 2000, the low‐latitude red auroras appeared at ~45° MLAT (L ∼ 2) ∼ 1.5 h after the storm sudden commencement in the postmidnight sector in Japan. Comprehensive satellite data were available for the former event. The energetic neutral atom images obtained by the Imager for Magnetopause‐to‐Aurora Global Exploration satellite show rapid enhancement of ring current hydrogen and oxygen fluxes at radial distances of ∼ 2–8 RE after the storm sudden commencement and associated with several storm‐time substorms. The hydrogen ring‐current enhancement occurred particularly in the postmidnight sector where the red aurora was observed. The timing of oxygen flux enhancement associated with a storm‐time substorm coincided with the red aurora appearance. This rapid and significant enhancement of energetic neutral atom flux was also confirmed by energetic ion data obtained by the NOAA/POES‐16 satellite. Extreme ultraviolet plasmaspheric images obtained by Magnetopause‐to‐Aurora Global Exploration indicate that the plasmapause was located at L = 2.3–2.5 in the postmidnight sector during the event, indicating that a spatial overlap occurs between the plasmasphere and the enhanced ring current ions at L ∼ 2. Based on these observations, we suggest that large energization of high‐energy ring‐current ions in the postmidnight inner magnetosphere caused the spatial overlap of these ring‐current ions with the low‐energy plasmaspheric plasmas at L ∼ 2, producing the low‐latitude red auroras at the very beginning of the storms.
On the nature of low‐latitude Es influencing the genesis of equatorial plasma bubble
Authors: Joshi L. M. , Patra A. K. , Pant T. K. , Rao S. V. B.
Published: November 2012

The potential influence of the postsunset low‐latitude sporadic E (Es) on the genesis of equatorial plasma bubble (EPB) has been investigated using observations made with the Gadanki radar and two ionosondes, one located at the magnetic equator providing the F layer characteristics and another at magnetically low‐latitude providing the Es parameters. Observations revealed that the occurrence of EPB was associated with either the disruption of Es or presence of nonblanketing‐type Es or intermittently occurring blanketing Es at low‐latitude. In contrast, when blanketing Es occurred for a relatively long duration in the sunset hours, EPB did not occur. Model computation clearly reveals that the growth of the Rayleigh‐Taylor instability depends very much on the thickness, height, and shape of electron density profile of the Es layer. The above findings thus suggest that low‐latitude Es variability plays decisive role on the day‐to‐day variability of EPB through the growth rate of the Rayleigh‐Taylor instability.
East‐west differences inF‐region electron density at midlatitude: Evidence from the Far East region
Authors: Zhao Biqiang , Wang Min , Wang Yungang , Ren Zhipeng , Yue Xinan , Zhu Jie , Wan Weixing , Ning Baiqi , Liu Jing , Xiong Bo
Published: November 2012

The global configuration of the geomagnetic field shows that the maximum east‐west difference in geomagnetic declination of northern middle latitude lies in the US region (~32°), which produces the significant ionospheric east‐west coast difference in terms of total electron content first revealed by Zhang et al. (2011). For verification, it is valuable to investigate this feature over the Far East area, which also shows significant geomagnetic declination east‐west gradient but smaller (~15°) than that of the US. The current study provides evidence of the longitudinal change supporting the thermospheric zonal wind mechanism by examining the climatology of peak electron density (NmF2), electron density (Ne) of different altitudes in the Far East regions with a longitude separation of up to 40–60° based on ground ionosonde and space‐based measurements. Although the east‐west difference (Rew) over the Far East area displays a clear diurnal variation similar to the US feature, that is negativeRew(West Ne > East Ne) in the noon and positive at evening‐night, the observational results reveal more differences including: (1) The noontime negativeRewis most pronounced in April–June while in the US during February–March. Thus, for the late spring and summer period negativeRewover the Far East region is more significant than that of the US. (2) The positiveRewat night is much less evident than in the US, especially without winter enhancement. (3) The magnitude of negativeRewtends to enhance toward solar maximum while in the US showing anticorrelation with the solar activity. The altitude distribution of pronounced negative difference (300–400 km) moves upward as the solar flux increases and hence produces the different solar activity dependence at different altitude. The result in the paper is not simply a comparison corresponding to the US results but raises some new features that are worth further studying and improve our current understanding of ionospheric longitude difference at midlatitude.
Application of broadband alternating current magnetic susceptibility to the characterization of magnetic nanoparticles in natural materials
Authors: Kodama Kazuto
Published: November 2012

A new method is proposed for characterizing magnetic particles by measuring low‐field alternating current magnetic susceptibility at a number of frequency steps spanning four orders of magnitude, from 125 Hz to 512 kHz. This method was tested using natural samples with various grain size distributions, including basalt (Kilauea, Hawaii), loess and paleosol (Luochuan, China), tuff (Yucca Mountain, Nevada), granite (Minnesota Valley, Minnesota), and andesite (Sakurajima, Japan). The resulting frequency spectrum of magnetic susceptibility (FSMS) of the basalt, loess/paleosol, and tuff decreases with increasing frequency, but at different rates of decrease. The FSMS of the basalt is characterized by a monotonic decrease with increasing frequency over the entire range. The FSMS of the loess/paleosol and the tuff decreases more markedly than that of the basalt, which agrees with previous results showing that superparamagnetic particles are dominant in such material. Quantitative estimates using FSMSs allow reconstruction of characteristic grain size distributions and clearly identify differences in the distribution of superparamagnetic particles. The multidomain granite sample has no distinct frequency dependence, which is probably due to the smooth displacement of domain walls in the presence of the external field. In contrast, the FSMSs of the andesite samples exhibit maxima over a limited frequency range, between 16 and 128 kHz. This behavior, together with low‐temperature measurements, can be accounted for by magnetic resonance of domain walls in the multidomain phenocrysts.
From the subtropics to the central equatorial Pacific Ocean: Neodymium isotopic composition and rare earth element concentration variations
Authors: Grenier Mélanie , Jeandel Catherine , Lacan François , Vance Derek , Venchiarutti Célia , Cros Alexandre , Cravatte Sophie
Published: November 2012

Neodymium isotopic compositions (εNd) and rare earth element (REE) concentrations were measured for filtered surface to deep waters (112 samples) in the Southern Tropical Pacific. The relatively detailed picture of these tracer distributions allowed us to refine the areas where oceanic εNd variations occur. εNd values increase for most of the water masses flowing from Samoa to the Solomon Sea and in the Papua New Guinea (PNG) area, as already observed. Furthermore, water masses arriving from the eastern equatorial Pacific (200–550 m depth) also revealed radiogenic values, possibly acquired in the vicinity of the South American coasts and Galapagos Islands. These εNd variations affect the whole water column. The most likely process causing such variations is “boundary exchange” between the numerous radiogenic slopes/margins located in this area and seawater flowing past. Dissolution of atmospheric deposition and/or diffuse streaming of volcanic ash are also suggested to explain the radiogenic εNd observed at the surface in the PNG area. Interestingly, a positive europium (Eu) anomaly characterizes the normalized REE patterns of most of the studied water masses. This anomaly is consistent with the REE patterns of sediment and rock samples that are potential sources for the local waters. Such consistency reinforces the hypothesis that lithogenic sources play a major role in the oceanic REE budget, thanks to “boundary exchange.” The data set presented here is a good basis for further sampling that will be realized in the framework of the ongoing GEOTRACES program (www.geotraces.org).
Fine‐particle emissions from solid biofuel combustion studied with single‐particle mass spectrometry: Identification of markers for organics, soot, and ash components
Authors: Pagels Joakim , Dutcher Dabrina D. , Stolzenburg Mark R. , McMurry Peter H. , Gälli Markus E. , Gross Deborah S.
Published: November 2012

The effects of combustion phase and fuel on smoke particle emissions from a wood stove operated with three different wood fuels and from a corn stove were investigated. A single‐particle mass spectrometer (aerosol time of flight mass spectrometer (ATOFMS)) was used for time‐ and size‐resolved chemical signatures and a scanning mobility particle sizer (SMPS) was used for online mobility size distributions. Markers of particle phase organics and elemental carbon, PM1.5, and CO emissions were strongly reduced for the corn stove compared to the wood stove. This is because the more controlled fuel and air supply in the corn stove result in more complete combustion. NOx emissions and particle phase phosphates showed the opposite trend. Marker ions and particle types associated with soot and alkali salts such as potassium chloride and potassium sulfates dominated during flaming combustion and were correlated with increased exhaust temperatures and reduced CO emissions. Marker ions of hydrocarbons and oxidized organics as well as a particle cluster type with a strong organic signature were associated with reduced combustion temperature and increased CO levels, observed during start up from cold stove, addition of fuel, and combustion with reduced air supply. Two different particle types were identified in corn experiments when particles were classified according to mobility before they were measured with the ATOFMS. “Less massive” particles contained mostly ash and soot and had vacuum aerodynamic diameters that were nearly independent of mobility diameter. “More massive” particles had aerodynamic diameters that increased linearly with mobility diameter, indicating approximately spherical shapes, and were hypothesized to consist of organics.