bluuebunny/crossref_metadata_2025 huggingface dataset:
Percutaneous versus Conventional Tracheostomy in Burned Patients with Inhalation Injury
Authors: Gravvanis Andreas I. , Tsoutsos Dimosthenis A. , Iconomou Thomais G. , Papadopoulos Stefanos G.
Published: November 2005

The aim of the study was to compare conventional tracheostomy with percutaneous dilatational tracheostomy in patients with inhalation burn injury. A total of 37 patients with severe burn injuries and associated inhalation injury, underwent percutaneous tracheostomy in our burn unit and were retrospectively compared with 22 patients who underwent conventional surgical tracheostomy. In the first group, 25 of 37 patients and in the second group 17 of 22 patients presented with partial or full‐thickness burn injuries (or both) in the neck region. The cost of the procedure, operating time, complications, and incidence of pulmonary infection were recorded. There were no significant perioperative complications in the percutaneous tracheostomy group, and no patient required surgical revision or conversion to surgical tracheostomy. In the conventional tracheostomy group, 2 patients developed tracheal stenosis, 1 had a tracheoesophageal fistula, and 10 had stomal infections. The average procedure time in the first group was 9 minutes, and in the second group it was 22 minutes. The cost of the bedside percutaneous tracheostomy was one‐fifth the cost of a conventional tracheostomy. The incidence of pulmonary sepsis was 45% after percutaneous tracheostomy compared to 68% after conventional tracheostomy. With the percutaneous technique, spontaneous closure of the stoma occurred within 1 to 3 days after removal of the tracheostomy tube, whereas with the conventional technique it was within 5 to 7 days. Percutaneous tracheostomy is associated with a lower complication rate and can be safely performed at the bedside. Moreover, it is faster and can be done at a lower cost than conventional open tracheostomy.
Incisional Hernia: Early Complication of Abdominal Surgery
Authors: Burger Jacobus W.A. , Lange Johan F. , Halm Jens A. , Kleinrensink Gert‐Jan , Jeekel Hans
Published: November 2005

It has been suggested that early development of the incisional hernia is caused by perioperative factors, such as surgical technique and wound infection. Late development may implicate other factors, such as connective tissue disorders. Our objective was to establish whether incisional hernia develops early after abdominal surgery (i.e., during the first postoperative month). Patients who underwent a midline laparotomy between 1995 and 2001 and had had a computed tomography (CT) scan of the abdomen during the first postoperative month were identified retrospectively. The distance between the two rectus abdominis muscles was measured on these CT scans, after which several parameters were calculated to predict incisional hernia development. Hernia development was established clinically through chart review or, if the chart review was inconclusive, by an outpatient clinic visit. The average and maximum distances between the left and right rectus abdominis muscles were significantly larger in patients with subsequent incisional hernia development than in those without an incisional hernia (P < 0.0001). Altogether, 92% (23/25) of incisional hernia patients had a maximum distance of more than 25 mm compared to only 18% (5/28) of patients without an incisional hernia (P < 0.0001). Incisional hernia occurrence can thus be predicted by measuring the distance between the rectus abdominis muscles on a postoperative CT scan. Although an incisional hernia develops within weeks of surgery, its clinical manifestation may take years. Our results indicate perioperative factors as the main cause of incisional hernias. Therefore, incisional hernia prevention should focus on perioperative factors.
Impact of predation by a cave‐dwelling bat,Rhinolophus ferrumequinum, on the diapausing population of a troglophilic moth,Goniocraspidum preyeri
Authors: Sano Akira
Published: November 2005

The predation pressure of the greater horseshoe bat,Rhinolophus ferrumequinum, on the diapausing population of the noctuid moth,Goniocraspidum preyeri, was examined at an abandoned mine in central Japan. These bats did not prey on the moths in summer. The number of moths preyed on was largest in March. More than 60% of the diapausing moths were eaten by only three or four bats, which accounted for over 90% of all the moth deaths. This moth was an important source of food at the end of the hibernating period when the bat had already used most of its stored subcutaneous fat. The predation onG. preyerimay have raised the overwintering success rate ofR. ferrumequinum.
Interactions between mycorrhizal colonization and plant life forms along the successional gradient of coastal sand dunes in the eastern Mediterranean, Turkey
Authors: Çakan Halil , Karataş Çiğdem
Published: November 2005

The mycorrhizal status of dune plant species in relation to their plant life forms was surveyed along a successional gradient of sand dune on the southern Mediterranean coast of Turkey. Roots of 64 dune plant species belonging to 30 families were collected from sand dune communities at four different successional stages: embryonic dunes (ED), mobile dunes (MD), fixed dunes (FD), and remnant dunes (RD). Of the plant species surveyed in all successional stages, 54 (84%) had formed mycorrhizal associations. Nonmycorrhizal plants with cryptophyte life forms predominated in the earlier successional stages (ED and MD), whereas the number and percent coverage of mycorrhizal plant species belonging to hemicryptophytes, phanerophytes, and chamaephytes generally increased with the stabilization of sand dunes. Arbuscular mycorrhizal (AM) colonization was found to be the dominant mycorrhizal type in ED, MD, and RD. But phanerophytes with dual colonization, AM and ectomycorrhizal, became the dominant life form with high plant coverage in the FD stage. Total percentage of mycorrhizal root length colonization showed significant positive correlations relating to soil parameters such as organic matter and nitrogen content, while negatively correlating to high soil reaction (pH).
Evolutionary characteristics of the artificially revegetated shrub ecosystem in the Tengger Desert, northern China
Authors: Wang Xin‐Ping , Li Xin‐Rong , Xiao Hong‐Lang , Pan Yan‐Xia
Published: November 2005

The rain‐fed sand‐binding vegetation which stabilizes the migrating desert dunes in the Shapotou area at the southeastern edge of the Tengger Desert was initiated in 1956. The shrubs initially employed were predominantly Caragana korshinskii, Hedysarum scoparium, and Artemisia ordosica, and a desert shrub ecosystem with a dwarf shrub and microbiotic soil crust cover on the stabilized sand dunes has since developed. Since 1956 the success of this effort has not only ensured the smooth operation of the Baotou–Lanzhou railway in the sand dune area but has also played an important role in the restoration of the local eco‐environment; therefore, it is viewed as a successful model for desertification control and ecological restoration along the transport infrastructure in the arid desert region of China. Some of the effects of recovery from desertification and ecological restoration on soil properties are shown by the increase in the distribution of fine soil particles, organic matter, and nutrients. The physical surface structure of the stabilized sand dunes, and inorganic soil crusts formed by atmospheric dust, have also led to the gradual formation of microbiotic soil crusts. Sand dune stabilization is associated with: (1) decreased soil particle size, (2) increased total N, (3) increased thickness of microbiotic crusts, (4) increased thickness of subsoil, and (5) an increase in volumetric soil moisture in the near‐surface environment. After 17 years of dune stabilization, both the number of shrubs and community biomass decreased. The number of microbes, plant species and vegetation cover, all attained a maximum after the dunes had stabilized for 40 years. There is a significant positive correlation between the fractal dimension of soil particle size distribution (PSD) and the clay content of the shallow soil profile in the desert shrub ecosystem; the longer the period of dune stabilization, the greater the soil clay content in the shallow soil profiles (0–3 cm), and the greater the fractal dimension of soil PSD. This reflects the fact that during the revegetation processes, the soil structure is better developed, especially in the upper profile. Hence, the migrating sand dune becomes more stabilized. Therefore, the fractal model can be used to describe the texture and fertility of the soil, and, along with the degree of stability of the previously migrating sand dunes, can be used as an integrated quantitative index to evaluate the revegetation practice in the sand dune areas and their stabilization.
Dust and self-similarity for the Smoluchowski coagulation equation
Authors: Escobedo M. , Mischler S.
Published: November 2005

Smoluchowski coagulation equation for a class of homogeneous coagulation rates of degree

\lambda \in [0,2)

. On the one hand for any initial datum

f_{\mathrm{in}} \in \dot{L}_1^1

we build a weak solution which conserves the mass when

\lambda \leq 1

and loses mass in finite time (gelation phenomenon) when

\lambda > 1

. We then extend this existence result to a measure framework allowing dust source term. In that case we prove that the income dust instantaneously aggregates and the solution does not contain dust phase. On the other hand, we investigate the qualitative properties of self-similar solutions to the Smoluchowski's coagulation equation when

\lambda < 1

. We prove regularity results and sharp uniform small and large size behaviour for the self-similar profiles.

Nous considérons l'équation de Smoluchowski pour une classe de taux homogènes de degré

\lambda \in [0,2)

. D'une part, pour toute donnée initiale

f_{\mathrm{in}}\in \dot{L}_1^1

nous construisons une solution qui conserve la masse lorsque

\lambda \leq 1

et qui perd de la masse en temps fini (phénomène de gélification) lorsque

\lambda > 1

. Nous étendons ensuite ce résultat à un contexte mesure qui permet de prendre en compte un terme de source « poussière ». Dans ce cas, nous démontrons que la poussière entrant dans le système s'agglomère instantanément et que la solution ne contient pas de phase poussière. D'autre part, nous étudions les propriétés qualitatives des solutions auto-similaires lorsque

\lambda < 1

. Nous démontrons des résultats de régularité et établissons des estimations uniformes sur le comportement du profil auto-similaire pour les petites et les grandes tailles de particules.
Mrg19 depletion increases S. cerevisiae lifespan by augmenting ROS defence
Authors: Kharade Sujay V. , Mittal Nitish , Das Shankar P. , Sinha Pratima , Roy Nilanjan
Published: November 2005

Caloric restriction (CR) is the most compelling example of lifespan extension by external manipulation. Although the molecular mechanisms remain unknown, the theory of hormesis has been invoked to explain the life promoting effects of CR. Hormesis is defined as the beneficial effects of low intensity stressor on a cell or organism. Mrg19 is a putative transcription factor that regulates carbon and nitrogen metabolism in yeast. In this study, we have found that deletion of MRG19 gene causes metabolic shift in yeast cells, leading to higher intracellular reactive oxygen species, augmentation of scavenging enzymes and longer lifespan compared to wild‐type cells. All these results together suggest that similar to CR, depletion of Mrg19 leads to a condition of mild stress which in turn enhances vitality.
Fine structure of the anterior adhesive apparatus (head organs) of Bravohollisia gussevi Lim, 1995 (Monogenea: Ancyrocephalidae)
Authors: WONG W. L. , BRENNAN G. P. , HALTON D. W. , LIM L. H. S.
Published: November 2005

A study of the anterior adhesive apparatus (head organs) of Bravohollisia gussevi Lim, 1995 was carried out using light and electron microscopy. The anterior adhesive apparatus or head organs in B. gussevi comprise 6 circular openings or apertures in the antero-lateral region, associated pits lined with specialized microvillous tegument that differ from the general body tegument, a bundle of ducts, and uninucleate gland cells located lateral to the pharynx. The uninucleate glands of the anterior adhesive apparatus (head organs) comprise 2 types of cells, one kind of cell producing rod-like bodies (S1) and the other oval bodies (S2). The S1 bodies are filled with numerous, less electron-dense vesicles in an electron-dense matrix, while S2 bodies have no vesicles but contain a more homogeneous electron-dense matrix. Interlinking band-like structures were observed between S1 bodies. Similar band-like structures were found between S2 bodies. The formation of S1 bodies was followed by transmission electron microscopy. However, the formation of S2 bodies was unclear and could not be resolved. Uniciliated structures were also observed around the openings of the anterior adhesive apparatus. Each uniciliated structure is usually associated with an opening of a gland cell producing granular, electron-dense, secretory bodies, which differ from the secretions produced by the lateral gland cells of the anterior adhesive apparatus.
Robert Rodgers Korstad,Civil Rights Unionism: Tobacco Workers and the Struggle for Democracy in the Mid-Twentieth-Century South. Chapel Hill: University of North Carolina Press, 2003. 576 pp. $55.00 cloth, $24.95 paper.
Authors: Helgeson Jeffrey
Published: November 2005

Robert Rodgers Korstad's dramatic story of tobacco workers in Winston-Salem, North Carolina, during the 1940s and 1950s, reveals the intricate connections between a local struggle for better wages and working conditions and the broader fight for racial democracy and civil rights. On June 17, 1943, a group of black women at the Reynolds Tobacco plant stopped work, rejecting the authority of a dictatorial white foreman and expressing long-simmering anger over speed-ups, dangerous working conditions, and unjust wages. With the help of organizers from the left-leaning United Cannery, Agricultural, Packing, and Allied Workers of America (UCAPAWA), hundreds of black (and a few white) workers at Reynolds built Local 22 of the Food, Tobacco, Agricultural, and Allied Workers of America (FTA-CIO). Korstad eloquently tells us how the FTA succeeded. He points to the temporary convergence of factors, an active federal government in labor relations, the labor movement's aggressive Southern Front, and the move in the urban South toward white supremacy with “a lighter touch” (376) that created a moment of extraordinary opportunity for “working-class blacks [who], through their participation in the labor movement, were in the vanguard of civil rights efforts of the 1940s.”(422)
Editorial
Authors: THOMPSON JUNE
Published: November 2005

Given the continuing pressures on academics to publish their research work in high quality publications,
we find that authors are required to provide their institutions with increasingly more detailed information about the journals
in which their papers appear. One frequently asked question relates to rejection rates. On average, fewer than fifty per cent
of papers submitted to ReCALL are accepted. For example, in the current year 2005, 45 papers were submitted, of which 16 were
published.
A closer look at blended learning — parameters for designing a blended
learning environment for language teaching and learning
Authors: NEUMEIER PETRA
Published: November 2005

In the course of designing, writing and implementing CALL-supported material, it has become evident
to me that a systematic investigation into the factors that shape the Blended Learning (BL) experience in the context of
language learning and teaching is missing and urgently needed. The core question when designing a BL environment is:
Which combination of modes provides the optimal basis for language learning and teaching given the particular conditions at
hand? In order to tackle this question, course designers need a framework of parameters that help them decide on the individual,
context-related implementation of BL. It is the purpose of this paper to put forward a definition of BL and a framework of
parameters for designing a BL environment. In order to achieve a better understanding of the factors that shape the
practice and the experience of BL, the main parameters which form a BL environment will be listed and specified.
These parameters evolved from the experience of designing Jobline LMU (www.jobline.lmu.de) and will hopefully prove to be
helpful for the process of designing other BL environments. If applied successfully, the idea of BL could serve as a
bridge between the broader community of language teachers and learners and CALL experts and practitioners. BL offers the
potential of broadening the scope and influence of CALL and of (re-)establishing it as an innovative component of general
language teaching.
Blended learning in a teacher training course: Integrated interactive e-learning and
contact learning
Authors: KUPETZ RITA , ZIEGENMEYER BIRGIT
Published: November 2005

The paper discusses a blended learning concept for a university teacher training course for prospective
teachers of English. The concept aims at purposeful learning using different methods and activities, various traditional and
electronic media, learning spaces covering contact and distance learning, and task-based learning modules that begin with
multimedia-based case stories. The learning concept is based on theories of situated learning in multimedia-enhanced learning
environments. The activities discussed include classroom recordings and multimedia-based case stories, an electronic interview
with an expert who is an experienced grammar school teacher, and mini-practices, which implement micro teaching in a classroom
setting. Case stories used as a didactic tool in teacher education are supposed to contribute to a closer and more reflective
relationship between theory-driven and practically-oriented aspects of teacher education. The multimedia-based case stories
are hypertexts designed as essential components of computer-based learning modules that support various ways and styles of
learning. Students worked with the case story material either in guided or in self-regulated scenarios several times during
the course. Three types of learners could be distinguished: students who mainly create and apply experiences, students who
mainly study the theoretical resources, and students who create with focused selection of resources. The e-interview
promotes an exchange between theory and practical teaching and experience with this format of e-learning at the same time.
The mini-practice offers guided insights into analyzing teaching materials, hands-on experiences with lesson planning and
the experience of acting as a teacher in an authentic teaching context. Furthermore, the mini-practice is meant to help
the students broaden their perspectives on “English lessons at
school” and change their perspective, that is, from a pupil’s to
a prospective teacher’s. These activities combine contact learning and interactive e-learning. This combination is
highly appreciated by our learners and represents our concept of integrated interactive e-learning and contact learning.
Can it be as effective? Distance versus blended learning in a web-based EAP programme
Authors: HARKER MIHYE , KOUTSANTONI DMITRA
Published: November 2005

This paper discusses the effectiveness of a web-based learning programme of English for Academic Purposes (EAP)
for British students from ethnic minority backgrounds. Original web-based materials for English for Academic Purposes (EAP)
were developed and 43 student volunteers participated in two different modes of learning during the 9-week long programme:
through blended learning and at a distance. The study attempts to investigate which mode of delivery is more effective in terms
of student retention, achievement levels and satisfaction with the programme. The study found that the blended learning mode
was much more effective in student retention in this non-credit bearing programme,
whilst students’ achievement levels were similar in both groups. In addition, formative and summative feedback
from the students suggests that most students in both groups were satisfied with this web-based EAP programme.
CASLA through a social constructivist perspective: WebQuest in project-driven language learning
Authors: SIMINA VASSILIKI , HAMEL MARIE-JOSÉE
Published: November 2005

The basic tenet of constructivism is that learners construct their knowledge on their own by associating
new with prior information. The significance of the learner’s interaction with his/her social and physical environment is
here of great importance; the learner is at the center of the learning process while the tutor is seen as a facilitator, a guide.
Considering the paradigm shift in education and language learning, the assumptions of the constructivist philosophy encourage
the use of computers in second language acquisition. Computer technology is capable of providing the context for collaboration
and social interaction in which learners will construct the knowledge of the target language on their own by being engaged in
meaningful activities. Moreover, computers allow learners to interact not only with the learning materials but also with other
people. The combination of the social and individual aspect is best expressed by social constructivism. Placing language learning
in a socio-cognitive context, we will approach second language acquisition from a social constructivist perspective and indicate
the value of such an approach for the design and evaluation of Computer Applications in Second Language Acquisition (CASLA).
Firstly, an overview of constructivism as a theory of learning is required in order to make clear the basic assumptions of the
constructivist theory. Secondly, the focus is placed on social constructivism which is examined in relation to second language
acquisition. This in tandem exploration will lead us to provide a framework which integrates all four language skills in a general
theoretical framework of social interaction and shows how social constructivism can promote second language acquisition. Finally,
one type of on-line application such as WebQuest, which is best developed in project-driven language learning, will be provided
as a potential example of good practice in approaching Computer Applications in Second Language Learning through a social
constructivist perspective.
CALL research archive: How can an online knowledge base further communication among second language professionals
Authors: HANSON JANE L. , DEMBOVSKAYA SVETLANA , LEE SOOJUNG
Published: November 2005

The inspiration for our project arose from a perceived gap between research in foreign/second language learning
and classroom practice. In order to address this issue, we created a web site
containing summaries of seminal articles in the area of CALL – computer assisted language learning. The summaries are useful
for many teachers who do not have time to read full text journal articles and understand the statistical terms, but would like to
take advantage of the research findings. Researchers will receive feedback from teachers in the form of comments, which may give
insight for further research. Other features of the website are: a database
of teachers' comments and demographic information,
keyword search, index, glossary, chronological and alphabetical bibliography, links to research archives and sites assisting with
statistical terminology and design of experiments.
In two minds? Learner attitudes to bilingualism and the bilingual tandem analyser
Authors: KAPEC PETER , SCHWIENHORST KLAUS
Published: November 2005

One of the issues that has been debated in the context of fairly open learning partnerships such as
tandem learning has been whether and, if so, how much pedagogical support should be provided. Another issue is how do
language learners who have grown accustomed to maximising their learning through comprehensible input and output make
the transition to a reciprocal learning partnership where they are supposed to switch between the roles of learner and
expert or resource. The three principles behind tandem learning are bilingualism; reciprocity; and learner autonomy. At
Trinity College Dublin we have conducted extensive research into tandem learning in object-oriented Multiple User Domains (MOOs)
since 1998. Of the three tandem principles, we found that balanced bilingualism, where both languages are used equally in the
exchange, is difficult to achieve, particularly though not surprisingly in partnerships where L2 proficiency differs substantially.
We think that technology, at least in MOOs, can contribute towards a solution to the problem. The bilingual tandem analyser (BTA)
analyses MOO input while users are communicating and gives feedback to learners (and possibly teachers) on bilingualism in the
exchange. Here, we discuss what attitudes towards bilingualism learners bring towards the tandem exchange and how they react
to the BTA as a tool to monitor and regulate bilingualism: will learners perceive balanced bilingualism as a necessary principle
of the partnership; what efforts do they make to keep the balance between the languages; how do they see the BTA: as an instrument
of control, directed by the teacher; or do they perceive it as a useful tool to support their tandem exchanges?
What do meta-analyses tell us about CALL effectiveness?
Authors: FELIX USCHI
Published: November 2005

A great deal of research has been carried out over the past two decades related to the effectiveness of
computer-assisted teaching and learning. This large body of work, however, has not produced unequivocal findings, especially in the
area of CALL. Our study takes a systematic look at what dedicated meta-research since 1991 might have contributed to this controversial
field. Data was gathered from several hundred studies including ca 20,000 subjects. The paper highlights the benefits and limitations
associated with this type of research, synthesizes findings and recommends models and strategies for future research in the context
of an agreed research agenda. Our synthesis suggests consistent positive findings related to L1 spelling, writing and reading. While
there is some support for this related to CALL per se, much work needs to be done before we might reach the levels of confidence
enjoyed by some of the findings reported here.
Virtual musical performance and improvisation on Internet2
Authors: HELMUTH MARA
Published: November 2005

Several projects involving audio and video transmission between the University of Cincinnati and other sites over the high bandwidth Internet2 have ranged from the simple transmission of video material, to more complex interactive improvisation. A performance of Clotho, the life of Camille Claudel, a musical monodrama collaboration, was streamed in September 2000 over Internet2 to a widely distributed audience. The second project involved my real-time contribution from Cincinnati to a performance happening at Yale University of The Ankle Diver, with music by Matthew Suttor. A network improvisation project with the Soundmesh (formerly Internet Sound Exchange) software resulted in a number of improvisations involving the University of Cincinnati, Columbia University, Yale University and the Fall Internet2 Meeting at the University of Southern California. High-quality audio and flexibility of sound sources and processing is a strength of these improvisations.
Contemporary crustal deformation around the southeast borderland of the Tibetan Plateau
Authors: Shen Zheng‐Kang , Lü Jiangning , Wang Min , Bürgmann Roland
Published: November 2005

We derive a detailed horizontal velocity field for the southeast borderland of the Tibetan Plateau using GPS data collected from the Crustal Motion Observation Network of China between 1998 and 2004. Our results reveal a complex deformation field that indicates that the crust is fragmented into tectonic blocks of various sizes, separated by strike‐slip and transtensional faults. Most notably, the regional deformation includes 10–11 mm/yr left slip across the Xianshuihe fault, ∼7 mm/yr left slip across the Anninghe‐Zemuhe‐Xiaojiang fault zone, ∼2 mm/yr right slip across a shear zone trending northwest near the southern segment of the Lancang River fault, and ∼3 mm/yr left slip across the Lijiang fault. Deformation along the southern segment of the Red River fault appears not significant at present time. The region south and west of the Xianshuihe‐Xiaojiang fault system, whose eastward motion is resisted by the stable south China block to the east, turns from eastward to southward motion with respect to south China, resulting in clockwise rotation of its internal subblocks. Active deformation is detected across two previously unknown deformation zones: one is located ∼150 km northwest of and in parallel with the Longmenshan fault with 4–6 mm/yr right‐slip and another is continued south‐southwestward from the Xiaojiang fault abutting the Red River fault with ∼7 mm/yr left slip. While both of these zones are seismically active, the exact locations of faults responsible for such deformation are yet to be mapped by field geology. Comparing our GPS results with predictions of various models proposed for Tibetan Plateau deformation, we find that the relatively small sizes of the inferred microblocks and their rotation pattern lend support to a model with a mechanically weak lower crust experiencing distributed deformation underlying a stronger, highly fragmented upper crust.
Seismicity in the incoming/subducting Philippine Sea plate off the Kii Peninsula, central Nankai trough
Authors: Obana Koichiro , Kodaira Shuichi , Kaneda Yoshiyuki
Published: November 2005

Along the Nankai trough, southwestern Japan, the Philippine Sea plate (PHS) is subducting beneath the Eurasian plate, and large interplate earthquakes have occurred repeatedly. The latest large thrust earthquake at the central Nankai trough off the Kii Peninsula was the 1944 Tonankai earthquake (Mw = 8.2). Although a previous ocean bottom seismograph (OBS) experiment from November 2001 to February 2002 showed seismicity around the rupture area of the 1944 Tonankai earthquake, there were large uncertainties regarding hypocenter locations, especially with respect to depth. We conducted another OBS experiment to obtain accurate locations of earthquakes and their focal mechanisms. The new results show earthquake clusters at the trough axis within the oceanic crust. The clusters were located near faults cutting the oceanic crust, and thus the earthquakes may have occurred along preexisting faults in the incoming PHS. Seismicity in the subducting PHS is characterized by seismic quiescence in the oceanic crust of the coseismic rupture area of the 1944 Tonankai earthquake. The change in seismicity in the oceanic crust can be explained by a change in the stress in the incoming, subducting PHS. The stress in the oceanic crust of the PHS changes from trough‐normal tension at the trough axis, caused by the bending of the PHS, to downdip compression beneath the Kii Peninsula. The seismicity in the subduction zone likely relates to the balance of stress in the incoming and the subducting plate as well as to coupling between the subducting and overriding plates.
On pathways and residence time of saltwater plumes in the Arkona Sea
Authors: Lass H. U. , Mohrholz V. , Seifert T.
Published: November 2005

Time series measurements of temperature, salinity, and current at the sills of the Arkona Basin have been performed during the winter seasons 1998/1999 and 1999/2000 together with ship‐based measurements of stratification and currents covering the whole Arkona Basin. Observations were supported by model simulations of saltwater inflow into the Arkona Basin. The pathway of the saltwater plume passing the Drogden Sill stretches southward along the western rim of the Arkona Basin and turns into the deeper parts of the basin through a trench at the northern rim of Kriegers Flak discharging at the eastern tip of Kriegers Flak into the saltwater pool in the center of the Arkona Basin. The saltwater plume branches into a western filament, which passes the gap between Mön Island and Kriegers Flak if its mass flux exceeds the transport capacity of the trench. The western filament drops down to the bottom of the SW Arkona Basin, which causes mixing and eddy shedding. The salt water passing the Darss Sill flows onto a wedge‐shaped submarine terrace stretching from the Darss Sill to Kap Arkona. This plume joins near Kap Arkona by dropping into the underlying western Drogden Sill plume associated with mixing and eddy shedding. The central saltwater pool of the Arkona Basin discharges geostrophically controlled through the Bornholm Gatt into the Bornholm Basin. An upper bound of the discharge time of the saltwater pool based on repeated temperature‐salinity diagrams was estimated to be 3 months, while the residence time estimated by an analytical model was 1 month. Mixing of the saltwater pool with the overlying brackish surface water was observed.
A general dispersion relation for internal gravity waves in the atmosphere or ocean, including baroclinicity, vorticity, and rate of strain
Authors: Jones R. Michael
Published: November 2005

The dispersion relation for internal gravity waves in the atmosphere or ocean is generalized to include all components of baroclinicity, vorticity, and rate of strain. This generalization is expressed in a coordinate‐free formulation suitable to be used as the Hamiltonian in a general ray tracing program. Comparison with other work in special cases is included.
Numerical evidence for thermohaline circulation reversals during the Maastrichtian
Authors: Pucéat Emmanuelle , Donnadieu Yannick , Ramstein Gilles , Fluteau Frédéric , Guillocheau François
Published: November 2005

The sensitivity of the Maastrichtian thermohaline circulation to the opening/closing of marine communications between the Arctic and North Pacific oceans is investigated through a set of numerical experiments using the model CLIMBER‐2 (Earth Model of Intermediate Complexity). We show here that the opening or closing of an Arctic‐Pacific marine gateway induces transitions between different equilibrium states of the thermohaline circulation. Sensitivity tests of the inferred modes of thermohaline circulation to atmospheric CO2 level changes have also been explored. An abrupt switch in deep convection from high northern to high southern latitudes, a change consistent with isotopic evidences, is reproduced by our simulations. The switch is caused by a combination of increased atmospheric CO2 concentration and inflow in the North Pacific of low‐salinity Arctic waters when the Arctic‐Pacific marine gateway is opened. The state of the gateway (open/closed) may have changed rapidly through variations in sea level that have been inferred for the Maastrichtian period.
A geomagnetic paleointensity stack between 0.8 and 3.0 Ma from equatorial Pacific sediment cores
Authors: Yamazaki Toshitsugu , Oda Hirokuni
Published: November 2005

We have conducted a paleomagnetic study of six sediment cores taken from the equatorial Pacific, three from the West Caroline Basin and three from the Manihiki Plateau, in order to make a relative paleointensity stack during the Matuyama and late Gauss Chrons. The age of the bottom of the cores ranges from 1.2 to 3.0 Ma. The sediments show little downcore changes in the proxies of magnetic grain size and mineralogy and are hence suitable for estimating relative paleointensity. The age of the cores is controlled by correlating variations in magnetic concentration (magnetic susceptibility and/or anhysteretic remanent magnetization (ARM)) to target oxygen‐isotope (δ18O) curves. All cores from the Manihiki Plateau show an upward decrease of the natural remanent magnetization (NRM) intensity normalized by ARM and isothermal remanent magnetization (IRM) with a decrease in sedimentation rate. Such a trend was removed before being converted to relative paleointensity. This observation implies that a sedimentation‐rate change can affect relative paleointensity estimation. Relative paleointensity records from the six cores coincide well with each other within uncertainty of age. We constructed a stacked curve between 0.8 and 3.0 Ma (the equatorial Pacific paleointensity stack EPAPIS‐3Ma) after adjusting age; the number of cores stacked is three to four throughout the record. Quasiperiodic paleointensity lows occur in the EPAPIS‐3Ma, and corresponding paleointensity lows can be found in previously published records with some shifts in age. At least, parts of the paleointensity minima seem to be accompanied by geomagnetic excursions. The “asymmetric sawtooth pattern” of paleointensity variations is not observed at the Matuyama‐Gauss boundary and thereafter in our record. A spectral analysis shows that ∼100 kyr orbital eccentricity frequency may exist in paleointensity variations during the Matuyama and late Gauss Chrons.
Evidence for a variable paleomagnetic lock‐in depth in the Holocene sequence from the Salerno Gulf (Italy): Implications for “high‐resolution” paleomagnetic dating
Authors: Sagnotti Leonardo , Budillon Francesca , Dinarès‐Turell Jaume , Iorio Marina , Macrì Patrizia
Published: November 2005

We report on a paleomagnetic and rock magnetic study of two adjacent marine gravity cores from the Salerno Gulf (Italy), with measurements carried out on u‐channel samples at 1‐cm spacing. The cores recover a sedimentary sequence spanning, in the overlapping part, the last ∼6000 years and include a thick (∼1 m) pumice layer produced during the Somma‐Vesuvius eruption of 79 A.D. Rock magnetic and lithostratigraphic data provide several tie‐points for a detailed correlation between the two cores. Paleomagnetic data allow the determination of a well‐defined characteristic remanent magnetization, with very similar stratigraphic trends and distinct features that can also be unambiguously correlated between the cores. However, the comparison of the various data sets points out that the paleomagnetic lock‐in depth in the two adjacent cores varies through the stratigraphic succession. We discuss the implication of such results for assessing the potential of high‐resolution paleomagnetic studies in dating sedimentary sequences on the basis of paleosecular variation of the geomagnetic field. In the studied case, the relative difference in the lock‐in depth in the two cores causes “spreading” of the assigned paleomagnetic ages at a century scale.
Further constraints on the deep lunar interior
Authors: Khan A. , Mosegaard K.
Published: November 2005

We have inverted the most recent set of geophysical observations pertinent to lunar interior properties, including mass M and moment of inertia I as determined by Lunar Prospector, the two Love numbers k2 and h2 as well as monthly tidal dissipation Q obtained from more than 35 years of lunar laser ranging data. In wanting to assess the ability of these parameters to constrain lunar mantle and core structure, we have used a stochastically based sampling algorithm to invert the geophysical data to obtain radial density and shear wave velocity profiles. The results indicate a small liquid Fe core (r < 400 km), with a shear wave velocity close to 0 km/s and a density of around 7 g/cm3. This is further corroborated by calculating the Bayes factor for the hypothesis that the lunar core is fluid against the hypothesis that it is solid, which is >1, thereby favouring the fluid core hypothesis. In addition, shear wave velocities for the lower mantle region (depths > 1100 km) are generally found to be lower than upper mantle velocities and can be interpreted as implying the presence of partial melt, which can explain the unusually low lunar monthly tidal Q of ∼30.
The transmitter pointing determination in the Geoscience Laser Altimeter System
Authors: Sirota J. Marcos , Bae Sungkoo , Millar Pamela , Mostofi David , Webb Charles , Schutz Bob , Luthcke Scott
Published: November 2005

The determination of accurate elevation data using laser altimetry relies on accurate knowledge of the instrument pointing angle. The Geoscience Laser Altimeter System (GLAS) on the Ice, Cloud and land Elevation Satellite (ICESat) uses a novel system for determination of the laser pointing vector. In this paper we describe this system, as well as the method used to process its data, which are required to meet ICESat's science objectives. We discuss the necessary modifications to processing techniques, implemented to optimize accuracy for the various operating conditions. Results to date are compared to calibration/validation data to assess their accuracy. We show that the stated requirements have been met for near nominal operating conditions.
Evidence for altitude‐dependent photolysis‐induced 18O isotopic fractionation in stratospheric ozone
Authors: Haverd Vanessa , Toon Geoffrey C. , Griffith David W. T.
Published: November 2005

We present vertical profiles of 18O fractionations in ozone, measured by balloon‐borne infrared remote sensing between 15 and 40 km. The magnitudes of the 16O16O18O (668O3) and 16O18O16O (686O3) fractionations are 13.5 ± 2.7% and 7.7 ± 2.2%, averaged over the 20–35 km altitude range, in good agreement with previous atmospheric measurements by mass spectrometry and both infrared and far infrared remote sensing spectroscopy. We use our fractionation profiles, together with known fractionation effects of the ozone formation reaction, to deduce fractionations attributable to photolysis. These photolytic fractionation profiles show significant increases with altitude (3.5 ± 2.2% and 4.0 ± 1.6% for 668O3 and 686O3 respectively over the 20–35 km altitude range), indicating that the ozone formation reaction alone does not account for the observed enrichments.
Dynamical amplification of polar warming
Authors: Cai Ming
Published: November 2005

This paper presents theoretical and modeling evidence suggesting that the atmospheric poleward heat transport can lead to a polar warming amplification (i) by redistributing part of the extra energy intercepted by the low‐latitude atmosphere to high latitudes, and (ii) by strengthening the water vapor feedback in high latitudes. For an anthropogenic radiative forcing of 4 Wm−2, we illustrate that the dynamical amplifier contributes to about 1/4 (1/10) of the total high‐latitude (global) surface warming in winter in a simple coupled atmosphere‐surface moist radiative‐transportive climate model. Budget analysis of the radiation fluxes at the top of the atmosphere derived from IPCC AR4 CGCM climate simulations seems to support the dynamical amplifier theory for the larger warming in high latitudes.
On large outflows of Arctic sea ice into the Barents Sea
Authors: Kwok Ron , Maslowski Wieslaw , Laxon Seymour W.
Published: November 2005

Winter outflows of Arctic sea ice into the Barents Sea are estimated using a 10‐year record of satellite ice motion and thickness. The mean winter volume export through the Svalbard/Franz Josef Land passage is 40 km3, and ranges from −280 km3 to 340 km3. A large outflow in 2003 is preconditioned by an unusually high concentration of thick perennial ice over the Nansen Basin at the end of the 2002 summer. With a deep atmospheric low situated over the eastern Barents Sea in winter, the result is an increased export of Arctic ice. The Oct‐Mar ice area flux, at 110 × 103 km2, is not only unusual in magnitude but also remarkable in that >70% of the area is multiyear ice; the ice volume flux at ∼340 km3 is almost one‐fifth of the ice flux through the Fram Strait. Another large outflow of Arctic sea ice through this passage, comparable to that in 2003, is found in 1996. This southward flux of sea ice represents one of two major sources of freshwater in the Barents Sea; the other is the eastward flux of water via the Norwegian Coastal Current. The possible consequences of variable freshwater input on the Barents Sea hydrography and its impact on transformation of Atlantic Water en route to the Arctic Ocean are examined with a 25‐year coupled ice‐ocean model.
On the correlation of seismic microtremors
Authors: Chávez‐García Francisco J. , Luzón Francisco
Published: November 2005

We present results of the analysis of microtremor measurements using a small array. Our analysis is based on the computation of cross‐correlation functions between stations in both frequency and time domains. We obtain similar results in both domains and link those results to the application of Aki's spatial autocorrelation method of using a single station pair and to recent studies that have shown that the Green's function between two stations can be retrieved from the temporal cross correlation of seismic noise. We show that the same simple subsoil structure allows interpretation of our correlation results in time and frequency. We observe both Love and Rayleigh waves; however, Love waves dominate the records in our lower‐frequency range (between 3.6 and 6 Hz), while Rayleigh waves are prevalent in the records in our higher‐frequency band (from 6 to 20 Hz). Frequency domain cross correlation yields better results in the lower‐frequency range, while time domain cross correlation shows very clear results in the higher‐frequency band. Thus both analyses are complementary. Our results show that ambient vibration recorded at the free surface includes different types of waves but that the correlation between any two stations is governed by the more stable propagation mode between them, surface waves in the case of a layered medium. Our results shed some light on the nature of microtremors and on the reasons why the spatial autocorrelation method or the horizontal‐to‐vertical spectral ratios are useful in geophysical and site response studies.
Earthquake nucleation on (aging) rate and state faults
Authors: Rubin A. M. , Ampuero J.‐P.
Published: November 2005

We obtain quasi‐static, two‐dimensional solutions for earthquake nucleation on faults obeying Dieterich's “aging” version of the rate and state friction equations. Two distinct nucleation regimes are found, separated by roughly a/b ∼ 0.5, where a and b are the constitutive parameters relating changes in slip rate V and state θ to frictional strength. When fault healing is unimportant (Vθ/Dc ≫ 1, where Dc is the characteristic slip distance for the evolution of θ), the nucleation zone spontaneously evolves toward a state of accelerating slip on a patch of fixed half length Lν ≈ 1.3774(μ′Dc/bσ), where μ′ is the intrinsic stiffness of the medium and σ is the normal stress. This is the fixed length solution for which the stress intensity factor K = 0. Although this solution does not depend upon a/b explicitly, only for a/b < 0.3781 does healing remain unimportant as instability is approached. For a/b ≳ 0.5 and a wide range of slow loading conditions, Vθ/Dc ultimately approaches a quasi‐constant value near 1, and the nucleation zone takes on the appearance of an expanding slip‐weakening crack. A fracture energy balance indicates that in this regime the nucleation length asymptotically approaches π−1[b/(b − a)]2(μ′Dc/bσ), a result that is consistent with the numerical simulations despite considerable complexity asa approaches b. This suggests that nucleation lengths can sometimes be much larger than those found by Dieterich (e.g., by a factor of 100 for a/b = 0.95). For surfaces this close to velocity neutral, nucleation might produce signals detectable by surface seismometers for values of Dc at the upper end of the lab range (100 μm). However, the attributes of the aging law that give rise to such large nucleation lengths may be nonphysical; additional laboratory experiments are needed to address this issue.