bluuebunny/crossref_metadata_2025 huggingface dataset:
Are There Alfvén Waves in the Solar Atmosphere?
Authors: Erdélyi R. , Fedun V.
Published: December 2007

The Sun's outer coronal layer exists at a temperature of millions of kelvins, much hotter than the solar surface we observe. How this high temperature is maintained and what energy sources are involved continue to puzzle and fascinate solar researchers. Recently, the Hinode spacecraft was launched to observeand measure the plasma properties of the Sun's outer layers. The data collected by Hinode reveal much about the role of magnetic field interactions and how plasma waves might transport energy to the corona. These results open a new era in high-resolution observation of the Sun.
Gardnerella vaginalisBacteremia in a Previously Healthy Man: Case Report and Characterization of the Isolate
Authors: Lagacé-Wiens Philippe R. S. , Ng Betty , Reimer Aleisha , Burdz Tamara , Wiebe Deborah , Bernard Kathryn
Published: December 2007

Gardnerella vaginalisin women causes vaginitis or infections in other sites, such as the urinary tract, but is an infrequent cause of bacteremia. Bacteremia in men is very rare and is typically associated with immunocompromised states. Here we describeG. vaginalisbacteremia in a previously healthy man with renal calculi and urosepsis.
Melon Chlorotic Leaf Curl Virus
: Characterization and Differential Reassortment with Closest Relatives Reveal Adaptive Virulence in the
Squash Leaf Curl Virus
Clade and Host Shifting by the Host-Restricted
Bean Calico Mosaic Virus
Authors: Idris A. M. , Mills-Lujan K. , Martin K. , Brown J. K.
Published: December 2007

The genome components of the
Melon chlorotic leaf curl virus
(MCLCuV) were cloned from symptomatic cantaloupe leaves collected in Guatemala during 2002. The MCLCuV DNA-A and DNA-B components shared their closest nucleotide identities among begomoviruses, at ∼90 and 81%, respectively, with a papaya isolate of MCLCuV from Costa Rica. The closest relatives at the species level were other members of the
Squash leaf curl virus
(SLCV) clade, which is endemic in the southwestern United States and Mexico. Biolistic inoculation of cantaloupe seedlings with the MCLCuV DNA-A and -B components resulted in the development of characteristic disease symptoms, providing definitive evidence of causality. MCLCuV experimentally infected species within the
Cucurbitaceae, Fabaceae
, and
Solanaceae
. The potential for interspecific reassortment was examined for MCLCuV and its closest relatives, including the bean-restricted
Bean calico mosaic virus
(BCaMV), and three other cucurbit-infecting species,
Cucurbit leaf crumple virus
(CuLCrV), SLCV, and SMLCV. The cucurbit viruses have distinct but overlapping host ranges. All possible reassortants were established using heterologous combinations of the DNA-A or DNA-B components. Surprisingly, only certain reassortants arising from MCLCuV and BCaMV, or MCLCuV and CuLCrV, were viable in bean, even though it is a host of all of the “wild-type” (parent) viruses. The bean-restricted BCaMV was differentially assisted in systemically infecting the cucurbit test species by the components of the four cucurbit-adapted begomoviruses. In certain heterologous combinations, the BCaMV DNA-A or -B component was able to infect one or more cucurbit species. Generally, the reassortants were less virulent in the test hosts than the respective wild-type (parent) viruses, strongly implicating adaptive modulation of virulence. This is the first illustration of reassortment resulting in the host range expansion of a host-restricted begomovirus.
Three-Dimensional Structure Determines the Pattern of CD4+T-Cell Epitope Dominance in Influenza Virus Hemagglutinin
Authors: Landry Samuel J.
Published: December 2007

The structural context of a CD4+T-cell epitope is known to influence immunodominance at the level of antigen processing, but general rules have not emerged. Dominant epitopes of influenza virus hemagglutinin are found to be localized to the C-terminal flanks of conformationally stable segments identified by low crystallographic B-factors or high COREX residue stabilities. The bias toward C-terminal flanks is distinctive for antigens from the influenza virus. Dominant epitopes in antigens/allergens from other sources also localize to the flanks of stable segments but are found on either N- or C-terminal flanks. Thus, dominance arises from preferential endoproteolytic nicking between stable segments followed by loading of fragment terminal regions into antigen-presenting proteins. This mechanism probably arose in order to direct CD4+responses onto sequences that are conserved for structure and function. Structure-guided presentation could enhance protection against genetically drifting influenza virus variants but most likely reduces protection against new viral subtypes.
Maternal depression, child behavior, and injury
Authors: Phelan K , Khoury J , Atherton H , Kahn R S
Published: December 2007

Background:

Few data exist on the effect of maternal depression on child injury outcomes and mediators of this relationship.

Objective:

To examine the relationship between mothers’ depressive symptoms and medically attended injuries in their children and the potential mediating role of child behavior.

Design/Methods:

A cohort of mother–child dyads from the National Longitudinal Study of Youth followed from 1992 to1994. The primary exposure variable was maternal depressive symptoms as measured by the Center for Epidemiologic Studies Depression Scale in 1992. Child behavior was assessed by the Behavior Problems Index externalizing subscale. Logistic regression was used to examine the relationship between depressive symptoms, child behavior, and injury reported in the prior year in 1994.

Results:

94 medically attended injuries were reported in the 1106 children (8.5%); two-thirds were sustained in the home environment. Maternal depressive symptoms significantly increased the risk of child injury; injury risk increased 4% for every 1-point increase in depressive symptoms (adjusted OR 1.04, 95% CI 1.01 to 1.08, p = 0.02). Increasing maternal depressive symptoms also increased the risk of externalizing behavior problems (adjusted OR 1.06, 95% CI 1.03 to 1.09), but externalizing behavior problems did not significantly mediate the relationship between maternal symptoms and child injury.

Conclusions:

Increasing depressive symptoms in mothers was associated with an increased risk of child injury. Child behavior did not significantly mediate the association between maternal depressive symptoms and child injury in this cohort. Greater recognition, referral, and treatment of depressive symptoms in mothers may have effects on child behavior and injury risk.
Neisseria gonorrhoeaemulti-antigen sequence typing (NG-MAST) of ciprofloxacin resistant isolates of Pretoria, South Africa
Authors: De Jongh M , Dangor Y , Ison C A , Hoosen A A
Published: December 2007

Gonococcal isolates resistant to ciprofloxacin collected from 2004 to 2005, in the Pretoria region, were characterised usingNeisseria gonorrhoeaemulti-antigen sequence typing (NG-MAST). The isolates were obtained from men presenting with urethritis to primary healthcare clinics and general practitioners. All isolates were tested for susceptibility to ciprofloxacin by Etest, disc diffusion and agar dilution methods. Sequence-based typing, directed at theporandtbpBgenes, and compared with international isolates using the NG-MAST database on the internet, was done for 18 isolates (10 ciprofloxacin-resistant isolates and 8 susceptible controls). There was one cluster (four isolates) of known sequence type (ST) similar to the pattern seen among strains from Scotland, England, and Durban, South Africa. Two other known STs were identified, while the remaining STs were unique.
Detection of plasmid-mediated AmpC inEscherichia coli,Klebsiella pneumoniaeandProteus mirabilis: Table 1
Authors: Tan T Y , Ng S Y , Teo L , Koh Y , Teok C H
Published: December 2007

Aims:

This study investigated the prevalence of plasmid-mediated AmpC production in selected clinical isolates ofEscherichia coli,Klebsiellaspecies andProteus mirabilis, and compared the results of boronic acid disc screening with conventional susceptibility testing for the detection of AmpC-positive isolates.

Methods:

E coli,Klebsiellaspecies andP mirabiliswith reduced susceptibility to amoxycillin-clavulanate, cefuroxime and cephalexin, but without phenotypic evidence of extended-spectrum β-lactamases were screened for AmpC activity using enzyme-extraction methods. The presence of plasmid-mediatedampCwas determined by multiplex PCR. Antibiotic susceptibilities were determined using both disc and dilution-based methods. A disc-based screening method for detection of AmpC-producing strains was evaluated using boronic acid as an inhibitor of AmpC, and cefoxitin as the antibiotic substrate.

Results:

Plasmid-mediatedampCwas present in 26% of study isolates, with CMY-like enzymes detected predominantly inE coliand DHA-like enzymes predominantly inKlebsiella pneumoniae. Current susceptibility methods failed to detect a significant proportion of plasmid-mediated AmpC-producing isolates, with 33% of such strains interpreted as susceptible to third-generation cephalosporins using current Clinical Laboratory Standards Institute breakpoints. The boronic acid disc method showed sensitivity and specificity of 90% and 98% respectively in detecting AmpC-positive isolates.

Conclusion:

The prevalence of plasmid-mediatedampCwas high in the study population, and may be missed by conventional susceptibility testing methods. Inhibitor-based screening methods would improve detection of this emerging resistance phenotype.
PHYSICS OF RANDOMNESS AND REGULARITIES FOR CITIES, LANGUAGES, AND THEIR LIFETIMES AND FAMILY TREES
Authors: TUNCAY Ç
Published: December 2007

Time evolution of the cities and languages is considered in terms of multiplicative noise1and fragmentation2processes; where power law (Pareto-Zipf law)3and slightly asymmetric log-normal (Gauss)4distribution result for the size distribution of the cities and for that of the languages, respectively. The cities and the languages are treated differently (and as connected; for example, the languages split in terms of splitting the cities, etc.) and thus two distributions are obtained in the same computation at the same time. Evolutions of lifetimes and families for the cities and the languages are also studied. We suggest that the regularities may be evolving out of randomness, in terms of the relevant processes.
AGGREGATE DYNAMICS IN AN EVOLUTIONARY NETWORK MODEL
Authors: SEUFERT ADRIAN M. , SCHWEITZER FRANK
Published: December 2007

We analyze a model of interacting agents (e.g. prebiotic chemical species) which are represented by nodes of a network, whereas their interactions are mapped onto directed links between these nodes. On a fast time scale, each agent follows an eigendynamics based on catalytic support from other nodes, whereas on a much slower time scale the network evolves through selection and mutation of its nodes-agent. In the first part of the paper, we explain the dynamics of the model by means of characteristic snapshots of the network evolution and confirm earlier findings on crashes and recoveries in the network structure. In the second part, we focus on the aggregate behavior of the network dynamics. We show that the disruptions in the network structure are smoothed out, so that the average evolution can be described by a growth regime followed by a saturation regime, without an initial random regime. For the saturation regime, we obtain a logarithmic scaling between the average connectivity per node 〈l〉s and a parameter m, describing the average incoming connectivity, which is independent of the system size N.
THE METHODS FOR MEASURING SHEAR STRESS OF POLAR MOLECULE DOMINATED ER FLUIDS
Authors: SHEN RONG , WANG XUEZHAO , LU YANG , SUN GANG , WEN WEIJIA , LU KUNQUAN
Published: December 2007

A series of ER fluids materials with high shear stress have been developed recently, which named as polar molecule dominated electrorheological (PM-ER) fluids. Difficulties have been met in shear stress measurement process due to the slide of PM-ER fluids on the surface of metallic electrodes. In this paper, two shearing configurations have been developed to remove the interface effect. The intrinsic shear stress of ER fluids can be obtained by using the devices.
DYNAMIC BEHAVIOR AND YIELDING OF FIELD-RESPONSIVE PARTICULATE SUSPENSIONS
Authors: SEE HOWARD , JOUNG CLINTON , EKWEBELAM CHARLES
Published: December 2007

We have examined the small strain response of an inverse ferrofluid system, consisting of micron-sized inert particles dispersed in a ferrofluid, which is a magnetisable liquid consisting of single domain magnetite nanoparticles. Under a magnetic field the inert particles will form elongated aggregates in the field direction, analogous to a magnetorheological fluid. It was found that the fluid appeared to have a Bingham fluid-like yield stress when analysed using the flow curve. However careful study of the behavior at very low shear rates revealed an ever decreasing shear stress. In addition, the behavior of conventional magnetorheological fluids at large strains under steady shear flow and constant magnetic field was also studied, and the results compared to particle-level computer simulations.
SELF-ASSEMBLY MORPHOLOGIES AND ELECTRORHEOLOGICAL PROPERTIES OF POLYANILINE-POLY(ETHYLENE GLYCOL)- POLYANILINE TRIBLOCK COPOLYMERS
Authors: MA HUI-RU , GUAN JIAN-GUO , YUAN RUN-ZHANG
Published: December 2007

The self-assembly properties and ER effects of the Polyaniline-Poly(ethylene glycol)-Polyaniline (PAn-PEG-PAn) triblock copolymers were studied in this paper. The results indicate that with the increase of solubility parameter of the solvent, PAn-PEG-PAn copolymers form into different morphologies of spheriods, vesicles and rods. PAn-PEG-PAn copolymers with vesicles morphology show the highest polarization strength, while those with rods have the most rapid polarization rate. Among the PAn-PEG-PAn copolymers of different morphologies, the PAn-PEG-PAn copolymer vesicles show the strongest ER effect.
COLE-COLE ANALYSIS ON DIELECTRIC SPECTRA OF ELECTRORHEOLOGICAL SUSPENSIONS
Authors: CHOI H. J. , HONG C. H. , JHON M. S.
Published: December 2007

Along with rheological properties, dielectric spectra of the ER fluids were found to provide additional information on both analyzing their electrical polarization properties and interpreting their flow behavior. Dielectric properties of three different material systems such as spherical-monodisperse polymer microspheres (PAPMMA) consisting of a poly(methyl methacrylate) (PMMA) core and a polyaniline (PANI) shell, single-doped and mesoporous-doped TiO 2 system and copper phthalocyanine-doped mesoporous TiO 2 suspensions based ER fluid were analyzed via dielectric spectra of permittivity and loss factor as a function of the frequency, and Cole-Cole plots. Polarizability which is defined as a difference of dielectric constant at both zero frequency and infinite frequency was found to be a proper parameter to understand a better ER fluid. Using the Cole-Cole plot, we were not only able to fit the dielectric spectra, but also to deduce the achievable polarizability by explaining the higher ER performance of the ER fluids.
PREPARATION AND ELECTRORHEOLOGICAL CHARACTERISTICS OF PANI/MWNT NANOCOMPOSITE
Authors: LIM J. Y. , KIM S. T. , PARK B. J. , CHOI H. J.
Published: December 2007

We prepared polyaniline (PANI) /multi-walled carbon nanotube (MWNT) nanocomposites of both PANI pierced MWNT nanocomposites synthesized using polyvinyl alcohol) as a polymeric stabilizer and PANI/MWNT nanocables via an in-situ oxidative polymerization directed by a cationic surfactant of cetyltrimethylammonium bromide (CTAB). In addition to chemical analysis of the products, the formation of nanocomposite nanocable and their morphology in which the MWNTs were entirely encapsulated by amorphous PANI, were confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Electrorheological (ER) fluids were prepared by dispersing both of these synthesized MWNT/PANI nanocomposites in insulating silicone oil and their ER properties were investigated by controlling applied DC electric field strengths. The synthesized nanocomposite particles have enhanced interparticle interactions, and the shear stresses increase with the electric field strength for a broad range of shear rate. Among three different constitutive equations adopted, the Cho-Choi-Jhon model was found to fit the flow curves quite well.
MANUFACTURE OF BULK MAGNETORHEOLOGICAL ELASTOMERS USING VACUUM ASSISTED RESIN TRANSFER MOLDING
Authors: WOODS B. K. S. , WERELEY N. , HOFFMASTER R. , NERSESSIAN N.
Published: December 2007

Magnetorheological elastomers (MREs) consist of ferromagnetic particles embedded in a compliant matrix (i.e. elastomer). Due to the magnetic interaction of the ferromagnetic particles, MREs exhibit field dependent physical properties. Very significant changes in the modulus and loss factor of the elastomer can be realized. This makes MREs a promising candidate for active vibration control mechanisms. One factor currently limiting the implementation of this technology is the lack of an efficient manufacturing method that is practical for mass production. Most of the specimens created for previous MRE research were made using simple casting or mechanical mixing methods that are not ideal. In this research a new methodology for producing MREs using Vacuum Assisted Resin Transfer Molding (VARTM) was investigated. The method was used with a range of iron particles sizes and silicon elastomer systems and found to be effective within certain limits of applicability. The specimens produced were tested in compression under a range of magnetic fields to validate the presence of the MR effect. Relative changes in compressive modulus ranging from 35% to 150% (depending on volume fraction), under fields of around 0.3T were observed.
BIANCHI TYPE I COSMOLOGIES WITH THE DARK MATTER IN THE BACKGROUND OF DARK ENERGY
Authors: BANDYOPADHYAY TANWI , CHAKRABORTY NARAYAN CHANDRA , CHAKRABORTY SUBENOY
Published: December 2007

This paper deals with the cosmological study of the Bianchi type I model made of dust fluid in the background of dark energy. Cosmological solutions are obtained for the following four cases: (i) only with dark matter; (ii) only with dark energy; (iii) both dark matter and dark energy are present but without interaction; (iv) interactive dark matter and dark energy.
CONSTRAINTS ON SIMPLIFIED QUARTESSENCE COSMOLOGY FROM THE LATEST OBSERVATIONAL DATA
Authors: WU PUXUN , DONG SUMEI
Published: December 2007

The simplified generalized Chaplygin gas (GCG) model as a candidate of UDME is studied in this paper. By using the latest 162 ESSENCE type Ia supernovae (Sne Ia ) data, 30 high red shift Sne Ia data and the distance ratio from z = 0.35 to z = 1089 (the red shift of decoupling), we obtain [Formula: see text] and [Formula: see text] at a 95.4% confidence level. In addition the deceleration parameter for this simplified GCG model is investigated, and we find that the universe, at a 1σ confidence level, enters the acceleration era at the red shift zq = 0~ 0.53 - 0.66 and possesses an acceleration -qz = 0~ 0.66 - 0.78 at present.
ANALYTICAL MODELS FOR QUARK STARS
Authors: KOMATHIRAJ K. , MAHARAJ S. D.
Published: December 2007

We find two new classes of exact solutions to the Einstein–Maxwell system of equations. The matter content satisfies a linear equation of state consistent with quark matter; a particular form of one of the gravitational potentials is specified to generate solutions. The exact solutions can be written in terms of elementary functions, and these can be related to quark matter in the presence of an electromagnetic field. The first class of solutions generalizes the Mak–Harko model. The second class of solutions does not admit any singularities in the matter and gravitational potentials at the center.
SUPPORTING DISTRIBUTED EVENT-CONDITION-ACTION RULES IN A MULTIDATABASE ENVIRONMENT
Authors: KANTERE VERENA , KIRINGA ILUJU , MYLOPOULOS JOHN
Published: December 2007

We describe a mechanism based on distributed Event-Condition-Action (ECA) rules that supports data coordination in a multidatabase setting. The proposed mechanism includes an ECA rule language and a rule execution engine that transforms rules when they are first posted, and then coordinates their execution. Like traditional ECA rules, our ECA rule language has three parts: an event language, a condition language, and an action language. The event language provides a set of operators with a formal semantics for a multidatabase environment, and which allows a wide variety of composite events. The condition language provides Boolean algebra operators that take as operands either composite or simple conditions. The action language provides a conjunction of simple or composite actions. The execution model partitions rules to more easily manageable forms, distributes them to relevant databases, monitors their execution and composes their evaluations. The mechanism has been designed in a manner that minimizes the number of messages that need to be exchanged over the network. We have also conducted an experimental evaluation to compare the implementation with a naïve centralized execution model. The paper also presents a prototype implementation as well as experimental results on its performance. This work is part of an on-going project intended to develop data coordination techniques for data sharing settings.
Friction melting, catastrophic dilation and breccia formation along caldera superfaults
Authors: Kokelaar Peter
Published: December 2007

At Glencoe caldera volcano, friction melts and magmas transformed explosively to froth or spray where they encountered rapid decompression in dilatant sections of superfaults. The friction melts were blasted upwards, plastering free surfaces, and were rapidly followed by fragmented magma and then liquid magma that formed intrusions. Irregular contacts of fault intrusions record explosive disruption of hydrothermal systems cut by the dilational faults, with lithic breccias removed from the rapidly formed cavities before the arrival of melt spray. Layers of lithic breccia are common in ignimbrites around calderas and usually show incorporation of hot and hydrothermally altered rocks. Such layers may specifically reflect initial superfault dilation during caldera collapse.
Geological and biological evidence for regional drainage reversal during lateral tectonic transport, Marlborough, New Zealand
Authors: CRAW D. , WATERS J.
Published: December 2007

A 2500 km
2
mountainous river catchment in northern South Island, New Zealand, drained southwards until the late Quaternary. The catchment is being transported laterally at
c
. 36 mm a
−1
relative to the southern South Island by dextral strike-slip motion along the Pacific–Australian Plate boundary (Alpine Fault). This lateral motion has moved the eastern half of the catchment from a zone of uplift into a zone of subsidence over the past million years, triggering drainage reversal. Sedimentation from the catchment switched from a sedimentary basin in the SE to a basin in the north. Profiles of river terrace remnants, formed from glacial outwash, show that drainage reversal occurred in the latter stages of deposition of the oldest recognizable terrace. Clast imbrication patterns and clast petrography in that terrace indicate southward flow, whereas flow had a northerly component in younger terraces and a nearby active river. In addition, 1.6% genetic divergence of fish on either side of the new drainage divide is consistent with late Quaternary separation by drainage reversal. The timing of drainage reversal is estimated from regional terrace correlation and the magnitude of the genetic divergence to be between 100 and 200 ka bp.
Tectonic and metamorphic evolution of the Temsamane units, External Rif (northern Morocco): implications for the evolution of the Rif and the Betic–Rif arc
Authors: Negro F. , Agard P. , Goffé B. , Saddiqi O.
Published: December 2007

Located at an intermediate position in the External Rif nappe pile, the Temsamane units (northern Morocco) are characterized by an abnormally intense metamorphism and a penetrative ductile deformation. We present new metamorphic data showing that, in spite of their external position in the Rif, part of the Temsamane units underwent medium-pressure low-temperature (MP–LT) metamorphism (at
c
. 7–9 kbar and 330–430 °C), possibly during the Oligocene. Structural data show that the exhumation of these units, during Middle to Late Miocene times, was characterized by an intense approximately east–west stretching and by top-to-the-west shear senses. We tentatively propose two possible origins for the MP–LT Temsamane units: (1) an internal origin related to the subduction and the HP–LT event recorded in the Internal Rif (Alboran Domain), or (2) an external origin, implying a second subduction system within the External Rif, parallel to and almost contemporaneous with that of the Alboran Domain. This tectonometamorphic evolution of the Temsamane units is set within the context of the External Rif evolution. At a larger scale, we show that the exhumation history of the Temsamane units, which strongly resembles that documented in the core of the internal Betics, is compatible with the westward slab retreat occurring during the Middle to Late Miocene in the Betic–Rif region.
Kirmenjak-
Pietra d'Istria
: a preliminary investigation of its use in Venetian architectural heritage
Authors: Šimunić Buršić M. , Aljinović D. , Cancelliere S.
Published: December 2007

Kirmenjak — white limestone from the quarries near the village of Kirmenjak in Istria (Croatia), in the past known as
Pietra d'Istria
— has been regularly used in the construction of the basal zone of Venetian buildings since the 14th century. Its characteristics — durability, extremely low water absorption and high compressive strength — made it an ideal material for the lowest parts of Venetian buildings in the zone between foundation (wooden piles) and brick walls. In this zone, exposed to tidal flooding and low-tide drying, materials deteriorate very quickly, but Kirmenjak has proved to be durable even in this aggressive saline environment. Moreover, this dense micritic or pelmicritic stylolitized limestone from the Upper Jurassic (Tithonian) was used as an efficient barrier to rising damp. Preliminary
in situ
investigation of how Kirmenjak blocks were laid shows that the prevalent stylolite orientation is horizontal in the basal parts of buildings, while in other structural elements this orientation varies. This inspired the hypothesis that the Venetian constructors took advantage of horizontally laid stylolite discontinuities (partially filled with clay) as a multilayer humidity barrier.
An holistic approach to the assessment of stone decay: Bonamargy Friary, Northern Ireland
Authors: McCabe S. , Smith B. J. , Warke P. A.
Published: December 2007

Decay mapping and condition assessment have proved to be useful tools in understanding stone decay and identification of remedial action. In this paper an holistic strategy is taken to the study of façade decay at the medieval Bonamargy Friary, on the north Antrim coast, Northern Ireland. After lithology and decay forms are mapped, interrelationships between decay form, stone type and environment are identified and quantified. This is accomplished through analysis of the spatial association of decay forms, and is used to inform our understanding of decay processes and environmental and lithological controls on those processes. This approach is combined with the application of the UAS (‘Unit’, ‘Area’, ‘Spread’) staging system developed by Warke
et al.
that is based upon a ‘whole-building’ approach to the assessment of stone condition, the spread to decay and a staged approach to conservation intervention. The case study demonstrates how the combination of these approaches improves our understanding of the factors that control stone decay whilst providing a clearer understanding of the cumulative impact of combined decay mechanisms.
Exploring the nature of myth and its role in science
Authors: Masse W. Bruce , Barber Elizabeth Wayland , Piccardi Luigi , Barber Paul T.
Published: December 2007

The scientific study of myth is dominated by a paradigm that recognizes myth as having been viewed as truthful narrative history by past traditional cultures and yet is considered false or otherwise suspect by the modern scholars who study myth. Although virtually all scholars recognize that myth was of critical importance for traditional cultures, the attempt to elicit scientific reasons for this importance has led to many competing theories, few of which place an emphasis on the validity of myths as representing the product of actual observed historical natural events. This paradox may hinder our understanding of the origins of myth and prevent us from fully appreciating a critical aspect of why myth was so highly valued by past cultures. To set the stage for our examination of the possible natural history core of myth, we discuss briefly the history of the western scientific study of myth, with an emphasis on geological sciences. We then explore the cognitive structure of myth and provide working principles about how the historical information contained in these myths can be transmitted faithfully through successive generations and can be elicited by scientific study. Although recognizing the extreme complexity of myth as a cultural product, our data indicate that a science-based natural history approach can lead to important insights regarding the nature of myth.
Environment and natural hazards in Roman and Medieval texts: presentation of the CLEMENS database project
Authors: Vittori Eutizio , Fulloni Sabina , Piccardi Luigi
Published: December 2007

CLEMENS, acronym for
Corpus Latinorum Et Mediaevalium Naturae Scriptorum
, is a new electronic archive of
excerpta
reporting environment-related data contained in the literary and epigraphic sources of classical Roman and Medieval age. The aim is to fill a gap in information about environmental disruptions or memorabilia that occurred in ancient times within the Mediterranean basin, and to verify whether any useful information has eluded our knowledge. One of the main purposes of the systematic gathering and cataloguing carried out by CLEMENS is to become an extensive easy-to-search tool, offering the scientific community complete annotated documentation of what is available inside ancient sources about the natural environment in the Mediterranean. This information, currently dispersed in a variety of publications that may be difficult to access, has often proven essential for hazard assessment in several areas of the former Roman empire. It also contributes significantly to the understanding of changes caused by environmental events over the centuries, and of their incidence on natural habitats and on cultural heritage. The analysis of such interconnections may lead to a much improved understanding of either natural environment, hazards and cultural setting, as shown by interdisciplinary investigations merging together science, archaeology and history or even myth.

Considering the vast amount of documentation, the work is still far from completion. However, the encouraging preliminary results will soon be available on the web.
Geological histories and geohazard potential of Pacific Islands illuminated by myths
Authors: Nunn Patrick D. , Pastorizo Ronna
Published: December 2007

Understanding of the geological history of the Pacific, especially its geohazard potential, can be improved using details in ancient and properly-authenticated Pacific Islander myths. To demonstrate this, a synthesis of Pacific Island origin myths involving islands having been either ‘fished up’ or ‘thrown down’ is presented, with an account of origin myths for the island Niue used as a case study. A discussion of geohazards and myths in the Pacific focuses on tsunami, coseismic uplift, and island flank collapse, the last being illustrated by the first analysis of myths recalling ‘vanished islands’ in the Pacific.
Giants and elephants of Sicily
Authors: Agnesi V. , Di Patti C. , Truden B.
Published: December 2007

In Sicily, the great abundance of fascinating and impressive natural phenomena, have fed the imagination of men, who have interpreted them as the manifestation of the existence of supernatural and fantastic beings giving rise to myth and legend. Amongst these many myths, that of the cyclops Polyphemus, is closely linked to the geopalaeontological history of Sicily. The discovery, often inside caves, of the fossil skulls of elephants, in which there is a great nasal hollow (in the frontal part) where there was a trunk in life, gave rise to the belief that one-eyed giants had existed, in the past. The nasal hollow was wrongly interpreted as the orbit of a single frontal eye that characterized these monstrous beings, and the gigantic size was inferred by the notable dimensions of the skulls and the bones that are frequently found. In 1830 Giorgio Cuvier, attested to the fossil nature of the bones and put an end to the different inferences formulated about their origin.
Sand and mud flux estimates using acoustic and optical backscatter sensors: measurements seaward of the Wash, southern North Sea
Authors: Bass Sarah J. , McCave I. N. , Rees J. M. , Vincent C. E.
Published: December 2007

Optical and acoustic backscatter sensors, more sensitive to fine and sandy sediment respectively, were used to measure the mud and sand components of a mixed suspension at a site seaward of the Wash embayment, in the southern North Sea. Data were acquired from a free-standing instrument frame during a five-week deployment in 12 m water depth about 6 km offshore. Suspended mud at this site was characterized by tidal advection of fine sediment along the coast resulting in semi-diurnal peaks in concentration near slack water. Suspended sand concentrations correlated well with tidal current speeds indicating local resuspension behaviour. Predicted sand flux direction followed the residual current while mud fluxes at the site were different in direction to both the residual current and sand flux. Residual fluxes may be biased by cumulative errors resulting from instrument calibration and inferred vertical concentration profiles. These factors are assessed in relation to both predicted flux magnitudes and directions.
Modelling SPM on the NW European shelf seas
Authors: Souza Alejandro J. , Holt Jason T. , Proctor Roger
Published: December 2007

The Proudman Oceanographic Laboratory Coastal Ocean Modelling System (POLCOMS) has been developed to tackle multidisciplinary studies in coastal/shelf environments. The central core is a sophisticated three-dimensional hydrodynamic model that provides realistic flow fields to interact with, and transport environmental parameters. The model uses realistic forcing with ocean currents and hydrography at the boundary, atmospheric forcing and tides.

Suspended particulate matter (SPM) is transported within the water, like any other scalar in the model; it is advected using a high-order scheme and mixed vertically using diffusion coefficients from a second moment turbulence closure. In addition, the SPM transport is influenced by a number of processes unique to this problem, such as: the transfer between the lowest level of the model and the bed layer in which the resuspension and deposition takes place is dependent on the erosion rate, the particle settling velocity and the critical stresses for erosion and deposition. The particular application described in this paper is an annual simulation for the NW European shelf for a single sediment class.

The simulation shows the expected seasonal variation in spatial patterns and a clear tidal signal in the SPM resuspension. Also evident is a fortnightly/monthly variability due to the spring-neaps and the M2-N2 cycles. There are also quarter-diurnal and semi-diurnal cycles in SPM, due to tidal resuspension and advection respectively. The above tidal suspension behaviour, as well as, the net transport direction are in agreement with historical observations of SPM.
A late Atokan regional encrinite (early late Moscovian, Middle Pennsylvanian) in the Sierra Agua Verde, Sonora state, NW Mexico
Authors: Buitrón-Sánchez B. E. , Gómez-Espinosa C. , Almazán-Vázquez E. , Vachard D.
Published: December 2007

In the Sierra Agua Verde, central Sonora state, NW Mexico, the La Joya Formation exhibits an alternation (100 m thick) of calcareous siltstone and fossiliferous limestone with nodular cherts. This latter contains an abundant and diverse late Atokan (i.e. Podolskian = early late Moscovian, Middle Pennsylvanian) fossil assemblage composed of phylloid algae, fusulinids, chaetetids, tabulate corals, gastropods, fenestellid bryozoans, spiriferid and productid brachiopods, crinoids and conodonts. The crinoidal beds constitute a good example of a regional encrinite. They include several species of the parataxonomic stem form-genera
Cyclocaudex, Cyclocrista, Heterosteleschus, Mooreanteris, Pentagonopterix, Preptopremnum, Cycloscapus
and
Pentaridica
. Their preservation indicates the combination of preburial decay on the sea floor and post-burial decay within the sediment. The high degree of silicification of the crinoids indicates that they were possibly associated with siliceous organisms (Porifera?), not preserved in the assemblages. The studied thanatocoenosis is typical of tropical shallow seas, and reveals strong biogeographical affinities with the assemblages of the midcontinental and southern regions of the USA. Particularly, the Atokan crinoids of central Sonora are similar to those from Kansas and Texas, confirming the close palaeogeographic connection of southern USA and northern Mexico during the Middle Pennsylvanian.
Fish on Prozac: a simple, noninvasive physiology laboratory investigating the mechanisms of aggressive behavior inBetta splendens
Authors: Lynn Sharon E. , Egar Joseph M. , Walker Brian G. , Sperry Todd S. , Ramenofsky Marilyn
Published: December 2007

The neuromodulator serotonin is an important regulator of aggressive behavior in vertebrates. Experimentally increasing synaptic levels of serotonin with fluoxetine, a selective serotonin reuptake inhibitor, has been shown to reliably decrease the expression of aggressive behavior. Here, we describe a method by which fluoxetine can be noninvasively administered to male Betta splendens (an attractive model for the study of aggressive behavior) and describe a simple laboratory exercise that allows students to experimentally investigate the physiological mechanisms of aggressive behavior. We demonstrate that relatively short-term exposure (3 h) of male bettas to as little as 3 μg/ml of fluoxetine-treated aquarium water is sufficient to reduce the expression of specific aggressive behaviors. We emphasize the physiological concepts that can be addressed with this exercise, including the role of the serotonergic system in regulating aggression, and the interplay of environmental contaminants and physiology in regulating the expression of behavior. We also highlight important aspects of experimental design. This exercise can be flexibly altered to accommodate one or several laboratory periods. It is also low cost, is low impact to the animals, and requires minimal preparation time for instructors.
Career counseling: 101+ things you can do with a degree in biology
Authors: Eyster Kathleen M.
Published: December 2007

Biology is the science of life and of how living things work. Our students choose to major in biology in college because of a fascination with understanding how living things function, but often they have difficulty in identifying a career that uses their foundation in biology despite the variety of biology-based careers available. The purpose of this discussion is to assist biology students and the career counselors who work with them in identifying satisfying careers that build upon their interest and foundation in biology. The categories of career options include research, healthcare, teaching, science writing, administration/management, government, industry, and miscellaneous careers that do not fit into the other categories.
Effective use of course management systems to enhance student learning: Experimental Biology 2007
Authors: Kibble Jonathan D. , Kingsbury Jeffrey , Ramirez Beatriz U. , Schlegel Whitney M. , Sokolove Phillip
Published: December 2007

Course management systems are software packages that support teaching and learning by providing web-based tools, services, and resources. Electronic course management can facilitate course organization, teaching delivery, communication, collaboration, and assessment. This article reports on a symposium on the use of course management systems, presented by the Teaching of Physiology Section of the American Physiological Society, at the Experimental Biology Meeting of 2007.
From a pump handle to oral rehydration therapy: a model of translational research
Authors: Schultz Stanley G.
Published: December 2007

Few afflictions have attracted as much attention and impacted on as many societal and biomedical areas as cholera. Dr. John Snow's studies launched the field of epidemiology, were early applications of medical cartography, and promoted the use of statistical methods in medicine. The finding that cholera was due to the ingestion of contaminated water lent to the demise of the prevalent “miasmatic theory of contagion,” set the platform for the “germ theory of disease,” and promoted the growth of public health concerns for water purification and sanitation. More recent attention to this disease led to the notion of “secretory diarrhea” and the translation of basic principles to the development of oral rehydration therapy and its “spin-offs” (Gatorade and Pedilyte).
Interleukin-6 and cachexia inApcMin/+mice
Authors: Baltgalvis Kristen A. , Berger Franklin G. , Pena Maria Marjorette O. , Davis J. Mark , Muga Stephanie J. , Carson James A.
Published: December 2007

The ApcMin/+mouse has a mutation in the Apc tumor suppressor gene and develops intestinal polyps, beginning at 4 wk of age. This mouse develops cachexia by 6 mo, characterized by significant loss of muscle and fat tissue. The purpose of the present study was to determine the role of circulating interleukin-6 (IL-6) and the polyp burden for the development of cachexia in ApcMin/+mice. At 26 wk of age, mice exhibiting severe cachectic symptoms had a 61% decrease in gastrocnemius muscle weight, complete loss of epididymal fat, a 10-fold increase in circulating IL-6 levels, and an 89% increase in intestinal polyps compared with mildly cachectic animals. ApcMin/+/IL-6−/−mice did not lose gastrocnemius muscle mass or epididymal fat pad mass while overall polyp number decreased by 32% compared with ApcMin/+mice. Plasmid-based IL-6 overexpression in ApcMin/+/IL-6−/−mice led to a decrease in gastrocnemius muscle mass and epididymal fat pad mass and increased intestinal polyp burden. IL-6 overexpression did not induce cachexia in non-tumor-bearing mice. These data demonstrate that IL-6 is necessary for the onset of adipose and skeletal muscle wasting in the ApcMin/+mouse and that circulating IL-6 can regulate ApcMin/+mouse tumor burden.
c-myc Repression of TSC2 Contributes to Control of Translation Initiation and Myc-Induced Transformation
Authors: Ravitz Michael J. , Chen Li , Lynch Mary , Schmidt Emmett V.
Published: December 2007

The c-myc oncogene plays a key role in cellular growth control, and translation initiation factors are among the transcriptional targets of Myc. Here, we describe a defect in translation initiation control in myc-null cells due to alterations in the mammalian target of rapamycin (mTOR) pathway. Myc loss increased sensitivity to dominant inhibition of eukaryotic translation initiation factor 4E function. Polysomal profiles of myc−/− cells revealed decreased translation initiation rates, which were accompanied by decreased 40S/60S ribosomal subunit ratios. Because the 40S small ribosomal subunit contains the key regulatory ribosomal protein S6 (rpS6), we considered that myc loss might affect expression of components of the mTOR signaling pathway that regulate rpS6 function. Among mTOR signaling components, Myc directly affected transcription of tuberous sclerosis 2 (TSC2), as shown by quantitative mRNA analysis and by Myc binding to its promoter in chromatin immunoprecipitation assays. Importantly, Myc acted as a strong and direct repressor for TSC2 expression because its loss increased TSC2 mRNA in myc-null and in HL60 shRNA experiments, activation of a mycER construct in myc−/− cells suppressed TSC2 induction in a myc box II–dependent manner, and mycER activation recruited Myc to the TSC2 promoter. The biological significance of the effect of Myc on TSC2 expression was shown by markedly reduced TSC2 mRNA levels in myc-transformed cells, stimulation of S6 kinase activity in myc-null cells by TSC2 siRNA, and decreased Myc-induced soft agar colony formation following retroviral transduction of TSC2. Together, these findings show that regulation of TSC2 can contribute to the effects of Myc on cell proliferation and neoplastic growth. [Cancer Res 2007;67(23):11209–17]
Ribosomal Protein S27-like, a p53-Inducible Modulator of Cell Fate in Response to Genotoxic Stress
Authors: Li Jingsong , Tan Jing , Zhuang Li , Banerjee Birendranath , Yang Xiaojing , Chau Jenny Fung Ling , Lee Puay Leng , Hande Manoor Prakash , Li Baojie , Yu Qiang
Published: December 2007

Activation of the p53 tumor suppressor upon DNA damage elicits either cell cycle arrest or apoptosis, and the precise mechanism governing cell fate after p53 response has not been well defined. Through genomic analysis, we have identified the ribosomal protein S27-like (RPS27L) as a novel p53 transcriptional target gene. Although RPS27L mRNA levels were consistently induced after diverse p53 activating signals, its change in protein level was stimuli-dependent: it was up-regulated when cells were arrested in response to DNA-damaging agents Adriamycin or VP16 but was down-regulated when cells underwent apoptosis in response to antimetabolite agent 5-fluorouracil. RPS27L is a nuclear protein that forms nuclear foci upon DNA damage. Depletion of RPS27L resulted in deficiency in DNA damage checkpoints, leading to conversion of DNA damage–induced p53 response from cell cycle arrest to apoptosis. We further show that RPS27L positively regulates p21 protein expression. Through this mechanism, RPS27L induction by p53 facilitates p21-mediated cell cycle arrest and protects against DNA damage–induced apoptosis. Thus, RPS27L modulates DNA damage response and functions as a part of the control switch to determine cell fate to DNA damage–p53 response. [Cancer Res 2007;67(23):11317–26]
Histone Deacetylase Inhibitors Promote the Tumoricidal Effect of HAMLET
Authors: Brest Patrick , Gustafsson Mattias , Mossberg Ann-Kristin , Gustafsson Lotta , Duringer Caroline , Hamiche Ali , Svanborg Catharina
Published: December 2007

Histone deacetylase inhibitors (HDIs) and HAMLET (human α-lactalbumin made lethal to tumor cells) interact with histones, modify the structure of chromatin, and trigger tumor cell death. This study investigated how the combination of HDIs and HAMLET influences cell viability, histone acetylation, and DNA integrity. The pretreatment of tumor cells with HDIs was shown to enhance the lethal effect of HAMLET and the histone hyperacetylation response to HDIs increased even further after HAMLET treatment. HDIs and HAMLET were shown to target different histone domains as HAMLET bound tailless core histones, whereas HDIs modify the acetylation of the histone tail. DNA damage in response to HAMLET was increased by HDIs. The DNA repair response (p21WAFI expression) was induced by both agonists but abolished when the two agonists were combined. The results suggest that the synergy of HDIs and HAMLET is based on different but converging death pathways, both involving chromatin alterations. We speculate that HAMLET and HDIs might be combined to promote tumor cell death in vivo. [Cancer Res 2007;67(23):11327–34]