bluuebunny/crossref_metadata_2025 huggingface dataset:
Desiccation of imbibed and germinating pea axes causes a partial reversal of germination events
Authors: Lalonde Louise , Bewley J. Derek
Published: May 2010

During the first 20 h of imbibition, the viability of ungerminated pea seeds was progressively impaired by desiccation, although by no more than about 15%. However, a drastic reduction in radicle growth and viability resulted if the seeds were imbibed for 24 h or longer before dehydration to 5% moisture content (but not if drying was to 10% moisture content or greater). Therefore, pea seeds undergo a transition from a desiccation-tolerant to a desiccation-intolerant state between 20 and 24 h after the start of imbibition. Seeds initially imbibed for 8, 12, and 16 h and desiccated to their original moisture content completed germination in a shorter time than control (once-imbibed) seeds. However, a residual effect of the treatment was noted, in that the total imbibition time required before germination was longer in those seeds that had been subjected to desiccation between periods of imbibition. Hence, events occurring prior to water loss are not completely stable to desiccation and are partially reversed. Axes from germinating seeds interrupted by a desiccation treatment retained some of their capacity to synthesize proteins. This metabolic event thus responded to desiccation in a similar manner to a physiological parameter, i.e., the rate of germination.
Dioecy and pollen dimorphism in Vitis riparia (Vitaceae)
Authors: Kevan Paeter G. , Longair Robert W. , Gadawski Randy M.
Published: May 2010

The breeding system of Vitis riparia Michx. hitherto has not been investigated. Field observations indicated that two morphs exist, one that produces fruit, and another that does not. Through experimental cross- and self-pollinations it was found that V. riparia is functionally dioecious in southern Ontario. Further, it was found that male plants produce functional spherical tricolporate pollen, whereas female plants produce inaperturate pollen of the same diameter, 23 μm, that cannot bring about fertilization. The sex ratios found at seven locations were skewed slightly, but significantly, in favour of male plants (average 0.567). Pollination is brought about by wind, probably supplemented to a greater or lesser extent by insects which feed on the cytoplasm-filled pollen of both sexes.
Vesicular–arbuscular mycorrhizal (Glomus fasciculatum) influence on soybean drought tolerance in high phosphorus soil
Authors: Busse M. D. , Ellis J. R.
Published: May 2010

Vesicular–arbuscular mycorrhizal fungi (VAM) may enhance growth of nonirrigated soybean (Glycine max (L.) Merr.) by improving host drought tolerance. The purpose of this study was to determine growth and yield response of drought-stressed soybean to infection by the mycorrhizal endophyte Glomus fasciculatum. Plants were grown in the greenhouse in Kennebec silt loam soil (fine silty, mixed, mesic, Cumulic Hapludoll). The treatments included the presence or absence of both G. fasciculatum and drought stress, arranged in a 2 × 2 factorial design (12 replications). To create stress treatments, water was withheld for 9 d during the pod elongation stage, and half of the plants were harvested immediately after the stress period and half at physiological seed maturity. Plants harvested immediately after stress (51 d after emergence) had significant reduction in mycorrhizal infection and soybean nodulation. The root-to-shoot ratio of stressed plants inoculated with VAM decreased 24% compared with noninoculated plants, indicating enhanced host drought tolerance by G. fasciculatum. Total seed weight of stressed plants increased 10% when infected with VAM as a result of reduced pod abortion. Significant G. fasciculatum × drought stress interactions were found for total seed weight, pod number, seed number, and root-to-shoot ratio, showing that G. fasciculatum had a more positive effect on drought-stressed compared with control plants. Transpiration rates during the stress period were similar for infected and noninfected plants. Enhanced yield of infected plants may have been the result of improved P nutrition or more extensive soil water extraction. The results of this experiment show potential benefits of VAM colonization in soybean in arid and semiarid regions.
Keldysh theory of strong-field ionization
Authors: Long Zi Jian , Liu Wing-Ki
Published: May 2010

In this paper, we provide a detailed derivation of the strong-field ionization rates originally developed by Keldysh who introduced the strong-field approximation. Numerical results are presented to examine the saddle-point approximation, the low photoelectron energy approximation, and neglecting the interference terms, which are necessary to arrive at the simple quasistatic result, when the Keldysh parameter becomes very small.
Estimation of acoustic nonlinearity parameter and molecular characteristics of ternary liquid mixtures at different temperatures
Authors: Tripathi Bhawana S. , Awasthi Anjali , Awasthi Aashees
Published: May 2010

The acoustic nonlinearity parameter (B/A) of ternary liquid mixtures of heterocyclic compounds viz. pyridine and quinoline with phenol in benzene has been evaluated at 308.15, 318.15, and 328.15 K by three different methods viz. Tong–Dong method, Beyer’s method, and Beyer’s method using Tong–Dong coefficients. The molecular interactions in the liquid mixtures are explained on the basis of excess nonlinearity parameter ((B/A)E). Sehgal’s relations for calculating the molecular properties for pure liquids are extended to the ternary liquid mixtures.
Nonlinear generation of non-acoustic modes by low-frequency sound in a vibrationally relaxing gas
Authors: Perelomova Anna
Published: May 2010

Two dynamic equations referring to a weakly nonlinear and weakly dispersive flow of a gas in which molecular vibrational relaxation takes place, are derived. The first one governs an excess temperature associated with the thermal mode, and the second one describes variations in vibrational energy. Both quantities refer to non-wave types of gas motion. These variations are caused by the nonlinear transfer of acoustic energy into thermal mode and internal vibrational degrees of freedom of a relaxing gas. The final dynamic equations are instantaneous; they include a quadratic nonlinear acoustic source, reflecting the nonlinear character of interaction of low-frequency acoustic and non-acoustic motions of the fluid. All types of sound, periodic or aperiodic, may serve as an acoustic source of both phenomena. The low-frequency sound is considered in this study. Some conclusions about temporal behavior of non-acoustic modes caused by periodic and aperiodic sound are made. Under certain conditions, acoustic cooling takes place instead of heating .
Radiation pressure on a dielectric surface
Authors: Hirose A.
Published: May 2010

The radiation pressure on an insulating dielectric medium should be calculable from the force acting on the polarization vector P. The well-known force proposed by Gordon (Phys. Rev. A, 8, 14 (1973) disappears in the case of a steady-state plane wave. A new form of force explicitly involving the polarization vector is proposed and applied to determine the partition of the incident momentum among the reflected and transmitted wave, and the dielectric medium. The momentum of electromagnetic wave in a dielectric medium thus found is consistent with the classical relationship, wave momentum flux density = wave intensity/wave velocity.
Phase-sensitive particle separation using alternating longitudinal electric field
Authors: Mohazzabi Pirooz , Greenebaum Ben
Published: May 2010

Particles with different charge-to-mass ratios can be separated in a phase-sensitive process with application of a simple alternating longitudinal electric field in the absence of other electric or magnetic fields. The method suggests that a given particle can either be isolated or eliminated from a beam of several charged particles, in contrast to the conventional mass spectrometry where a particular particle is isolated. The method, based on the principles underlying phase stability in particle accelerators, could be applied to mass spectrometry or selective ion sources for plasma generation, ion traps, sputtering, or other applications. It would be especially useful in instances where the incoming ions are timed in synchrony with the proper phase of the applied voltage.
Fermion tunneling effect in Vaidya-de Sitter space
Authors: Qi De-Jiang , Wang Wei-Min , Li Shuang-Mei
Published: May 2010

In this paper, by considering energy conservation and the self-gravitation reaction in the dynamical background space-time, we attempt to extend Kerner and Mann's work to the Vaidya–de Sitter black hole by the fermion-tunneling method. The result we derive shows that the tunneling probability of the Vaidya–de Sitter black hole is related not only to the change in the Bekenstein–Hawking entropy but also to the integral of the changing horizon, which are different from the stationary cases.
Growth and mortality following partial cutting in a trembling aspen – conifer stand: results after 10 years
Authors: Prévost Marcel , Dumais Daniel , Pothier David
Published: May 2010

We present the effects, 10 years after treatment, of different cutting intensities (removal of 0%, 35%, 50%, 65%, and 100% of basal area (BA)) on the response of residual trees in a 60-year-old mixed aspen–conifer stand in Quebec, Canada. While decennial mortality reached 170 stems·ha–1 under natural conditions (control, 24 m2·ha–1 BA), the removal of mature trembling aspen ( Populus tremuloides Michx.) trees reduced hardwood losses to 125, 105, and 0 stems·ha–1, respectively, in the 35%, 50%, and 65% cuttings, without affecting losses of coniferous species (≤25 stems·ha–1). The growth response of conifers was generally higher than that of broad-leaved species. For hardwoods, the decennial gains in merchantable BA decreased with respect to the control (3.2 m2·ha–1), to 1.2 m2·ha–1 in the 35% cut and to 0.9 m2·ha–1 in the 50% cut, but increased under the 65% cut (2.5 m2·ha–1). For conifers, gains were proportional to removal in partial cuts (2.6–4.9 m2·ha–1) and lower in the control (1.7 m2·ha–1). As a whole, our results suggest that partial cutting may be an effective means of increasing growth of the softwood proportion occupying the intermediate and suppressed strata in a mixed aspen-dominated stand.
Frequency of root grafting in naturally and artificially regenerated stands of Pinus banksiana: influence of site characteristics
Authors: Tarroux Emilie , DesRochers Annie
Published: May 2010

We investigated the frequency of root grafting in naturally and artificially regenerated stands of jack pine ( Pinus banksiana Lamb.) in the western boreal forest of Quebec, Canada. Twelve 30–60 m2 plots were hydraulically excavated to determine effects of site characteristics on frequency and timing of root grafting. Naturally regenerated stands had grafted tree percentages similar to artificially regenerated stands (21%–71% across plots) but greater numbers of root grafts per tree (naturally regenerated, 0.73 graft·tree–1; artificially regenerated, 0.52 graft·tree–1). Mean percentages of grafted trees, number of grafts per tree, and the speed of graft formation were greater in sandy soils (61%, 0.71 graft·tree–1 and 2.43 years, respectively) compared with clay soils (44%, 0.54 graft·tree–1 and 2.97 years, respectively). Proximity of trees was a better predictor of root grafting than stand density, despite many root grafts being found with distant trees (>2 m) in artificially regenerated stands. Our results suggested that root grafts form early in stand development. Even if trees are initially separate entities, this relatively high level of root grafting produces stands where trees are extensively interconnected.
Growth, yield, and structure of extended rotation Pinus resinosa stands in Minnesota, USA
Authors: D’Amato Anthony W. , Palik Brian J. , Kern Christel C.
Published: May 2010

Extended rotations are increasingly used to meet ecological objectives on forestland; however, information about long-term growth and yield of these systems is lacking for most forests in North America. Additionally, long-term growth responses to repeated thinnings in older stands have received little attention. We addressed these needs by examining the growth and yield of red pine ( Pinus resinosa Ait.) in a growing stock experiment in northern Minnesota. Stands were 85 years old at the onset of this experiment and were repeatedly thinned to five levels of basal area (13.8, 18.4, 23.0, 27.5, and 32.1 m2·ha–1) over 58 years. Cumulative volume production and volume growth were lowest within the lowest stocking treatment and similar across other stocking levels. Late-successional structural attributes, such as the density of trees with ≥40 cm diameter at breast height, was similar across stocking levels. The mean annual volume growth culminated between 130 and 140 years. Additionally, positive growth responses were observed within the highest stocking-level treatments after thinning at 138 years, demonstrating the ability of older red pine to respond to reductions in competition. These results illustrate that extended rotations with repeated thinnings in red pine help achieve ecological goals, including the restoration of old-forest structure, while also maintaining high levels of stand productivity.
Equity pricing in the forest sector: evidence from North American stock markets
Authors: Niquidet Kurt
Published: May 2010

Financial capital is very mobile and the failure to earn the cost of capital can result in capital flight and a considerably altered forest industry. This article seeks to assess the cost of equity capital for the forest sector from a modern finance perspective and test to what extent it has earned the cost of this capital over the period spanning from December 2003 to December 2008. To do so, using time series and cross-sectional methods, the capital asset pricing model and the Fama–French three-factor model were applied to the weekly returns of 45 publicly traded forest sector securities that are listed on North American stock exchanges. The time series results for both the capital asset pricing and Fama–French three-factor models yielded several negative pricing errors, suggesting ex post that many firms in the sector have failed to earn the cost of equity. Furthermore, cross-sectional results show that riskier firms tended to have lower returns. Such findings are unlikely to hold in the long run and could be one of the primary factors driving significant change in the forest sector in the future.
NEGATIVE ENERGY DENSITIES IN QUANTUM FIELD THEORY
Authors: FORD L. H.
Published: May 2010

Quantum field theory allows for the suppression of vacuum fluctuations, leading to sub-vacuum phenomena. One of these is the appearance of local negative energy density. Selected aspects of negative energy will be reviewed, including the quantum inequalities which limit its magnitude and duration. However, these inequalities allow the possibility that negative energy and related effects might be observable. Some recent proposals for experiments to search for sub-vacuum phenomena will be discussed. Fluctuations of the energy density around its mean value will also be considered, and some recent results on a probability distribution for the energy density in two dimensional spacetime are summarized.
INTEGRATED SECURITY FRAMEWORK FOR INDUSTRIAL R&D ENVIRONMENTS
Authors: KIM SANGKYUN
Published: May 2010

As use of information systems in R&D environments has increased enormously, the risks of technology leakage through information systems have become more serious. To provide a basic guideline of R&D security which helps enterprise executives to solve the managerial problems of R&D security planning is a purpose of this paper. This paper provides an integrated security framework including R&D security goal, R&D-related division and activity, and pool of controls. With the integrated security framework suggested in this paper, an enterprise that invests hundreds of thousands of dollars to develop a new product can adapt itself to mitigate security risks and reduce potential losses of technology leakage. It could be believed to be the first attempt to provide the R&D-specific security framework for enterprise executives to solve the security problems in R&D environments.
EDITORIAL: A GENERAL FRAMEWORK FOR SLOW INTELLIGENCE SYSTEMS
Authors: CHANG SHI-KUO
Published: May 2010

Contrary to popular belief, not all intelligent systems have Quick Intelligence. There are a surprisingly large number of intelligent systems, quasi-intelligent systems and semi-intelligent systems that have Slow Intelligence. Such Slow Intelligence Systems are often neglected in mainstream research on intelligent systems, but they are really worthy of our attention and emulation. I will describe the characteristics of Slow Intelligence Systems and present a general framework for Slow Intelligence Systems. I will then discuss evolutionary query processing and mission control in emergency management systems as two examples of Artificial Slow Intelligence Systems. Researchers and practitioners are both invited to explore the applications of Slow Intelligence Systems in software engineering and knowledge engineering, and publish their findings in IJSEKE.
ASSESSING TEST SUITES FOR BUFFER OVERFLOW VULNERABILITIES
Authors: SHAHRIAR HOSSAIN , ZULKERNINE MOHAMMAD
Published: May 2010

Over the last few years, numerous vulnerabilities have been reported in software, and successful exploitations of these vulnerabilities have resulted in severe consequences such as denial of services and application state corruptions. Researches have shown that effective quality assurance methods can prevent such consequences when applied during software (or applications) development processes. Software security testing is a popular assurance method in this direction. However, effective testing involves obtaining an effective test suite (or collection of test cases) that can reveal specific faults. Over the last few years, different testing approaches have been applied for revealing vulnerabilities in software. However, only few works have assessed the effectiveness of test suites for revealing vulnerabilities. We believe that bringing the idea of mutation-based assessment of test adequacy for vulnerabilities can help in detecting and removing vulnerabilities proactively. In this work, we apply mutation-based adequate testing for one of the worst vulnerabilities namely buffer overflow (BOF). We propose 16 mutation operators to force the generation of adequate test suites for BOF vulnerabilities. A prototype tool is developed to automatically generate mutants and perform mutation analysis with input test cases. The effectiveness of the operators is evaluated by using several benchmark programs having BOF vulnerabilities, and the results indicate that the proposed operators are effective for testing BOF vulnerabilities. Moreover, we present an analysis to find selective mutation operators for reducing the cost of mutation-based testing of BOF vulnerabilities.
SOFTWARE QUALITY EVALUATION FOR SECURITY COTS PRODUCTS
Authors: VILLALBA M. TERESA , FERNÁNDEZ-SANZ LUIS , CUADRADO-GALLEGO JUAN J. , MARTÍNEZ JOSE J.
Published: May 2010

Increasing demand for security commercial products requires an improvement of methods for evaluating their software quality. Existing standards offer general frameworks but more specific models which reflect the perception of experts and customers as well as the particular characteristics of this type of products are needed. This article presents a method for generating domain-oriented software quality models for specific types of applications. It is applied to the generation of a model for security COTS products based on systematic review of standards, related literature and conclusions of evaluation experiences as well as the statistical analysis of information collected from 203 security experts and practitioners. Results reveal interesting conclusions on the importance given by users to the different quality characteristics of security commercial software products.
AUTOMATING ACTUALISATION OF GEOGRAPHIC INFORMATION USING THE TWOFOLD FUZZY REGION MODEL
Authors: CHARLIER NIELS , DE TRÉ GUY , GAUTAMA SIDHARTA , BELLENS RIK
Published: May 2010

In this paper a new method is proposed for automating quality control and actualisation of spatial information using image data. A new model for imperfect geographic information is explored for this purpose: a twofold fuzzy region model; which is an extension of both the fuzzy region model and the egg/yolk model. This model is used to interpret spatial classifications and its imperfections in a new way. By defining different operators on the model an imprecise quality report can be developped for geographic databases that uses the imperfect spatial classification as reference information. The model makes it possible, despite the large amount of imperfection in spatial classifications, to use them for rather accurate error detection on geographic databases.
BOUNDED LINEAR PROGRAMS WITH TRAPEZOIDAL FUZZY NUMBERS
Authors: EBRAHIMNEJAD ALI , NASSERI SEYED HADI , LOTFI FARHAD HOSSEINZADEH
Published: May 2010

Recently Ganesan and Veeramani introduced a new approach for solving a kind of linear programming problems involving symmetric trapezoidal fuzzy numbers without converting them to the crisp linear programming problems. But their approach is not efficient for situations in which some or all variables are restricted to lie within fuzzy lower and fuzzy upper bounds. In this paper, by a natural extension of their approach we obtain some new results leading to a new method to overcome this shortcoming.
INTERVAL METHODS IN KNOWLEDGE REPRESENTATION
Authors: Kreinovich Vladik
Published: May 2010

This section is maintained by Vladik Kreinovich. Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to: Vladik Kreinovich, Department of Computer Science, University of Texas, El Paso, TX 79968, USA.
AN AVAILABILITY MODEL FOR STORAGE PRODUCTS UNDER PERIODICAL INSPECTIONS
Authors: CUI LIRONG , ZHAO XIAN , SHEN JIANBO , XU YU
Published: May 2010

A maintenance model is built under some assumptions which come from the real situation for storage products under periodical inspections. The similar model was discussed by Kijima14 when the periodical interval becomes zero, i.e., for the non-periodical inspection case. In Kijima's model, for the product's instantaneous availability, A(t), the probability that the storage products can work in time t, is one. However, it is not easy to get the instantaneous availability in our model, because of periodical inspections. After using the virtual age concept and several lemmas gotten, we, with closed-form for the storage products, present the instantaneous availability and the limiting average availability. Finally, an example is shown to illustrate the results.
OPTIMAL REORGANIZATION SCHEDULES OF STRUCTURAL DATABASE DETERIORATION
Authors: NAKAMURA SYOUJI , NAKAYAMA KEIKO , NAKAGAWA TOSHIO
Published: May 2010

Both response time and processing time become recently big problems in the processing time of various online and batch systems. Especially, the access efficiency of the database should be greatly controlled as for the speed of the processing time of accesses to the database. Because records are inserted far from their logical position, the storages of deleted records occupy some diverse spaces in the database. Then, to cover the weak point of the database, we execute the database reorganization at suitable times to achieve a good performance requirement for the application. There are two types purposes of the database reorganization: The purpose of physical reorganization is to optimize the database storage and to improve the database structure. However, as the database has usually access locality, its data structure may deterirate in limited parts of the storage space. Thus, we adop the partial reorganization. This reorganizes only locally structurally deteriorated space in the database, while the structural efficiency can be recovered similarly to the full reorganization. This paper considers two structural deteriorations which increase with time and occur independently in time. When the amount of deterioration is estimated at periodic time and at a specified time, the expected cost rates are obtained, using the cumulative damage model, and optimal policies which minimize them are discussed and analytically. We compute optimal policies for two models and compare them numeically.
SCALABLE QUANTUM NETWORKS BASED ON FEW-QUBIT REGISTERS
Authors: JIANG LIANG , TAYLOR JACOB M. , SØRENSEN ANDERS S. , LUKIN MIKHAIL D.
Published: May 2010

We describe and analyze a hybrid approach to scalable quantum computation based on an optically connected network of few-qubit quantum registers. We show that probabilistically connected five-qubit quantum registers suffice for deterministic, fault-tolerant quantum computation even when state preparation, measurement, and entanglement generation all have substantial errors. We discuss requirements for achieving fault-tolerant operation for two specific implementations of our approach.
INNOVATION IN ARTWORKS AND ITS RECEPTION: A PHENOMENOLOGICAL APPROACH
Authors: YU FU-LAI TONY
Published: May 2010

This paper seeks to explain the reception of a novel idea in artworks from a phenomenological perspective, with special reference to creativity in oil painting. It argues that whether a new idea in artwork is accepted or not by the community is a matter of subjective interpretation. Based on human agency theories put forwarded by Max Weber and Alfred Schutz, this paper uses the concept of intersubjective understanding to explain how innovative works are interpreted and accepted by the community. The phenomenological approach to understand an artwork is illustrated by oil paintings of Pablo Picasso and Vincent van Gogh.
ACHIEVING MANUFACTURING FLEXIBILITY: THE ROLE OF PEOPLE, TECHNOLOGY, INNOVATION AND CONTINUOUS IMPROVEMENT
Authors: JUDI HAIRULLIZA MOHAMAD , BEACH ROGER
Published: May 2010

This study examines the contribution of a pair of opposite factors: technology versus people, and innovation vs. continuous improvement to obtain manufacturing flexibility. These factors are opposing as they play different roles in TQM and BPR. An exploratory multiple case study was conducted that involves three Malaysian manufacturing companies from electronic and electric sector. The results show that flexibility could not be achieved through technology solely, but by combining technology with people, the required outcome is attainable. By applying innovation and continuous improvement simultaneously, it will yield better flexibility than if only one of them was used. The contribution of these factors in the selected manufacturing setting could guide practitioners to obtain flexibility and verify the research model that could be tested further in a survey.
Polymetallic auriferous vein mineralization near Loch Tay, Perthshire, Scotland
Authors: Corkhill Claire , Ixer Robert A. F. , Mason John S. , Irving Duncan , Pattrick Richard A. D.
Published: May 2010

Synopsis

Vein mineralization hosted by NW-trending joints at Tombuie near Loch Tay, Central Grampians contains base metal sulphides with Au, Bi, Ag and Te bearing phases associated with relatively late stage galena-dominated mineralization. Minerals present include mercurian electrum, tetradymite, altaite, rucklidegeite, hessite and argentian tetrahedrite. The mineralization is similar to that at Calliachar–Urlar and other mineralized localities in the region that form a small metallogenic province partially defined by a Bi stream sediment anomaly.
A new demosponge,
Choiaella scotica
, from the Caradoc (Ordovician) of Wallace's Cast, Southern Uplands
Authors: Beresi Matilde S. , Botting Joseph P. , Clarkson Euan
Published: May 2010

Synopsis

Two specimens of a new choiid demosponge,
Choiaella scotica
sp. nov., have been identified in the collections of the National Museums of Scotland. This is one of very few post-Cambrian records for the family, and only the second from Scotland. Both Scottish records occur in fine sandstones of shallow-water origin, but in probably different depositional environments, with the new specimens being transported into deeper water. It is possible that this group was abundant and widespread in shallow-water siliciclastic environments during the Early Palaeozoic, but its record has been limited by the low preservation potential of these habitats. The taxonomy of Choiidae is discussed, with the emphasis on establishing potentially useful diagnostic features for future discoveries.
Rhenium–Osmium (Re–Os) molybdenite systematics and geochronology of the Cruachan Granite skarn mineralization, Etive Complex: implications for emplacement chronology
Authors: Porter Sarah J. , Selby David
Published: May 2010

Synopsis

New Re–Os molybdenite geochronology yields the absolute timing (414.6 ± 2.1 and 414.7 ± 2.1 Ma) of Skarn-type mineralization associated with the Cruachan Granite of the Etive Complex at Coire Buidhe, Glencoe, Scotland. The Re–Os dates agree with recent U–Pb zircon geochronology (414.9 ± 0.7 Ma;

Neilson
et al
. 2009

) for the host pluton indicating that the mineralization is genetically related to the Cruachan Granite and that the Re–Os dates provide a minimum emplacement timing for the granite. Combined, the new Re–Os and U–Pb dates demonstrate that the crystallization of the Gruachan Granite occurred
c
. 10 Ma earlier than previously thought.
Developmental anomalies on the skull of the Scottish Middle Devonian lungfish
Pinnalongus saxoni
Authors: Newman Michael J. , Den Blaauwen Jan L.
Published: May 2010

Synopsis

A new specimen of the recently described dipnoan fish,
Pinnalongus saxoni
Newman & den Blaauwen, 2007
from the Scottish Middle Devonian has been collected in Achastle-shore, eastern Caithness. This new specimen whilst consisting of only a head, has many new features not previously described in
P. saxoni
, such as the lateral line system of the head which is shown to conform to the well known form
Dipterus
, also from the Middle Devonian of Scotland. The specimen also has features not seen before in any fossil fish such as the ring-like structures associated with pore openings, plus an unusual development of the cosmine cover at the rear of the skull. The presence of both
Coccosteus
and
Thursius
in the same deposits confirms that Achastle-shore in situated below the well-known Achanarras fish bed horizon and suggests that
P. saxoni
could be used as a zone fossil.
Tree trunks of
Pitus primaeva
in Mississippian (Courceyan) rocks at Montford, near Rothesay, Isle of Bute, Scotland
Authors: Falcon-Lang Howard J. , Henderson Elsa , Galtier Jean
Published: May 2010

Synopsis

Silicified tree trunks are described for the first time from Montford, near Rothesay, Isle of Bute, Scotland. The fossils occur in a fault-bounded succession, which is probably part of the Mississippian (Courceyan) Kinnesswood Formation. Quantitative anatomical analysis indicates that the tree trunks belong to the arborescent pteridosperm,
Pitus primaeva
Witham. Growth interruptions preserved in branches imply that these trees experienced aperiodic water stress, perhaps reflecting monsoonal seasonality in this part of palaeoequatorial Laurasia.
Chromatin Dynamics
Authors: Hübner Michael R. , Spector David L.
Published: May 2010

The expression patterns of many protein-coding genes are orchestrated in response to exogenous stimuli, as well as cell-type-specific developmental programs. In recent years, researchers have shown that dynamic chromatin movements and interactions in the nucleus play a crucial role in gene regulation. In this review, we highlight our current understanding of the organization of chromatin in the interphase nucleus and the impact of chromatin dynamics on gene expression. We also discuss the current state of knowledge with regard to the localization of active and inactive genes within the three-dimensional nuclear space. Furthermore, we address recent findings that demonstrate the movements of chromosomal regions and genomic loci in association with changes in transcriptional activity. Finally, we discuss the role of intra- and interchromosomal interactions in the control of coregulated genes.
Lessons Learned from UvrD Helicase: Mechanism for Directional Movement
Authors: Yang Wei
Published: May 2010

How do molecular motors convert chemical energy to mechanical work? Helicases and nucleic acids offer simple motor systems for extensive biochemical and biophysical analyses. Atomic resolution structures of UvrD-like helicases complexed with DNA in the presence of AMPPNP, ADP·Pi, and Pi reveal several salient points that aid our understanding of mechanochemical coupling. Each ATPase cycle causes two motor domains to rotationally close and open. At a minimum, two motor-track contact points of alternating tight and loose attachment convert domain rotations to unidirectional movement. A motor is poised for action only when fully in contact with its track and, if applicable, working against a load. The orientation of domain rotation relative to the track determines whether the movement is linear, spiral, or circular. Motors powered by ATPases likely deliver each power stroke in two parts, before and after ATP hydrolysis. Implications of these findings for analyzing hexameric helicase, F1F0 ATPase, and kinesin are discussed.
Neurometabolic Coupling in the Lateral Geniculate Nucleus Changes With Extended Age
Authors: Li Baowang , Freeman Ralph D.
Published: May 2010

Attempts have been made in various studies to identify and trace changes in function in the aging visual system. Some results are conflicting and we report here a unique approach in an attempt to resolve selected issues. We have estimated neurometabolic coupling in the central visual pathway in young and old cats. Our technique provides high resolution simultaneous measurements of neuronal activity and changes in concentration of tissue oxygen in the thalamus of young and old cats. Following visual stimulation, we find shorter latency and time to peak in tissue oxygen responses in old compared with young animals. Estimates of local activity induced initial negative oxygen response show substantial reductions in older animals. Measurements of neural activity in the form of multiple unit activity are similar in the two age groups. To investigate the mechanisms underlying the changes in tissue oxygen response in older animals, we measured vascular capillary density and found it to be substantially lower in old than that in young animals. Together, these findings suggest that the changes in metabolic responses with age may be largely accounted for by alterations in the cerebral microvasculature rather than by changes in neural activity.
Sarcomere Control Mechanisms and the Dynamics of the Cardiac Cycle
Authors: Solaro R. John
Published: May 2010

This review focuses on recent developments in the molecular mechanisms by which Ca activates cardiac sarcomeres and how these mechanisms play out in the cardiac cycle. I emphasize the role of mechanisms intrinsic to the sarcomeres as significant determinants of systolic elastance and ventricular stiffening during ejection. Data are presented supporting the idea that processes intrinsic to the thin filaments may promote cooperative activation of the sarcomeres and be an important factor in maintaining and modifying systolic elastance. Application of these ideas to translational medicine and rationale drug design forms an important rationale for detailed understanding of these processes.
Safety and Efficacy of Erythropoietin in Traumatic Brain Injury Patients: A Pilot Randomized Trial
Authors: Nirula R. , Diaz-Arrastia R. , Brasel K. , Weigelt J. A. , Waxman K.
Published: May 2010

Background. Erythropoietin (EPO) is a neuroprotective agent utilized in stroke patients. This pilot study represents the first randomized trial of EPO in traumatic brain injury (TBI) patients.Methods. Adult, blunt trauma patients with evidence of TBI were randomized to EPO or placebo within 6 hours of injury. Baseline and daily serum S-100B and Neuron Specific Enolase (NSE) levels were measured.Results. TBI was worse in the EPO (n=11) group compared to placebo patients (n=5). The use of EPO did not impact NSE (P=.89) or S100 B (P=.53) levels compared to placebo.Conclusions. At the dose used, EPO did not reduce neuronal cell death compared to placebo; however, TBI severity was worse in the EPO group while levels of NSE and S100-B were similar to the less injured placebo group making it difficult to rule out a treatment effect. A larger, balanced study is necessary to confirm a potential treatment effect.
Mouse Models for Blistering Skin Disorders
Authors: Ganeshan Radhika , Chen Jiangli , Koch Peter J.
Published: May 2010

Genetically engineered mice have been essential tools for elucidating the pathological mechanisms underlying human diseases. In the case of diseases caused by impaired desmosome function, mouse models have helped to establish causal links between mutations and disease phenotypes. This review focuses on mice that lack the desmosomal cadherins desmoglein 3 or desmocollin 3 in stratified epithelia. A comparison of the phenotypes observed in these mouse lines is provided and the relationship between the mutant mouse phenotypes and human diseases, in particular pemphigus vulgaris, is discussed. Furthermore, we will discuss the advantages and potential limitations of genetically engineered mouse lines in our ongoing quest to understand blistering skin diseases.
New Design Method of UWB Microstrip Filters Using Adaptive Genetic Algorithms with Defected Ground Structures
Authors: Dastkhosh Amir Reza , Dadashzadeh Gholamreza , Sedaaghi Mohammad Hossein
Published: May 2010

The effects of adaptive genetic algorithms (AGAs) and defected ground structures (DGSs) on performance optimization of tapered microstrip filter are investigated. The proposed structure achieves an ultra wide stopband with high attenuation within a small surface area, as well as 45% smaller size, in comparison with conventional filters. The parameters of the filter are optimized using in-home AGA code. In the proposed AGA algorithm, the crossover and mutation probabilities are adaptively changed according to the value of individual fitness. Then by utilizing the proposed DGS, a compact S-band lowpass filter with ultra-wide spurious free window is obtained. The proposed filter achieves an insertion loss of 0.8 dB from DC up to 4 GHz and 21 dB rejection in the stopband from 4.3 up to 60 GHz. The fabricated and measured results exhibit good agreement with the simulated results. They demonstrate that combining AGA and DGS yields best possible response for this group of filters.
A Set of Axioms for the Degree of a Tangent Vector Field on Differentiable Manifolds
Authors: Furi Massimo , Pera MariaPatrizia , Spadini Marco
Published: May 2010

Given a tangent vector field on a finite-dimensional real smooth manifold, its degree (also known as characteristic or rotation) is, in some sense, an algebraic count of its zeros and gives useful information for its associated ordinary differential equation. When, in particular, the ambient manifold is an open subset "Equation missing" of "Equation missing", a tangent vector field "Equation missing" on "Equation missing" can be identified with a map "Equation missing", and its degree, when defined, coincides with the Brouwer degree with respect to zero of the corresponding map "Equation missing". As is well known, the Brouwer degree in "Equation missing" is uniquely determined by three axioms called Normalization, Additivity, and Homotopy Invariance. Here we shall provide a simple proof that in the context of differentiable manifolds the degree of a tangent vector field is uniquely determined by suitably adapted versions of the above three axioms.
Bioinformatics in New Generation Flavivirus Vaccines
Authors: Koraka Penelope , Martina Byron E. E. , Osterhaus Albert D. M. E.
Published: May 2010

Flavivirus infections are the most prevalent arthropod-borne infections world wide, often causing severe disease especially among children, the elderly, and the immunocompromised. In the absence of effective antiviral treatment, prevention through vaccination would greatly reduce morbidity and mortality associated with flavivirus infections. Despite the success of the empirically developed vaccines against yellow fever virus, Japanese encephalitis virus and tick-borne encephalitis virus, there is an increasing need for a more rational design and development of safe and effective vaccines. Several bioinformatic tools are available to support such rational vaccine design. In doing so, several parameters have to be taken into account, such as safety for the target population, overall immunogenicity of the candidate vaccine, and efficacy and longevity of the immune responses triggered. Examples of how bio-informatics is applied to assist in the rational design and improvements of vaccines, particularly flavivirus vaccines, are presented and discussed.
Contractive-Like Mapping Principles in Ordered Metric Spaces and Application to Ordinary Differential Equations
Authors: Caballero J , Harjani J , Sadarangani K
Published: May 2010

The purpose of this paper is to present a fixed point theorem for generalized contractions in partially ordered complete metric spaces. We also present an application to first-order ordinary differential equations.
A Role for BAF57 in Cell Cycle–Dependent Transcriptional Regulation by the SWI/SNF Chromatin Remodeling Complex
Authors: Hah Nasun , Kolkman Annemieke , Ruhl Donald D. , Pijnappel W.W.M. Pim , Heck Albert J.R. , Timmers H.Th. Marc , Kraus W. Lee
Published: May 2010

The SWI/SNF complex is an ATP-dependent chromatin remodeling complex that plays pivotal roles in gene regulation and cell cycle control. In the present study, we explored the molecular functions of the BAF57 subunit of SWI/SNF in cell cycle control via transcriptional regulation of cell cycle–related genes. We affinity purified SWI/SNF from HeLa cells stably expressing FLAG-tagged BAF47/Ini1 with or without stable short hairpin RNA–mediated knockdown of BAF57. The subunit composition of the holo-SWI/SNF and BAF57-depleted SWI/SNF complexes from these cells was determined using a quantitative SILAC (stable isotope labeling by amino acids in cell culture)–based proteomic approach. Depletion of BAF57 resulted in a significant codepletion of BAF180 from the SWI/SNF complex without decreasing total cellular BAF180 levels. In biochemical assays of SWI/SNF activity, the holo-SWI/SNF and BAF57/BAF180-depleted SWI/SNF complexes exhibited similar activities. However, in cell proliferation assays using HeLa cells, knockdown of BAF57 resulted in an accumulation of cells in the G2-M phase, inhibition of colony formation, and impaired growth in soft agar. Knockdown of BAF57 also caused transcriptional misregulation of various cell cycle–related genes, especially genes involved in late G2. Collectively, our results have identified a new role for BAF57 within the SWI/SNF complex that is required for (a) maintaining the proper subunit composition of the complex and (b) cell cycle progression through the transcriptional regulation of a subset of cell cycle–related genes. Cancer Res; 70(11); 4402–11. ©2010 AACR.
Expression of LIGHT/TNFSF14 Combined with Vaccination against Human Papillomavirus Type 16 E7 Induces Significant Tumor Regression
Authors: Kanodia Shreya , Da Silva Diane M. , Karamanukyan Tigran , Bogaert Lies , Fu Yang-Xin , Kast W. Martin
Published: May 2010

LIGHT, a ligand for the lymphotoxin-β receptor, establishes lymphoid-like tissues inside tumor sites and recruits naïve T cells into the tumor. However, whether these infiltrating T cells are specific for tumor antigens is not known. We hypothesized that therapy with LIGHT can expand functional tumor-specific CD8+ T cells that can be boosted using HPV16E6E7-Venezuelan equine encephalitis virus replicon particles (HPV16-VRP) and that this combined therapy can eradicate human papillomavirus 16 (HPV16)–induced tumors. Our data show that forced expression of LIGHT in tumors results in an increase in expression of IFNγ and chemoattractant cytokines such as interleukin-1a, MIG, and macrophage inflammatory protein-2 within the tumor and that this tumor microenvironment correlates with an increase in frequency of tumor-infiltrating CD8+ T cells. Forced expression of LIGHT also results in the expansion of functional T cells that recognize multiple tumor antigens, including HPV16 E7, and these T cells prevent the outgrowth of tumors on secondary challenge. Subsequent boosting of E7-specific T cells by vaccination with HPV16-VRP significantly increases their frequency in both the periphery and the tumor and leads to the eradication of large well-established tumors, for which either treatment alone is not successful. These data establish the safety of Ad-LIGHT as a therapeutic intervention in preclinical studies and suggest that patients with HPV16+ tumors may benefit from combined immunotherapy with LIGHT and antigen-specific vaccination. Cancer Res; 70(10); 3955–64. ©2010 AACR.
Autocrine Induction of Invasive and Metastatic Phenotypes by the MIF-CXCR4 Axis in Drug-Resistant Human Colon Cancer Cells
Authors: Dessein Anne-Frédérique , Stechly Laurence , Jonckheere Nicolas , Dumont Patrick , Monté Didier , Leteurtre Emmanuelle , Truant Stéphanie , Pruvot François-René , Figeac Martin , Hebbar Mohamed , Lecellier Charles-Henri , Lesuffleur Thécla , Dessein Rodrigue , Grard Georges , Dejonghe Marie-José , de Launoit Yvan , Furuichi Yasuhiro , Prévost Grégoire , Porchet Nicole , Gespach Christian , Huet Guillemette
Published: May 2010

Metastasis and drug resistance are major problems in cancer chemotherapy. The purpose of this work was to analyze the molecular mechanisms underlying the invasive potential of drug-resistant colon carcinoma cells. Cellular models included the parental HT-29 cell line and its drug-resistant derivatives selected after chronic treatment with either 5-fluorouracil, methotrexate, doxorubicin, or oxaliplatin. Drug-resistant invasive cells were compared with noninvasive cells using cDNA microarray, quantitative reverse transcription-PCR, flow cytometry, immunoblots, and ELISA. Functional and cellular signaling analyses were undertaken using pharmacologic inhibitors, function-blocking antibodies, and silencing by retrovirus-mediated RNA interference. 5-Fluorouracil– and methotrexate-resistant HT-29 cells expressing an invasive phenotype in collagen type I and a metastatic behavior in immunodeficient mice exhibited high expression of the chemokine receptor CXCR4. Macrophage migration-inhibitory factor (MIF) was identified as the critical autocrine CXCR4 ligand promoting invasion in drug-resistant colon carcinoma HT-29 cells. Silencing of CXCR4 and impairing the MIF-CXCR4 signaling pathways by ISO-1, pAb FL-115, AMD-3100, monoclonal antibody 12G5, and BIM-46187 abolished this aggressive phenotype. Induction of CXCR4 was associated with the upregulation of two genes encoding transcription factors previously shown to control CXCR4 expression (HIF-2α and ASCL2) and maintenance of intestinal stem cells (ASCL2). Enhanced CXCR4 expression was detected in liver metastases resected from patients with colon cancer treated by the standard FOLFOX regimen. Combination therapies targeting the CXCR4-MIF axis could potentially counteract the emergence of the invasive metastatic behavior in clonal derivatives of drug-resistant colon cancer cells. Cancer Res; 70(11); 4644–54. ©2010 AACR.