bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal Conductivity Laboratory Studies of Some Mackenzie Highway Soils
Authors: Penner E. , Johnston G. H. , Goodrich L. E.
Published: July 2008

Thermal conductivities were determined for 10 fine-grained soils obtained from potential borrow pit areas along the proposed route of the Mackenzie Highway, N.W.T., and from the nearly completed section of the Mackenzie Highway, just south of Inuvik. The moisture contents and densities of the test specimens were based on the standard Proctor density curves. The measurements were made by the transient heat-flow method using a line heat source. The values were in good agreement with Kersten's data obtained by the steady-state heat flow method.Grain-size, mineralogical analyses of the clay-size fraction, Atterberg limits, and standard Proctor density determinations are given for all 10 soils.
On the Role of Chemistry in the Development and Behavior of the Sensitive Marine Clays of Canada and Scandinavia
Authors: Torrance J. Kenneth
Published: July 2008

The Scandinavian and Canadian experiences are reviewed and analyzed in the light of recent experiments involving the effects of added salts on the remolded shear strength and the liquid limits of two Ottawa area clays, both of which had low porewater salinity in their natural state. The response was similar to that observed in the Scandinavian marine clays where the sensitivity decreases as the salinity increases. It is concluded that the similarities relating to the influence of chemical factors are greater than previous interpretations have indicated. The precise relationship between porewater salinity and sensitivity in Leda clay appears to be unique to each sample and a broad geographic relationship should not be expected. Even short range similarities may be obscured by the generally low salinities of the Canadian marine clays and the great variability in other factors, such as texture and degree of cementation, which also affect the sensitivity.
Bulkhead Pressures Due to Cemented Hydraulic Mine Backfills
Authors: Mitchell R. J. , Smith J. D. , Libby D. J.
Published: July 2008

Hydraulically placed cemented tailings, with a 30:1 tailings–cement ratio, have been used to backfill large blast-hole stopes at Fox Mine in Northern Manitoba. Heavily reinforced concrete bulkhead supports were provided to prevent intrusion of hydraulic fill materials into the mine drifts. Instrumentation was installed through several of these bulkheads to measure horizontal stresses on the bulkheads and pore water pressures at several points in the fill. Fill quantities, fill levels, and water balance were monitored in conjunction with the instrumentation. Measured bulkhead stresses were much less than anticipated due, apparently, to the effects of arching and cementation. Timber bulkheads, designed on the field measurements, were found to perform satisfactorily in subsequent stope pours. Backfill drainage appeared to follow the general predictions made from laboratory permeability tests on control cylinders.
Concrete Deterioration and Floor Heave Due to Biogeochemical Weathering of Underlying Shale
Authors: Grattan-Bellew P. E. , Eden W. J.
Published: July 2008

When the basement floor of a church in the New Edinburgh area of Ottawa heaved, it was discovered that the concrete under the floor had been reduced to a mushy consistency due to attack by sulfate solution formed by the oxidation of pyrite in the underlying shale. Gypsum was the main product in the weathered zone of the shale. It is shown that heaving resulted from the growth of gypsum crystals between the lamellae in the shale. Jarosite, which is formed by a series of oxidation reactions from pyrite, was also found in the weathered shale. Some oxidation reactions occur only in the presence of sulfur bacteria. The cementitious portion of the concrete was leached out by acid, leaving a weak porous material. The importance of safeguarding concrete in contact with potentially expansive shales from sulfate attack is emphasized.
The Little Smoky Landslide
Authors: Thomson S. , Hayley D. W.
Published: July 2008

The west abutment of the Little Smoky River bridge in central Alberta showed evidence of movement toward the river. Subsequent investigations revealed that the landslide on which the bridge was built was moving slowly. The Little Smoky River occupies a broad preglacial valley eroded in Upper Cretaceous clay shales and is re-excavating tills deposited during glaciation. The site was instrumented with tiltmeters to define the failure planes. Soil strength parameters were determined on samples obtained from boreholes. Analysis revealed that the failure mechanism consisted of a series of blocks each acting as a separate entity but all merging to a common lower shear zone. The key to understanding the failure is the failure of the individual blocks progressively from the toe to the scarp. The slow movement allows the bridge to be kept in service. Since the first block is subject to river erosion, its stabilization would be a step in stabilizing the slope.
Response Testing of Piezometers in Fractured Porous Media
Authors: Schwartz Franklin W.
Published: July 2008

Conventional methods of piezometer response testing are unsuitable for analyzing observed data from three piezometers placed in fractured coal and siltstone units. However, these responses correspond closely to the results of pressure tests in fractured limestones (Pollard). Following an extended form of the Pollard analysis, the fracture porosity within fractured coal units is calculated to comprise approximately 3.7% of the total porosity. In the deeper siltstone unit, the fracture porosity makes up only 0.5% of the total porosity. The application of basic time lag principles (Hvorslev) to separate segments of the Pollard plot makes it possible to determine the hydraulic conductivity of the matrix and fracture systems. The hydraulic conductivity of the fracture system is calculated to be 40 to 250 times higher than the matrix.
Analysis of the Pore Pressure Changes Following the Excavation of a Slope
Authors: Eigenbrod Kurt D.
Published: July 2008

In a numerical analysis the pore pressure changes due to excavation of a slope and the subsequent dissipation of excess pore pressures were calculated. The analytical results of the pore pressure changes due to unloading of a slope agree reasonably well with pore pressure measurements in comparable embankments. This suggests that pore pressures immediately after slope excavation can be predicted analytically in homogeneous materials.The results of an analysis dealing with the dissipation of excess pore pressures due to unloading can also be substantiated by field evidence; however, only few comparable field data are available. For many slopes it can be noted that the time for full dissipation is of the same order of magnitude as the time between excavation and failure. This suggests that many failures might be caused by the delayed equalization of pore pressures.
Prediction of Pile Performance in Permafrost Under Lateral Load
Authors: Rowley R. K. , Watson G. H. , Ladanyi B.
Published: July 2008

In 1971 lateral pile tests were performed at Inuvik, N.W.T. to determine design values in creep for timber and steel pipe piles. Formulation of a theoretical method for prediction of pile load capacity from basic permafrost creep parameters was a part of this program.In 1972 pressuremeter creep tests were performed at the same site so that test pile performance could be predicted independently and compared with measured results. The pressuremeter tests made and the creep parameter values obtained, the predicted pile performance curves and the comparisons with actual test data are presented in this paper.A Menard pressuremeter was used to determine permafrost creep parameters at an average ground temperature of 29.2 °F (−1.6 °C). Values for the representative creep modulus and exponents for this soil were derived from the test data. These were used for calculating pressure–deflection curves and subgrade reaction moduli for the laterally loaded piles.To demonstrate the applicability of the theory, the subgrade reaction moduli derived from the pressuremeter tests were compared with those deduced directly from the pile load tests. A reasonable agreement was found with the subgrade reaction moduli values obtained for the timber piles. However, the steel pipe piles responded as though the modulus was much higher.The confirmation field tests were made at a site having ice-rich permafrost whose behavior approaches that of pure ice. To apply the basic theory generally, additional field confirmation tests would be needed, for example, in ice-poor permafrost and covering much longer periods of time.
Centrifugal model tests of the Lodalen landslide
Authors: Lyndon A. , Schofield A. N.
Published: July 2008

The slide which occurred at Lodalen, Oslo in 1954 was used to compare the behaviour of soil models tested in a centrifuge with a well-documented prototype event.The paper describes the centrifugal testing of three models prepared from block samples in which an attempt was made to simulate the stress history of the site. The results of these model tests are presented as an analogous prototype by the application of the simple scaling laws, which when compared with the actual prototype were found to present a realistic facsimile of the landslide.
Janbu, Bjerrum and Kjaernsli's chart reinterpreted
Authors: Christian John T. , David Carrier III W.
Published: July 2008

The chart developed by Janbu, Bjerrum and Kjaernsli for estimating average elastic settlement of embedded foundations is examined to determine whether improvements can be made in the light of modern capabilities for stress analysis. The parameter describing the effect of a finite layer can be evaluated more accurately from recent results such as those of Giroud. The parameter describing the effect of embedment was originally taken precisely from Fox's work, but finite element analyses indicate that Fox's correction substantially overestimates the effect of embedment. A better estimate can be made by using Burland's correction or, more simply, by ignoring the effects of embedment altogether.
Origine de la préconsolidation des argiles du Saguenay, Québec
Authors: Bouchard R. , Dion D. J. , Tavenas F.
Published: July 2008

The clays of Eastern Canada, and in particular the Saint-Jean-Vianney clay in the Saguenay region, have often been described as clays with a preconsolidation due partly to cementation. In order to check this assumption, the geological history and the geomorphology of the Saguenay region have been analyzed. Further to the evidence of significant erosion, available geotechnical data in the form of variations of water content, undrained shear strength, and preconsolidation pressure have been analyzed to determine the elevation of the original ground surface in the hypothesis of a preconsolidation resulting from deposition and erosion. The results of this analysis are in good agreement with the geological and geomorphological data and they suggest that cementation has had a negligible effect on the preconsolidation of the Saguenay clays. A regional map of preconsolidation pressures is also presented. Keywords: clay, preconsolidation, geomorphology, erosion, shear strength. [Journal translation]
The mechanical behavior of Anvil Points oil shale at elevated temperatures and confining pressures
Authors: Zeuch David H.
Published: July 2008

Twenty-one constant-strain-rate compression tests have been performed on 80 mL/kg (20 gallons/ton) Anvil Points oil shale at elevated temperatures (50–200 °C) and confining pressures (0.5–40 MPa). The strength of oil shale increases approximately linearly with confining pressure and decreases nonlinearly with temperature. Ductility is greatly enhanced by the application of confining pressure. Elevated temperatures have little influence on ductility at low confining pressures; however, temperature exerts a progressively more pronounced influence on ductility with increasing confining pressure. A purely empirical failure law, incorporating the effects of temperature and confining pressure, has been fitted to the data. The failure law is in good agreement with the results of other studies on the compressive strength of oil shale. Keywords: oil shale, strength–temperature–pressure behaviour, rock mechanics, kerogen.
Some experimental studies concerning the contact stresses beneath interfering rigid strip foundations resting on a granular stratum
Authors: Selvadurai A. P. S. , Rabbaa S. A. A.
Published: July 2008

This paper presents an experimental study of the contact stress distribution beneath two interfering rigid strip foundations resting in frictionless contact with a layer of dense sand underlain by a smooth rigid base. It is found that the interference between the two foundations has a significant influence on the contact stress distribution. In the absence of interference, the contact stress distribution beneath a single foundation exhibits a symmetrical shape. As the spacing between the foundations diminishes the contact stress distribution exhibits an asymmetrical shape. Keywords: contact stresses, foundation interference, plane strain tests, experimental studies.
Settlement of a strip footing on a confined clay layer
Authors: Taylor Brian B. , Matyas Elmer L.
Published: July 2008

A procedure is described that permits an estimation of either consolidation or immediate settlements of a uniformly loaded, flexible strip footing founded below the ground surface. The soil above the base of the footing is sand, and the soil below the base consists of clay, which extends to a finite depth. The procedure is based on a solution of Kelvin's equations for a line load acting within an infinite solid. Charts are presented which permit an estimate of settlement for various compression moduli, Poisson's ratio, and clay thickness.The proposed method predicts consolidation settlements that are generally slightly greater than those predicted from Boussinesq theory. Consolidation settlements increase as Poisson's ratio increases. Immediate settlements are slightly greater than those reported previously. Keywords: consolidation, elasticity, footings, plane strain, settlement analysis, stress distribution.
An analysis of three-dimensional ground movements: the Thunder Bay tunnel
Authors: Lee K. M. , Rowe R. K.
Published: July 2008

A three-dimensional (3D) elastoplastic finite-element analysis, which is capable of simulating the advance of a tunnelling shield and the associated ground losses resulting from the tunnelling process, is used to calculate the deformations caused by the excavation of the Thunder Bay sewer tunnel. The soil parameters adopted in the analysis were based on the results determined from stress-dependent triaxial tests. The results of this analysis are compared with the measured soil displacements. Reasonable agreement between the calculated and observed 3D settlement distribution and horizontal displacements at different distances from the tunnel face is reported. This overall agreement for displacements under 3D conditions suggests that the method of analysis may be applicable to design problems involving tunnelling in soft clays similar to that at the Thunder Bay sewer tunnel provided that the soil parameters are reliably determined. Key words: tunnelling, three-dimensional analysis, finite element, elastoplastic displacements, ground deformations, Thunder Bay tunnel.
The September 5, 1987, landslide on the La Grande River, James Bay, Quebec, Canada
Authors: Lefebvre Guy , Rosenberg Peter , Paquette Jean , Lavallée J. G.
Published: July 2008

The September 5, 1987, landslide at kilometre 82.5 on La Grande River affected a slope about 60 m high inclined at about 35°. The site had been identified as presenting high risks of a major landslide and had been under observation for several years. The conditions existing before the landslide are relatively well documented from a deep boring put down in 1975 at the slide location and from prior observations and photographs of the river bank erosion. The overburden deposit, sand at the ground surface changing to a silty clay at depth, was normally consolidated but affected by a strong underdrainage. Stability analyses confirm the strong underdrainage deduced from the 1975 piezometric reading. The slide retrogressed 290 m from the river on a surface inclined at 6°. The location of the retrogression surface appears related to the undrained shear strength profile. Key words: landslide, earthflow, sensitive clay, groundwater, river erosion, slope stability.
Modelling of two-dimensional contaminant migration in a layered and fractured zone beneath landfills
Authors: Rowe R. Kerry , Booker John R.
Published: July 2008

A new two-dimensional finite layer formulation that allows consideration of both vertical and horizontal contaminant migration in systems that may consist of both fractured and unfractured layers is described. Consideration is given to contaminant migration from typical municipal and nonhazardous waste disposal sites. The migration of concentrated dense nonaqueous phase contaminant, which involves additional transport mechanisms, is not considered in this paper. The use of the theory is illustrated with respect to a number of hypothetical cases. The results indicate that even relatively widely spaced small fractures can have a significant effect on potential impact on groundwater quality in an underlying aquifer. It is also shown that when dealing with relatively impermeable tills, impact on an underlying aquifer may not occur until after the landfill leachate is at a low strength; however, the impact may be quite significant and may last for hundreds of years. Consideration is given to the implication of regulatory policies that specify the maximum impact that can ever be permitted and those that simply specify that there be no impact for a specified (e.g., 100 year) period. It is shown that landfills that meet the requirements of no impact within the first 100 years may subsequently have a significant (unacceptable) impact on groundwater quality. Key words: clay, fractures, contaminant impact, analysis, design, diffusion.
Model pile testing in carbonate sediments of the Red Sea
Authors: Baghdadi Zaki A. , Ghazali Fouad M. , Khan Ahmed M.
Published: July 2008

This paper presents the results of an experimental program of model piles in carbonate soil from the Red Sea. Direct and triaxial shear tests of the soil indicated very high effective angles of friction. These angles were greatly affected by confining pressures and relative densities. Results of model pile tests with and without applied surcharge pressures showed early peak frictional resistances for different relative densities. The peaks were stronger in the former case and followed by strain softening down to "stable" residual values. These residual values were found to be comparable with limiting values of friction predicted on the basis of limiting compressibility indices. Also, it was noticed that at the beginning of penetration, most of the applied load was taken by end bearing, but frictional share increased with further penetration until it took more than 50% of the load. Calculated values of the lateral soil pressure coefficient, Ks, showed a continuous decrease with penetration and it stabilized at deeper depths. Statistical correlations were found to relate Ks with the L/D ratio and surcharge pressure. Key words: ocean soil, sand, shear strength, pile, model test, bearing capacity, friction, uplift, active and passive earth pressures.
On the yield stress of geotechnical materials from the slump test
Authors: Rajani B. , Morgenstern N.
Published: July 2008

There exists an important class of materials, e.g., debris, volcanic lava, sludges, and remoulded sensitive clays, that are known to behave like a Bingham fluid. One of the important properties of a Bingham fluid is the so-called yield stress, and it is usually determined using a coaxial viscometer apparatus. It would be impractical and cumbersome to use this apparatus for many of the materials referred to earlier, and we propose here to examine the use of the slump test. The slump test is used in the concrete industry to evaluate workability and consistency. A statical model is developed to explain the deformation mechanism, and it permits the determination of yield stress. The validity of the statical model is verified using published data on mortar and our own data on Devon silt. The yield stress obtained with the slump test is also compared with the undrained shear strength obtained using the fall cone test. Good agreement is found between the two values. Key words: Bingham fluid, yield stress, slump test, Devon silt.
Yield stress measurement by a penetration method
Authors: Tan Thiam-Soon , Goh Teik-Cheong , Karunaratne G. P. , Inoue Toshiyuki , Lee Seng-Lip
Published: July 2008

Shear strength is an important parameter in the study of extremely soft clays or slurries. Measurement of shear strength less than 0.5 kPa is limited to a few methods such as the rotary viscometer and the Swedish fall cone; the former is suitable for slurries and the latter for soft clay. An alternative method that relies on the incremental vertical penetration of a thin plate under an incremental load to directly obtain the shear strength of extremely soft clays is investigated here. The effect of the plate material is shown to be negligible. The shear strength determined using this method was then compared with those obtained from the rotary viscometer and the Swedish fall cone. Good agreement is achieved in the ranges where they overlapped, thus confirming the validity of this method. The attractiveness of this method is its simplicity. Moreover, it is suitable for measurement of shear strengths below the Swedish fall cone range. Key words: thin plate, penetration, slurry, yield stress.
Effect of seafloor instability on offshore pile foundations
Authors: Lee C. Y. , Poulos H. G. , Hull T. S.
Published: July 2008

This paper employs a modified nonlinear boundary element approach to analyze the response of offshore piles subjected to external soil movements arising from submarine slides. Theoretical solutions for a realistic hypothetical offshore pile computed by the approach are presented and discussed. The analysis is then used to analyze the behaviour of two full-scale offshore piles in submarine slide areas, and reasonable agreement is found between observed and theoretical behaviour. Key words: seafloor instability, submarine slides, offshore piles, theoretical solutions, field tests.
A framework for simulation of surrounding vehicles in driving simulators
Authors: Olstam Johan Janson , Lundgren Jan , Adlers Mikael , Matstoms Pontus
Published: July 2008

This article describes a framework for generation and simulation of surrounding vehicles in a driving simulator. The proposed framework generates a traffic stream, corresponding to a given target flow and simulates realistic interactions between vehicles. The framework is based on an approach in which only a limited area around the driving simulator vehicle is simulated. This closest neighborhood is divided into one inner area and two outer areas. Vehicles in the inner area are simulated according to a microscopic simulation model including advanced submodels for driving behavior while vehicles in the outer areas are updated according to a less time-consuming mesoscopic simulation model. The presented work includes a new framework for generating and simulating vehicles within a moving area. It also includes the development of an enhanced model for overtakings and a simple mesoscopic traffic model. The framework has been validated on the number of vehicles that catch up with the driving simulator vehicle and vice versa. The agreement is good for active and passive catch-ups on rural roads and for passive catch-ups on freeways, but less good for active catch-ups on freeways. The reason for this seems to be deficiencies in the utilized lane-changing model. It has been verified that the framework is able to achieve the target flow and that there is a gain in computational time of using the outer areas. The framework has also been tested within the VTI Driving simulator III.
Algorithm 877
Authors: Kodama Masao
Published: July 2008

The algorithm presented provides a package of subroutines for calculating the cylindrical functions
J
ν
(
x
),
N
ν
(
x
),
H
ν
(1)
(
x
),
H
ν
(2)
(
x
) where the order
ν
is complex and the real argument
x
is nonnegative. The algorithm is written in Fortran 95 and calculates the functions using single, double, or quadruple precision according to the value of a parameter defined in the algorithm. The methods of calculating the functions are based on a series expansion, Debye's asymptotic expansions, Olver's asymptotic expansions, and recurrence methods (Miller's algorithms). The relative errors of the functional values computed by this algorithm using double precision are less than 2.4×10
 − 13
in the region 0 ≤ Re
ν
 ≤ 64, 0 ≤ Im
ν
 ≤ 63, 0.024 ≤ 
x
 ≤ 97.
Search, sort, pagination, association and (other) CRUD
Authors: Serfass Doug , Thiparthi Kalyan S. , Bayrak Coskun
Published: July 2008

Web applications have many more model objects exposed on the backend, or admin side, than they do on the front, or public side. Coding interfaces for all those models is redundant and a waste of resources when all that is needed is Search, Sort, Pagination, (support for) Association and CRUD. Implementing these interfaces can often require more programming time than the public side of an application. We will analyze an application that was developed using Ruby on Rails (or Rails) [1] and ActiveScaffold [2]. We will compare a subset of the ActiveScaffold portion of this application with an example created using Java and MyFaces Tomahawk [3]. ActiveScaffold and MyFaces Tomahawk are open source software (OSS). Our results will show that ActiveScaffold has a greater number of features and is more reusable than MyFaces Tomahawk. This information is useful to web developers responsible for creating the admin interfaces of web applications.
Managing software defects
Authors: Henderson Craig
Published: July 2008

This paper describes a mechanism for presenting software defect metrics to aid analysis. A graphical representation of the history of software builds is presented, that records software build quality in a way that cannot be displayed in a single numerical table, and is visually more appealing and more easily digestible than a series of related tables. The radial analysis charts can be used to represent derivative information in a two-dimensional form and is demonstrated with practical examples of Defect Analysis and Root Cause Analysis.
ACM TOSEM
Authors: Notkin David
Published: July 2008

It's been a while since I've written a column on TOSEM. One reason for this is, of course, that I simply haven't gotten to it. The other reason for this is because of you: I've had few, if any, questions or comments about TOSEM from the SEN readership. If this was because everything at TOSEM was perfect and we were so transparent that you knew everything we knew, I'd be thrilled. But that's just never the case. So, please send me email with your comments, questions, concerns, TOSEM-related jokes, or whatever.
Leadership and management in software architecture (LMSA'08)
Authors: Bass Len , Berenbach Brian
Published: July 2008

This is a report of the Leadership and Management in Software Architecture workshop that took place at ICSE 2008. The workshop focused on the non-technical aspects of software architecture. In particular, it focused on the skills that a software architect should have as well as the type of support an organization should provide for the architect.
A theoretical framework for knowledge transfer in process redesign
Authors: Fadel Kelly J. , Brown Susan A. , Tanniru Mohan
Published: July 2008

Business process redesign has become commonplace in today's organizations. A frequently overlooked consequence of process redesign is the learning barriers it creates for individuals who have to change the way they perform their work tasks. One way to overcome these barriers is through a process of knowledge transfer, wherein individuals apply their knowledge of existing work tasks to learn new work tasks. While transfer may facilitate learning through reuse of existing knowledge, it may also impede learning. Drawing on theories of task knowledge and analogical learning, this paper presents a task script framework and associated research propositions for knowledge transfer in process redesign. The framework is illustrated in the context of a real-world example, and implications for research and practice are discussed.
An empirical investigation of virtual Interaction in supporting learning
Authors: Cao Jinwei , Crews Janna M. , Lin Ming , Burgoon Judee K. , Nunamaker Jay F.
Published: July 2008

This research investigates "virtual interaction," a special type of interaction between a learner and a rich media representation of an instructor. Guided by the Technology Mediated Learning (TML) research framework, the research investigates the impacts of different types of virtual interaction on the effectiveness of online learning based on a review of multiple learning theories and technologies, including theories about interactions in learning, types of knowledge, and learning outcomes, as well as technologies about video-based question answering (QA). An exploratory research study, in the form of a field experiment, has been conducted to explain the relationships among the types of interaction, types of knowledge being learned, and learning outcomes. Findings from this study indicate that QA-based virtual interaction increases learner satisfaction with interaction in learning conceptual knowledge; however, the influence of virtual interaction on actual learning performance is limited.
Catch Bonds in Adhesion
Authors: Thomas Wendy
Published: July 2008

One of the most exciting discoveries in biological adhesion is the recent and counter-intuitive observation that the lifetimes of some biological adhesive bonds, called catch bonds, are enhanced by tensile mechanical force. At least two types of adhesive proteins have been shown to form catch bonds—blood proteins called selectins and a bacterial protein called FimH. Both mediate shear-enhanced adhesion, in which cells bind more strongly at high shear than at low shear. Single-molecule experiments and cell-free assays have now clearly demonstrated that catch bonds exist and mediate shear-enhanced adhesion. However, the mechanics of cellular organelles also contribute to shear-enhanced adhesion by modulating the force applied to catch bonds. This review examines how individual catch bond behavior contributes to shear-enhanced cellular adhesion for the two best-understood examples. The lessons from these systems offer design principles for understanding other types of shear-enhanced adhesion and for engineering nanostructured force-dependent adhesives out of catch bonds.
A Sensitive and Rapid Assay for Investigating Vertical Transmission of Hepatitis B Virus via Male Germ Line Using EGFP Vector as Reporter
Authors: Ahmed Mohamed Morsi M. , Huang Tian-Hua , Xie Qing-Dong
Published: July 2008

Hepatitis B virus (HBV) constitutes a serious menace to man. DNA recombination and sequencing, interspecific in vitro fertilization, single‐embryo PCR and RT‐PCR were employed to establish a sensitive and rapid assay for exploring the vertical transmission of viruses via male germ line. Plasmid pIRES2‐EGFP‐HBs which expressed enhanced green fluorescent protein as reporter for the expression of hepatitis B virus S gene was successfully constructed and confirmed by PCR, EcoR I and Sal I digestion, and DNA sequencing. After exposure to the plasmid, human spermatozoa were used to fertilize with zona‐free hamster ova. Two‐cell embryos were collected and classified into group A with green fluorescence and group B without green fluorescence under fluorescence microscope. The results showed that HBs DNA positive bands were detected in the embryos with green fluorescence (PCR and RT‐PCR) and positive control (PCR) indicating expression of pIRES2‐EGFP‐HBs, and not observed in the embryos without green fluorescence and negative controls (PCR and RT‐PCR) indicating no pIRES2‐EGFP‐HBs in the cells. The advantages and application foreground of this assay for study on vertical transmission of viruses such as HCV, HIV, HPV, and SARS via germ line were discussed.
Comparative Analysis of Power‐Law Fin‐Type Problems Using Variational Iteration Method and Finite Element Method
Authors: Atay Mehmet Tarık , Coşkun Safa Bozkurt
Published: July 2008

Variational iteration method is applied to examine the temperature
distribution within a single fin with a one‐dimensional steady‐state nonlinear heat conduction
equation. Variation of temperature due to different levels of nonlinearities is analyzed. The
results obtained by means of variational iteration method are compared with the results obtained
from finite element method. A fourth iteration variational iteration solution is used in all cases
considered. An error analysis is also conducted to evaluate the performance of proposed solution
technique. The results have shown that variational iteration method is a powerful solution
technique in the analysis of power‐law fin‐type problems.
Linking Cellular Mechanisms to Behavior: Entorhinal Persistent Spiking and Membrane Potential Oscillations May Underlie Path Integration, Grid Cell Firing, and Episodic Memory
Authors: Hasselmo Michael E. , Brandon Mark P.
Published: July 2008

The entorhinal cortex plays an important role in spatial memory and episodic memory functions. These functions may result from cellular mechanisms for integration of the afferent input to entorhinal cortex. This article reviews physiological data on persistent spiking and membrane potential oscillations in entorhinal cortex then presents models showing how both these cellular mechanisms could contribute to properties observed during unit recording, including grid cell firing, and how they could underlie behavioural functions including path integration. The interaction of oscillations and persistent firing could contribute to encoding and retrieval of trajectories through space and time as a mechanism relevant to episodic memory.
Proteomic Approaches in Understanding Action Mechanisms of
Metal-Based Anticancer Drugs
Authors: Wang Ying , Chiu Jen-Fu
Published: July 2008

Medicinal inorganic chemistry has been stimulating largely by the success of the anticancer drug, cisplatin. Various metal complexes are currently used as therapeutic agents (e.g., Pt, Au, and Ru) in the treatment of malignant diseases, including several types of cancers. Understanding the mechanism of action of these metal-based drugs is for the design of more effective drugs. Proteomic approaches combined with other biochemical methods can provide comprehensive understanding of responses that are involved in metal-based anticancer drugs-induced cell death, including insights into cytotoxic effects of metal-based anticancer drugs, correlation of protein alterations to drug targets, and prediction of drug resistance and toxicity. This information, when coupled with clinical data, can provide rational basses for the future design and modification of present used metal-based anticancer drugs.
Role of Nonlinear Atmospheric Response to SST on the Asymmetric Transition Process of ENSO
Authors: Ohba Masamichi , Ueda Hiroaki
Published: July 2008

Physical processes that are responsible for the asymmetric transition processes between El Niño and La Niña events are investigated by using observational data and physical models to examine the nonlinear atmospheric response to SST. The air–sea coupled system of ENSO is able to remain in a weak, cold event for up to 2 yr, while the system of a relatively warm event turns into a cold phase. Through analysis of the oceanic observational data, it is found that there is a strong difference in thermocline variations in relation to surface zonal wind anomalies in the equatorial Pacific (EP) during the mature-to-decaying phase of ENSO. The atmospheric response for the warm phase of ENSO causes a rapid reduction of the EP westerlies in boreal winter, which play a role in hastening the following ENSO transition through the generation of upwelling oceanic Kelvin waves. However, the anomalous EP easterlies in the cold phase persist to the subsequent spring, which tends to counteract the turnabout from the cold to warm phase of ENSO.

A suite of idealized atmospheric general circulation model (AGCM) experiments are performed by imposing two different ENSO-related SST anomalies, which have equal amplitudes but opposite signs. The nonlinear climate response in the AGCM is found at the mature-to-decaying phase of ENSO that closely resembles the observations, including a zonal and meridional shift in the equatorial positions of the atmospheric wind. By using a simple ocean model, it is determined that the asymmetric responses of the equatorial zonal wind result in different recovery times of the thermocline in the eastern Pacific. Thus, the differences in transition processes between the warm and cold ENSO event are fundamentally due to the nonlinear atmospheric response to SST, which originates from the distribution of climatological SST and its seasonal changes. By including the asymmetric wind responses the intermediate air–sea coupled model herein demonstrates that the essential elements of the redevelopment of La Niña arise from the nonlinear atmospheric response to SST anomalies.
Patterns of Victimization and Feelings of Safety Inside Prison: The Experience of Male and Female Inmates
Authors: Wolff Nancy , Jing Shi
Published: July 2008

Little is known about the patterns of sexual victimization inside prisons and their relationship to inmates’ feelings of safety. This study examined patterns of sexual victimization with and without co-occurring physical victimization and feelings of safety as reported by 6,964 male and 564 female inmates. Respondents completed a computerized survey with questions about type of victimization (sexual/physical) and source of victimization (inmate/staff). Compared to sexual assault, inappropriate sexual touching was more common, especially among female inmates (22% versus 4%), whereas sexual assault was relatively less common for male and female inmates (< 2%). Sexual victimization often involved one to three types of sexually inappropriately behavior. Victimization perpetrated by staff was more frequently reported by male inmates. Most inmates, independent of gender and sexual victimization, reported feeling safe inside prison. Inmates who felt the most unsafe reported sexual victimization by staff or concurrent sexual and physical victimization ( n = 150).
The MusicStart Project: an evaluation of the impact of a training programme to enhance the role of music and singing in educational settings for children aged three to five years
Authors: Mackenzie Karen , Clift Stephen
Published: July 2008

This article evaluates the impact of an innovative early years music project developed on the Isle of Wight, UK, which aimed to enhance the role of music-making in educational settings for three- to five-year-old children. The MusicStart Project designed an original model for training practitioners working in such settings to increase their confidence and skills in making music with their pupils. A variety of instruments were used to collect feedback and all participating practitioners ( N = 120) were asked to complete a questionnaire following the training and a 53 percent response rate was achieved. The feedback indicated that the majority of practitioners found it useful and were inspired to put new ideas into practice. About a quarter of practitioners indicated that they were already making music with confidence and very few felt that the training had not influenced their future practice. The practitioners and MusicStart leaders identified some challenges to sustaining the levels of music-making that followed immediately after the training, most significantly: opportunities to cascade new ideas with colleagues; conflicts with other professional demands; and the time needed to enable practitioners to establish new skills and ideas.
The effects of gesture use on young children's pitch accuracy for singing tonal patterns
Authors: Liao Mei-Ying
Published: July 2008

The main purpose of this study was to examine the effects of gesture use on young children's singing with regard to improving pitch accuracy. The second purpose was to examine the differences in gesture use among boys and girls and different melodic motions. Eighty Taiwanese young children, five to six years old, participated in this experiment. The children were asked to sing six tonal patterns with and without gestures, which subsequently were evaluated by three professional music teachers. The results showed that gesture use had immediate positive effects for young children in aiding their pitch accuracy. The effect of gestures for girls was greater than for boys. However, the level of gesture effects in melodic motions was different. Gesture had a greater effect for repetition, ascending patterns and large leaps. Sweeping and opening—closing arm gestures especially appeared to work very successfully. This suggests that gestures provided a kinesthetic sense of motion, which can be an effective tool in aiding singing.
Acute Achilles Tendon Rupture
Authors: Metz Roderick , Verleisdonk Egbert-Jan M. M. , van der Heijden Geert J.-M.-G. , Clevers Geert-Jan , Hammacher Erik R. , Verhofstad Michiel H. J. , van der Werken Christiaan
Published: July 2008

Background

Surgical repair of acute Achilles tendon ruptures is considered superior to nonoperative treatment, but complications other than rerupture range up to 34%. Nonoperative treatment by functional bracing seems a promising alternative.

Hypothesis

Nonoperative treatment of acute Achilles tendon rupture with functional bracing reduces the number of complications compared with surgical treatment with a minimally invasive technique.

Study Design

Randomized controlled clinical trial; Level of evidence, 2.

Method

Using concealed random allocation, 83 patients with acute Achilles tendon rupture were assigned to nonoperative treatment by functional bracing or minimally invasive surgical treatment followed by tape bandage. Patients were allowed full weightbearing, and follow-up was 1 year.

Results

Complications risk other than rerupture by intention-to-treat basis was 9 in 42 patients (21 %) for surgical treatment and 15 in 41 patients (36%) for nonoperative treatment (risk ratio, 0.59; 95% confidence interval, 0.29-1.19). Reruptures risk was 5 in 41 patients after nonoperative treatment and 3 in 42 patients for surgical treatment (risk ratio, 0.59; 95% confidence interval, 0.15-2.29). The mean time to work was 59 days (SD, 82) after surgical treatment and 108 days (SD, 115) after nonoperative treatment (difference, 49 days; 95% confidence interval, 4-94; P < .05). The difference between treatments for return to sports (risk ratio, 0.55; 95% confidence interval, 0.23-1.29), pain, and treatment satisfaction did not reach statistical significance.

Conclusion

There appears to be a clinically important difference in the risk of complications between minimally invasive surgical treatment and nonoperative treatment for acute Achilles tendon ruptures, but this was not statistically significant.
Profound Biotinidase Deficiency in a Child With Predominantly Spinal Cord Disease
Authors: Chedrawi Aziza K. , Ali Ayman , Al Hassnan Zuhair N. , Faiyaz-Ul-Haque Muhammad , Wolf Barry
Published: July 2008

Biotinidase deficiency is an autosomal recessively inherited disorder that manifests during childhood with various cutaneous and neurological symptoms particularly seizures, hypotonia, and developmental delay. Spinal cord disease has been reported rarely. We describe a 3-year-old boy with profound biotinidase deficiency who presented with progressive spastic paraparesis and ascending weakness in the absence of the usual characteristic neurological manifestations. Supplementation with biotin resulted in resolution of paraparesis with persistent mild spasticity in the lower limbs. DNA mutation analysis revealed that he was homozygous for a novel missense mutation (C>T1339;H447Y) in the BTD gene. This case indicates that biotinidase deficiency should be included in the differential diagnosis of subacute myelopathy and emphasizes the importance of a prompt diagnosis to prevent irreversible neurological damage.
Apparent Life-Threatening Events: Neurological Correlates and the Mandatory Work-Up
Authors: Genizi Jacob , Pillar Giora , Ravid Sarit , Shahar Eli
Published: July 2008

The purpose of this study was to estimate the prevalence of neurological causes for apparent life-threatening events in infants and assess the neurological work-up mandatory to diagnose such diagnosis, hypothesizing that acute neurological disorders constitute the most common etiology for such an acute event. A retrospective chart review allocated 93 infants fulfilling the criteria of the National Institutes of Health presenting at 1 week to 8 months with apnea, color changes, gagging, unresponsiveness, and alterations of body tone. An underlying neurological etiology was detected in 18 (19%), whereby 15 had seizures and 3 had central apnea. Only one electroencephalography demonstrated epileptic discharges, and brain imaging was intact. Thus, it has been concluded that neurological impairment, mainly that of seizures inducing an apparent life-threatening event, are relatively uncommon. As such, recommendations are that history taking and repeat physical examination still remain the major diagnostic tools before resorting to extensive laboratory studies.
Pharmacologic Management of Parkinson Disease: Choice of Initial Therapy in Early Disease
Authors: Chen Jack J. , Pahwa Rajesh
Published: July 2008

The most efficacious symptomatic agent for Parkinson's disease is levodopa; however, the development of motor complications with long-term therapy is concerning. In the modern day treatment of Parkinson's disease, non-levodopa agents (eg, dopamine agonists, monoamine oxidase type B inhibitors) should be considered as appropriate initial treatments. In early Parkinson's disease, dopamine agonists provide effective symptomatic therapy, reduce the risk for motor complications, and delay the need to initiate levodopa. However, the dopamine agonists are associated with impulse control disorders and behaviors that are concerning. Monoamine oxidase type B inhibitors are also effective as monotherapy for early stage Parkinson's disease. Clinical data demonstrate that early initiation of rasagiline (in the absence of functional impairment) is associated with improved outcomes as opposed to delayed initiation. Selegiline can delay the need for levodopa, albeit its clinical effectiveness as monotherapy is equivocal. When selecting initial therapy for early Parkinson's disease, clinicians must consider both short-term and long-term benefits and risks.
Work, Employment and Society, 1997—2007
Authors: Rainbird Helen , Rose Michael
Published: July 2008

As Work, Employment & Society enters its 21st year, the co-Editors of WES for 2005—2007 take stock of the recent progress of the Journal, as shown by three main trends: regular upward growth in submissions; pluralism in terms of theory, method, and disciplinary contribution; and increasing internationalisation of the readership, author base, substantive coverage, and reputation of WES. Key features of the Journal which are believed to have contributed both to the successful establishment of the Journal in the first place and to its continuing high achievement are identified: collegiate ethos, reliance on in-house peer review, an active Editorial Board, and insistence on meaningful feed-back to authors.