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This paper analyzed the ultimate grout-to-soil bond strength based on a database of 40 full-scale static load tests conducted on micropiles in glacial deposits in the province of Ontario, Canada. The Decourt extrapolation method was used to extrapolate the field load–settlement curves to identify the ultimate limit state. The elastic length method was modified by considering the shear stress influence to more accurately predict the failure loads of micropiles. A set of the ultimate bond strengths were correlated with the field standard penetration test blow count for different types of micropiles in different soil conditions. The results were compared with existing design values recommended by the Federal Highway Administration manual. The findings will help to improve the design of micropiles in similar soil conditions and the development of a reliability-based design method for soil-bonded micropiles.

The 24-week extension of AIDS Clinical Trials Group Protocol 359, a study of human immunodeficiency virus (HIV)‐infected, indinavir-experienced patients, was designed to study the durability of “salvage” treatment regimens. Patients received saquinavir in combination with either ritonavir or nelfinavir and, in addition, delavirdine, adefovir, or both. Patients who demonstrated a virologic response at weeks 12‐16 were eligible to continue therapy in the extension through week 48. Of the 105 eligible subjects who were enrolled in the extension, 86 (82%) completed 48 weeks, and 49 (57%) of those 86 had HIV RNA levels 500 copies/ mL at week 48. For these 86 subjects who completed 48 weeks, the median change in CD4 cell count from baseline was +72 cells/mm 3 . Greater body weight, higher CD4 cell count, and greater degree of phenotypic susceptibility to indinavir and saquinavir at baseline were significantly associated with durable virologic suppression. These results show that some patients who experience treatment failure can demonstrate durable virologic and immunologic responses with salvage antiretroviral regimens. Current treatment guidelines recommend starting therapy for human immunodeficiency virus (HIV) infection with 2 nucleoside analogue reverse-transcriptase inhibitors in combination with 1 or 2 protease inhibitors or a nonnucleoside analogue reversetranscriptase inhibitor [1, 2]. However, 20%‐63% of patients from clinical cohorts experience virologic treatment failure while receiving combination antiretroviral therapy [3‐7]. Recent prospective studies have attempted to identify strategies for treatment of the treatment-experienced patient [8‐13], but these studies have focused primarily on 8‐24-week virologic responses to treatment. The durability of virologic and immunologic re

To identify the underlying mechanisms that limit the mitotic potential of normal somatic cells, we have undertaken a high resolution differential proteomic analysis aimed at identifying proteins that were differentially expressed upon replicative senescence. Since replicative senescence in heterogeneous primary fibroblast cultures is asynchronous, we analysed a group of conditionally immortalized rat embryo fibroblast cell lines that have previously been shown to undergo synchronous senescence upon inactivation of SV40 tsA58 T antigen. This identified 43 spots that were differentially expressed in these cell lines. Comparison of the identity of these features with those identified in a complimentary independent differential proteomic analysis of replicative senescence, directly in primary rat embryo fibroblasts upon serial passaging, identified nine features that were in common between the two studies even though they had been conducted entirely separately. None of these proteins have previously been recognized to be involved with replicative senescence. Thus, they represent novel starting points for elucidating the underlying mechanism that regulates the finite mitotic life span of somatic cells and how it can be overcome in cancer cells.

Normal somatic cells undergo a finite number of divisions and then cease dividing whereas cancer cells are able to proliferate indefinitely. To identify the underlying mechanisms that limit the mitotic potential, a two-dimensional differential proteome analysis of replicative senescence in serially passaged rat embryo fibroblasts was undertaken. Triplicate independent two-dimensional gels containing over 1200 spots each were run, curated, and analyzed. This revealed 49 spots whose expression was altered more than 2-fold. Of these, 42 spots yielded positive protein identification by mass spectrometry comprising a variety of cytoskeletal, heat shock, and metabolic proteins, as well as proteins involved in trafficking, differentiation, and protein synthesis, turnover, and modification. These included gelsolin, a candidate tumor suppressor for breast cancer, and alpha-glucosidase II, a member of the family of glucosidases that includes klotho; a defect in klotho expression in mice results in a syndrome that resembles human aging. Changes in expression of TUC-1, -2, -4, and -4 beta, members of the TUC family critical for neuronal differentiation, were also identified. Some of the identified changes were also shown to occur in two other models of senescence, premature senescence of REF52 cells and replicative senescence of mouse embryo fibroblasts. The majority of these candidate proteins were unrecognized previously in replicative senescence. They are now implicated in a new role.

Not all disciplines have the benefit of a Capability Maturity Model (CMM) that they can use to focus and guide their improvement activities. Honeywell Space Systems Operations, in cooperation with SECAT LLC, developed a “generic Capability Maturity Model” which included only project and organizational management topic areas, and was designed to be applicable to all disciplines. The model, called the IPDP CMM, was developed in early 1998. The first assessment was performed in the Fall of 1998 for 8 individual disciplines. A rating profile was developed for each discipline, and strengths and weaknesses both common across the organization and unique to each discipline were identified. A few lessons learned for improving the model and the assessment method were found during the assessment which are discussed in this paper, but generally all of the teams found the results applicable and particularly helpful in focusing their improvement efforts. The goal of this paper is to present what was done, the rationale for the decisions, the lessons learned and the benefits of developing and using a generic CMM.

Abstract The analysis of historical satellite data, both radar and optical, areuseful for understanding the nature of ice conditions in Arctic regions andunderstanding the risk they pose for exploration and development. Archivesatellite data are available at no cost and can be analyzed to assess theseverity and variability of iceberg concentrations and their behavior. National ice centres have been providing charts of sea ice conditions, whichcan be analyzed to understand probabilities of encountering ice of variousconcentrations and the lengths of the open water season. The outputs ofthese analyses are useful for understanding the risk of operating in Arcticregions and for developing an ice management plan. Introduction Satellite radar and optical imagery are essential tools for understandingsea ice and iceberg conditions in frontier Arctic and sub-Arctic regions. Satellite synthetic aperture radar (SAR) imagery can be collected day or night, are relatively independent of environmental conditions, can be collectedthrough fog and cloud cover and provide information over remote areas at noadditional cost. There is a substantial archive of low resolution imageryavailable and there is a growing number of sensors available for newacquisitions. Optical imagery, when available, are excellent forproviding detailed information on ice features such as sea ice ridges andiceberg sizes. Low resolution optical data are collected continuously, medium resolution data is available close to shore and high resolution imagescan be acquired from a large number of sensors. Historic satellite data are used to develop an understanding of the severityand variability of ice conditions in an area. This information serves asan input for the design of structures and selection of vessels that can beutilized in an area as well for development of an ice management plan anddefining the operational window. New image acquisitions are an important part of the detection component ofan operational ice management plan. Surveillance in certain marginal icezones, such as the Grand Banks, do not rely on satellite imagery since they areclose to shore and reconnaissance can be carried out almost exclusively usingplatform radar and vessel and aerial surveillance. However, the costs ofthis approach grow in remote areas and satellite SAR data have been used inaddition to platform radar to support operations in new Arctic explorationregions.

The Pipeline Ice Risk Assessment & Mitigation JIP (PIRAM) developed a set of engineering models and design procedures for implementation into industry best practices for risk mitigation and protection of pipeline infrastructure from ice keel loading. The models established the pipeline mechanical behaviour in response to ice keel load events, and assessed engineering concepts for protection and risk mitigation strategies. Improved methodologies for contact frequency and ice keel loads determination formed part of the integrated model. This paper presents an overview of this multiyear program and examples of the application of the models in pipeline burial depth assessment in pressure ridge ice gouged seabeds.

Oil and gas exploration activities in iceberg populated waters require careful planning to ensure operations are conducted with the utmost attention to safety and environmental protection while minimizing iceberg related downtime. This paper describes a methodology for estimating downtime and providing a tool to plan ice management fleet requirements for operations.

Although still somewhat obscure and seldom utilized, hot melt grouts have for decades proven useful in stopping high magnitude inflows (Schonian & Naudts, 2003). In 2002, injection of hot bitumen in combination with low mobility and high mobility cement-based grouts succeeded in eliminating a 2205 l /sec (35,000 GPM) inflow into the Lonestar Quarry in Cape Girardeau, Missouri. By 2002, quarrying at the site had been active for over 100 years and the quarry floor at the locus of the inflow was more than 100 metres lower than prevailing grade. The source of the inflow was the nearby Mississippi River. Two principal inflow pathways were identified, each of them large conduits measuring as great as 6 metres wide x 9 metres high and centered 76 metres and 93 metres below prevailing grade, respectively. Grouting holes were drilled on a line parallel to the quarry face, transverse to the strike of the inflow path and set back approximately 80 metres from the quarry face. Prior to hot bitumen grouting, several weeks and thousands of tons of cement were consumed attempting, unsuccessfully, to reduce the inflow. Once the program was eventually shifted to hot bitumen grouting, drilling and cement grouting operations were redirected to focus on flushing clean any sediment-filled, inactive features, and filling these with a competent grout in advance of the eventual hot bitumen grouting intervention. Concurrently, an array of new injection wells was drilled consisting of four hot bitumen injection wells, two low mobility cement-based grout injection wells and five high mobility cement-based grout injection wells, all for simultaneous use in a final assault on the inflow. This final assault, with hot bitumen injection playing the key role, succeeded in completely stopping the inflow within just seven hours of the start of grouting. © 2012 Geo-Foundations Contractors Inc. (www.geo-foundations.com)

The magnitude of ice loads imposed onto a structure located in land fast ice, such as an ice island, is usually controlled by the failure mechanism of the ice at the interface with the structure – crushing of the ice sheet or passive edge failure of the ice island. These ice loads are resisted by a grounded ice island through sliding resistance along the seafloor and internal shear within the island. Methods of assessing ice loads imposed on ice islands are addressed, focusing on alternative mechanisms which may result in lower failure loads than using traditional analysis. A comparison is made between the requirements of various codes of practice and guidance documents available to the industry, including the recently updated CSA S471-04. Potential methods of reducing ice loads using monitoring of ice conditions and active operational management are also reviewed and discussed, as well as potential areas for future research and development.

Oligosaccharidesingl co roteinsmay generally be attached to eptides in two ways, gy 8-glycosidic linkage to asparagine or g 0-glycosidic linka e to serine or threonine. The structures of &can chain attachecfthrough each linkage are different and they can have different structural and functional roles. Although in the past more attention has been aid to N-linked glycans there is currently growing interest in &inked glycans. Detailed study of the structure of the lycans r uires their release from the peptide. A number of di B " i , erent met ods, both chemical and enzymatic exist. Enzymatic methods such as ycosidase F may give incomplete or selective re

For offshore pipelines located in ice environments, the mitigation of ice gouge hazards presents a significant technical challenge. A traditional strategy is to establish minimum burial depth requirements that meet technical and economic criteria. A probabilistic based approach to optimize burial depth requirements based on equivalent stress and compressive strain limit state criteria is presented. The basic methodology is to define ice gouge hazards on a statistical basis, to develop numerical algorithms that model ice gouge mechanisms and pipeline/soil interaction events, to define failure criteria, limit states and target reliability levels and to conduct a probabilistic assessment of pipeline burial depth requirements. Application of the probabilistic design methodology for a generic pipeline design scenario subject to ice gouge hazards is presented. Implications on pipeline design and future applied research initiatives are discussed.Copyright © 2004 by ASME