Axial Load Behavior of a Driven Cast-In-Situ Pile in Sand

Driven cast-in-situ (DCIS) piles are a popular choice amongst piling contractors due to the ability to readily adjust pile lengths to suit the depth of penetration required. Despite their widespread use, there is a dearth of published data on the axial load behavior of temporary-cased DCIS piles, particularly in cohesionless soils. This paper reports the results of a static compression load test on a 340 mm nominal diameter, 5.75 m long DCIS pile in a dense sand deposit in Shotton, Wales. The test pile was instrumented with vibrating-wire strain gauges at various levels to determine the shaft and base resistance during loading. Analysis of the test results showed that pile behavior was predominantly end-bearing, with the base resistance accounting for approximately 81 % of the total capacity at a displacement of 10 % of the pile diameter. The pile exhibited a stiff stress-displacement response during the initial stages of loading due to the level of pre-stress applied to the soil beneath the base during driving of the steel installation tube. The displacement required to mobilize the shaft resistance was similar to that reported for preformed displacement piles, with a peak local shaft friction of 105 kPa occurring near the base of the pile which diminished with increasing distance from the tip. Finally, the load test results were compared with two popular CPT-based design methods (LCPC and Imperial College methods) for displacement piles in sand. Despite having specific empirical correlations for DCIS piles, the LCPC method significantly under-predicted the capacity of the test pile

Appraising vibro-settlement prediction methods using the finite element method

ABSTRACT. Numerous approaches exist for the prediction of the settlement improvement offered by the vibro-replacement technique in weak or marginal soil deposits. The majority of the settlement prediction methods are based on the unit cell assumption, with a small number based on plane strain or homogenization techniques. In this paper, a comprehensive review and assessment of the more popular settlement prediction methods is carried out with a view to establishing which method(s) are in best agreement with finite element predictions from a series of PLAXIS 2D axisymmetric analyses on an end-bearing column. The Hardening Soil Model in PLAXIS 2D has been used to model the behaviour of both the granular column material and the treated soft clay soil. This study has shown that purely elastic settlement prediction methods overestimate the settlement improvement for large modular ratios while the methods based on elastic-plastic theory are in better agreement with finite element predictions at higher modular ratios (in some cases owing to the assumption of a significant bulging mechanism which is more prevalent in soft soils and in other cases due to the variability of soil stiffness with stress level which is considered in the FE calculations but not in the analytical solutions). In addition, a parameter sensitivity study has been carried out to establish the influence of a range of different design parameters on predictions obtained using a selection of elastic-plastic methods

Interventions for preventing oral mucositis for patients with cancer receiving treatment

Background: Treatment of cancer with chemotherapy is becoming increasingly more effective but is associated with short and long-term side effects. Oral side effects remain a major source of illness despite the use of a variety of agents to prevent them. Objectives: To evaluate the effectiveness of oral (and topical) prophylactic agents for oral mucositis and oral candidiasis in patients with cancer (excluding head and neck cancer), compared with placebo or no treatment. Search Strategy: Computerised MEDLINE, EMBASE, CINAHL, CANCERLIT, the Cochrane Controlled Trials Register and the Cochrane Oral Health Group Specialist Register search up to July 1999. Reference lists from relevant articles were scanned and the authors of eligible studies were contacted to identify trials and obtain additional information. Selection Criteria: Studies were selected if they met the following criteria: design - random or quasi-random allocation of participants; participants - anyone with cancer receiving chemotherapy (excluding head and neck cancer); interventions - prophylactic agents prescribed to reduce oral conditions arising from cancer or its treatment; outcomes - mucositis and oral candidiasis. Data Collection and Analysis: Information regarding methods, participants, interventions and outcome measures and results were independently extracted, in duplicate, by two reviewers (JC &amp; HW). Specialist advice was sought to categorise interventions. Authors were contacted for details of randomisation and withdrawals and a quality assessment was carried out using the Jadad criteria (Jadad 1998). The Cochrane Oral Health Group statistical guidelines were followed and relative risk values calculated using random effects models where significant heterogeneity was detected (P &lt; 0.1). Main Results: Thirty-eight reports of trials were initially included. Two were duplicate reports and nine were excluded as there was no useable information. Of the 27 useable studies 14 had data for mucositis comprising 945 randomised patients and 15 included data for oral candidiasis with 1164 randomised patients. Of the eight prophylactic agents used for mucositis only one, ice chips, was effective (Relative risk 0.57, 95% CI 0.43 to 0.77, chi-square for heterogeneity = 0.26 (df = 1), p = 0.61). The NNT to prevent one extra case of mucositis over the baseline incidence using ice chips was 4 (95%CI: 3 to 7). The NNT for when the baseline incidence of mucositis in the population ranges from 50% to 80% are 5 to 4 respectively. There is evidence that antifungal agents which are partially or fully absorbed from the gastrointestinal tract prevent oral candidiasis and that the partially absorbed agents may be more effective than the fully absorbed agents. The RR for partially absorbed agents was 0.13 (95% CI 0.06 to 0.27, chi-square for heterogeneity = 5.3 (df = 3), P = 0. 15). The NNT to prevent one extra case of oral candidiasis over the baseline incidence using partially absorbed drugs was 3 (95% CI: 3 to 5). The NNT for when the baseline incidence of oral candidiasis in the population ranges from 30% to 70% are 4 to 2 respectively. The general reporting of RCT's was poor however the median Jadad score was acceptable and improved further when the authors provided additional information. The sensitivity analysis confirmed the findings for oral candidiasis. Reviewer's Conclusions: There is some evidence that ice chips prevent mucositis. None of the other prophylactic agents included in this review prevented mucositis. There is evidence that prophylactic use of antifungal agents which are absorbed or partially absorbed from the gastrointestinal tract reduce the clinical signs of oral candidiasis, and the partially absorbed drugs may be more effective. Future trials in this area should address the link between oral and general health including outcomes relevant to the patient. Collaboration between medical and dental teams is indicated.</p

April 15, 2004

The Breeze is the student newspaper of James Madison University in Harrisonburg, Virginia

MicroRNA profiling of the bovine alveolar macrophage response to Mycobacterium bovis infection suggests pathogen survival is enhanced by microRNA regulation of endocytosis and lysosome trafficking

peer-reviewedMycobacterium bovis, the causative agent of bovine tuberculosis, a major problem for global agriculture, spreads via an airborne route and is taken up by alveolar macrophages (AM) in the lung. Here, we describe the first next-generation sequencing (RNA-seq) approach to temporally profile miRNA expression in primary bovine AMs post-infection with M. bovis. One, six, and forty miRNAs were identified as significantly differentially expressed at 2, 24 and 48 h post-infection, respectively. The differential expression of three miRNAs (bta-miR-142-5p, bta-miR-146a, and bta-miR-423-3p) was confirmed by RT-qPCR. Pathway analysis of the predicted mRNA targets of differentially expressed miRNAs suggests that these miRNAs preferentially target several pathways that are functionally relevant for mycobacterial pathogenesis, including endocytosis and lysosome trafficking, IL-1 signalling and the TGF-β pathway. Over-expression studies using a bovine macrophage cell-line (Bomac) reveal the targeting of two key genes in the innate immune response to M. bovis, IL-1 receptor-associated kinase 1 (IRAK1) and TGF-β receptor 2 (TGFBR2), by miR-146. Taken together, our study suggests that miRNAs play a key role in tuning the complex interplay between M. bovis survival strategies and the host immune response

Principles of Good Practice for Decision Analytic Modeling in Health-Care Evaluation: Report of the ISPOR Task Force on Good Research Practices - Modeling Studies

Principles of Good Practice for Decision Analytic Modeling in Health-Care Evaluation: Report of the ISPOR Task Force on Good Research Practices - Modeling Studies Abstract. Objectives: Mathematical modeling is used widely in economic evaluations of pharmaceuticals and other healthcare technologies. Users of models in government and the private sector need to be able to evaluate the quality of models according to scientific criteria of good practice. This report describes the consensus of a task force convened to provide modelers with guidelines for conducting and reporting modeling studies. Methods: The task force was appointed with the advice and consent of the Board of Directors of ISPOR. Members were experienced developers or users of models, worked in academia and industry, and came from several countries in North America and Europe. The task force met on three occasions, conducted frequent correspondence and exchanges of drafts by electronic mail, and solicited comments on three drafts from a core group of external reviewers and more broadly from the membership of ISPOR. Results: Criteria for assessing the quality of models fell into three areas: model structure, data used as inputs to models, and model validation. Several major themes cut across these areas. Models and their results should be represented as aids to decision making, not as statements of scientific fact; therefore, it is inappropriate to demand that models be validated prospectively before use. However, model assumptions regarding causal structure and parameter estimates should be continually assessed against data, and models should be revised accordingly. Structural assumptions and parameter estimates should be reported clearly and explicitly, and opportunities for users to appreciate the conditional relationship between inputs and outputs should be provided through sensitivity analyses. Conclusions: Model-based evaluations are a valuable resource for health-care decision makers. It is the responsibility of model developers to conduct modeling studies according to the best practicable standards of quality and to communicate results with adequate disclosure of assumptions and with the caveat that conclusions are conditional upon the assumptions and data on which the model is built

US Cosmic Visions: New Ideas in Dark Matter 2017: Community Report

This white paper summarizes the workshop "U.S. Cosmic Visions: New Ideas in Dark Matter" held at University of Maryland on March 23-25, 2017.Comment: 102 pages + reference

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

The PHENIX Experiment at RHIC

The physics emphases of the PHENIX collaboration and the design and current status of the PHENIX detector are discussed. The plan of the collaboration for making the most effective use of the available luminosity in the first years of RHIC operation is also presented.Comment: 5 pages, 1 figure. Further details of the PHENIX physics program available at http://www.rhic.bnl.gov/phenix