4,195 research outputs found
IT Project Retrospectives: Learning from the Past through a Program of Action Research
Project management has emerged as a strong discipline practiced by highly trained, certified professionals as organizations have come to realize they cannot stay in business if they cannot manage their projects effectively. However, most companies are still unable or unwilling to perform the most basic of continuous improvement activities – identifying and learning from past mistakes and successes. To help address this shortcoming, this paper provides a framework for conducting project retrospectives that has evolved through the analysis of 130 IT projects over the past ten years. By integrating the findings of several previous studies, the paper provides guidance on mapping project momentum, evaluating project success, identifying and avoiding classic mistakes through best practices, performing root cause analysis, and delivering actionable recommendations
Chitobiose utilization in Borrelia burgdorferi is dually regulated by RpoD and RpoS
<p>Abstract</p> <p>Background</p> <p><it>Borrelia burgdorferi </it>has limited biosynthetic capabilities and must scavenge N-acetylglucosamine (GlcNAc), an essential component of the microbial cell wall, from the surrounding environment. Spirochetes cultured in the absence of free GlcNAc exhibit biphasic growth; however, addition of chitobiose (a dimer of GlcNAc) substitutes for free GlcNAc resulting in a single exponential phase. We evaluated the effect of RpoS and RpoN, the only alternative sigma factors in <it>B. burgdorferi</it>, on biphasic growth and chitobiose utilization in the absence of free GlcNAc. In addition, we investigated the source of GlcNAc in the second exponential phase.</p> <p>Results</p> <p>By comparing the growth of wild-type cells to insertional mutants for <it>rpoS </it>and <it>rpoN </it>we determined that RpoS, but not RpoN, partially regulates both biphasic growth and chitobiose utilization. The <it>rpoS </it>mutant, cultured in the absence of free GlcNAc, exhibited a significant delay in the ability to initiate a second exponential phase compared to the wild type and <it>rpoS </it>complemented mutant. Expression analysis of <it>chbC</it>, which encodes the membrane-spanning protein of the chitobiose phosphotransferase system, suggests the delay is due to the inability of the <it>rpoS </it>mutant to up regulate <it>chbC</it>. Furthermore, supplementing GlcNAc starved cultures with high concentrations (75 or 150 μM) of chitobiose resulted in biphasic growth of the <it>rpoS </it>mutant compared to a single exponential phase for the wild type and <it>rpoS </it>complemented mutant. In contrast, growth of the <it>rpoN </it>mutant under all conditions was similar to the wild type. 5' Rapid amplification of cDNA ends (5' RACE) revealed the transcriptional start site for <it>chbC </it>to be 42 bp upstream of the translational start site. Analysis of the <it>chbC </it>promoter region revealed homology to previously described RpoD and RpoS <it>B. burgdorferi </it>promoters. We also determined that yeastolate, a component of the growth medium (BSK-II), is not essential for second exponential phase growth.</p> <p>Conclusion</p> <p>Together these results suggest that RpoD and RpoS, but not RpoN, regulate biphasic growth and chitobiose utilization in <it>B. burgdorferi </it>by regulating the expression of the chitobiose transporter (<it>chbC</it>). The data also demonstrate that the second exponential phase observed in wild-type cells in the absence of free GlcNAc is not due to free chitobiose or GlcNAc oligomers present in the medium.</p
Synthesizing Qualitative Evidence: A Roadmap for Information Systems Research
Qualitative synthesis research is an approach that consolidates the output of different qualitative studies to create new subject knowledge. Such work can help reveal more powerful explanations than that seen in a single study, thereby generating increased levels of understanding of a given phenomenon and greater research finding generalizability. Based on a review of the literature and a survey of qualitative researchers, we found that the information systems (IS) domain lacks a clear understanding of qualitative synthesis methods and, as a result, has largely failed to take advantage of this powerful, high-potential methodological opportunity. To address this shortcoming, this paper is the first to provide a rigorous overview of the full suite of 35 qualitative synthesis methods, as well as guidelines that include a three-tiered selection framework. By using the guidelines and framework in tandem, IS researchers are able to select the qualitative synthesis method most appropriate for a given research study, particularly when the research objective involves knowledge integration/aggregation, interpretation/theory development, and/or informing IS practice
The chitobiose transporter, chbC, is required for chitin utilization in Borrelia burgdorferi
<p>Abstract</p> <p>Background</p> <p>The bacterium <it>Borrelia burgdorferi</it>, the causative agent of Lyme disease, is a limited-genome organism that must obtain many of its biochemical building blocks, including N-acetylglucosamine (GlcNAc), from its tick or vertebrate host. GlcNAc can be imported into the cell as a monomer or dimer (chitobiose), and the annotation for several <it>B. burgdorferi </it>genes suggests that this organism may be able to degrade and utilize chitin, a polymer of GlcNAc. We investigated the ability of <it>B. burgdorferi </it>to utilize chitin in the absence of free GlcNAc, and we attempted to identify genes involved in the process. We also examined the role of RpoS, one of two alternative sigma factors present in <it>B. burgdorferi</it>, in the regulation of chitin utilization.</p> <p>Results</p> <p>Using fluorescent chitinase substrates, we demonstrated an inherent chitinase activity in rabbit serum, a component of the <it>B. burgdorferi </it>growth medium (BSK-II). After inactivating this activity by boiling, we showed that wild-type cells can utilize chitotriose, chitohexose or coarse chitin flakes in the presence of boiled serum and in the absence of free GlcNAc. Further, we replaced the serum component of BSK-II with a lipid extract and still observed growth on chitin substrates without free GlcNAc. In an attempt to knockout <it>B. burgdorferi </it>chitinase activity, we generated mutations in two genes (<it>bb0002 </it>and <it>bb0620</it>) predicted to encode enzymes that could potentially cleave the β-(1,4)-glycosidic linkages found in chitin. While these mutations had no effect on the ability to utilize chitin, a mutation in the gene encoding the chitobiose transporter (<it>bbb04</it>, <it>chbC</it>) did block utilization of chitin substrates by <it>B. burgdorferi</it>. Finally, we provide evidence that chitin utilization in an <it>rpoS </it>mutant is delayed compared to wild-type cells, indicating that RpoS may be involved in the regulation of chitin degradation by this organism.</p> <p>Conclusions</p> <p>The data collected in this study demonstrate that <it>B. burgdorferi </it>can utilize chitin as a source of GlcNAc in the absence of free GlcNAc, and suggest that chitin is cleaved into dimers before being imported across the cytoplasmic membrane via the chitobiose transporter. In addition, our data suggest that the enzyme(s) involved in chitin degradation are at least partially regulated by the alternative sigma factor RpoS.</p
Reviewing the Past for a Better Future: Reevaluating the IT Project Retrospective
This paper provides a commentary on previous research to inform our understanding of IT project retrospectives. The literature surrounding project retrospective outcomes, measurement and processes are discussed, and critical factors necessary for project retrospective success are considered. Consequently, semi-structured interviews are undertaken with experienced project managers to determine levels of agreement between research and practitioner disciplines. Outcome findings include multiple project retrospective definitions being used, differing project retrospective outcomes being desired, thirteen project retrospective processes being advocated, and no project retrospective measurements given to confirm whether these outcomes have been successfully achieved. Subsequently, project retrospective processes are presented such that each process has the capability to deliver on any outcome irrespective of its nature. Further research is suggested necessary to pursue a more rigorous and relevant conceptual understanding of the IT project retrospective construct
The Delphi Method Research Strategy in Studies of Information Systems
In this paper, we discuss the nature and use of the Delphi methodology in information systems research. More specifically, we explore how and why it may be used. We discuss criteria for evaluating Delphi research and define characteristics useful for categorizing the studies. We review Delphi application use in IS research over the last 23 years, summarize lessons learned from prior studies, offer suggestions for improvement, and present guidelines for employing this distinctly useful qualitative method in future information systems research studies
Planning for Failure: An Exploratory Study of a Proactive IS Project Recovery Team
Despite extensive research on project management over the past several decades, numerous cases of IS project failure continue to surface, undermining organizational performance in almost every industry. The ongoing nature of this issue obliges the IS discipline to consider alternative approaches to avoiding failure before it’s too late. In this paper, a proactive approach to project recovery is presented – one that involves a full-time recovery team responsible for turning around IS projects in distress. Using the findings gleaned from an in-depth case study inquiry, this paper analyzes the composition and structure of a dedicated project recovery team in a global organization. The investigation revealed (1) a process model of IS project recovery that comprises seven stages of evolution, (2) requisite attributes and skills of project recovery specialists, and (3) the differences between project recovery and project management. The implications arising from this novel study for both research and practice are discussed
Using the theory of planned behavior to predict gambling behavior
Gambling is an important public health concern. To better understand gambling behavior, we conducted a classroom-based survey that assessed the role of the theory of planned behavior (TPB; i.e., intentions, subjective norms, perceived behavioral control, and attitudes) in past year gambling and gambling frequency among college students. Results from this research support the utility of the TPB to explain gambling behavior in this population. Specifically, in TPB models to predict gambling behavior, friend and family subjective norms and perceived behavioral control predicted past year gambling and friend and family subjective norms, attitudes and perceived behavioral control predicted gambling frequency. Intention to gamble mediated these relationships. These findings suggest that college responsible gambling efforts should consider targeting misperceptions of approval regarding gambling behavior (i.e., subjective norms), personal approval of gambling behavior (i.e., attitudes), and perceived behavioral control to better manage gambling behavior in various situations
A Pre-Exercise Dose of Melatonin Can Alter Substrate Use During Exercise
International Journal of Exercise Science 10(7): 1029-1037, 2017. Notwithstanding the lack of exercise research, several reviews have championed the use of melatonin to combat metabolic syndrome. Therefore, this study compared substrate utilization during a 30-minute (min) graded exercise protocol following the ingestion of either 6 mg melatonin (M) or a placebo (P). Participants (12 women, 12 men) performed stages 1-5 of the Naughton graded exercise protocol (6 min per stage). The protocol was repeated 4 times (2x M, 2x P) at the same time of day with one week separating each session. Expired gases were monitored, VO2 and respiratory exchange ratio (RER) output was provided every 30s. Total, carbohydrate (CHO), and fat energy expenditures were obtained from the RER values using the formulae of Lusk. The VO2 at which CHO accounted for 50% of the total caloric expenditure was calculated by a VO2: RER regression line. Additionally, the energy derived was calculated by multiplying VO2 and the respective energy expenditures. Then, the total, CHO, and fat energies consumed during the 30 min of exercise were determined by calculating the area under the kJ/min: time curve using the trapezoid rule. The final data for the two similar trials were averaged and a paired-T test was used for statistical comparison. The average VO2 for 50% CHO usage was significantly lower following M (0.84 ± 0.54 l·min-1) than after P (1.21 ± 0.52 l·min-1). Also, average CHO kJ for M (627 ± 284) was significantly (p \u3c 0.004) greater than P (504 ± 228), and accounted for a significantly greater contribution of total kJ consumed (M = 68% ±15 vs. P = 61% ± 18). Ingestion of melatonin 30 min prior to an aerobic exercise bout elevates CHO use during exercise
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