Just enough structure at the edge of chaos: Agile information system development in practice

Agile information systems development is not well understood and suffers from a lack of sustainable theories, which are based on empirical research of practice. We use a framework that focuses on the ‘edge of chaos’ as the area, where agile information systems development takes place to fill in this gap. Our study identifies for a concrete project under investigation, where the beneficial balance between stability and instability lies. It discusses the circumstances, which influence this balance and the relationships of the elements, which constitute it

N-particle N-level singlet states: Some properties and applications

Three apparently unrelated problems which have no solution using classical tools are described: the "N-strangers," "secret sharing," and "liar detection" problems. A solution for each of them is proposed. Common to all three solutions is the use of quantum states of total spin zero of N spin-(N-1)/2 particles.Comment: REVTeX4, 4 pages, 1 figur

Experimental detection of entanglement via witness operators and local measurements

In this paper we address the problem of detection of entanglement using only few local measurements when some knowledge about the state is given. The idea is based on an optimized decomposition of witness operators into local operators. We discuss two possible ways of optimizing this local decomposition. We present several analytical results and estimates for optimized detection strategies for NPT states of 2x2 and NxM systems, entangled states in 3 qubit systems, and bound entangled states in 3x3 and 2x4 systems.Comment: 24 pages, 2 figures. Contribution to the proceedings of the International Conference on Quantum Information in Oviedo, Spain (July 13-18, 2002). Error in W_W1-witness Eq. (35) corrected as well as minor typos. Reference adde

In search of the origins and enduring impact of agile software development

The Agile Manifesto is a philosophical touchpoint for all agile software development (ASD) methods. We examine the manifesto and some of its associated agile methods in an effort to identify the major impacts of ASD. We have encountered some difficulty in delineating agile and non-agile software processes, which is partially the result of terminological confusion. It is clear from the volume of published research that ASD has made a significant contribution, and we have identified two lasting and important impacts. Firstly, the reduction in iteration durations and secondly, the push for reduced levels of documentation (especially in relation to software requirements). Other aspects of the Agile Manifesto may not have exerted a significant impact; for example, the use of tooling to automate processes has become central to continuous software engineering (CSE) and may not be wholly congruent with the manifesto. Furthermore, many organisations may still rely on business contracts despite calls in the manifesto for greater levels of informal customer collaboration

Historical roots of Agile methods: where did “Agile thinking” come from?

The appearance of Agile methods has been the most noticeable change to software process thinking in the last fifteen years [16], but in fact many of the “Agile ideas” have been around since 70’s or even before. Many studies and reviews have been conducted about Agile methods which ascribe their emergence as a reaction against traditional methods. In this paper, we argue that although Agile methods are new as a whole, they have strong roots in the history of software engineering. In addition to the iterative and incremental approaches that have been in use since 1957 [21], people who criticised the traditional methods suggested alternative approaches which were actually Agile ideas such as the response to change, customer involvement, and working software over documentation. The authors of this paper believe that education about the history of Agile thinking will help to develop better understanding as well as promoting the use of Agile methods. We therefore present and discuss the reasons behind the development and introduction of Agile methods, as a reaction to traditional methods, as a result of people's experience, and in particular focusing on reusing ideas from histor

Characterization of Subsurface Polycyclic Aromatic Hydrocarbons at the Deepwater Horizon Site

Here, we report the initial observations of distributions of polycyclic aromatic hydrocarbons (PAH) in subsurface waters near the Deepwater Horizon oil well site (also referred to as the Macondo, Mississippi Canyon Block 252 or MC252 well). Profiles of in situ fluorescence and beam attenuation conducted during 9-16 May 2010 were characterized by distinct peaks at depths greater than 1000 m, with highest intensities close to the wellhead and decreasing intensities with increasing distance from the wellhead. Gas chromatography/mass spectrometry (GC/MS) analyses of water samples coinciding with the deep fluorescence and beam attenuation anomalies confirmed the presence of polycyclic aromatic hydrocarbons (PAH) at concentrations reaching 189 mu g L(-1) (ppb). Subsurface exposure to PAH at levels considered to be toxic to marine organisms would have occurred in discrete depth layers between 1000 and 1400 m in the region southwest of the wellhead site and extending at least as far as 13 km. Citation: Diercks, A.-R., et al. (2010), Characterization of subsurface polycyclic aromatic hydrocarbons at the Deepwater Horizon site, Geophys. Res. Lett., 37, L20602, doi: 10.1029/2010GL045046

Evaluation of the Inheritance of Tip Moth Susceptibility Using Pine Hybrids Planted in Southeast Mississippi

Nineteen families of susceptible and resistant pine parent species and their interspecific hybrid progenies were quantitatively assessed for Nantucket pine tip moth (Rhyacionia frustrana Comstock) damage in a study in southeast Mississippi. The seeds for this study were leftover from previously performed experiments and the collection did not provide for a balanced set of families. However, it did include seven slash pine families, two shortleaf families, two loblolly families, three three-way hybrid families, one testcross hybrid family, and two F1 hybrid families of susceptible and resistant parents. The loblolly (L1 and L2) and shortleaf (Sf1 and Sf2) pine parents were susceptible, while the slash (S1 to S7) parents were resistant. The hybrids were produced from controlled pollinations that included eight additional parent trees along with the S1 slash pine parent and both of the shortleaf (Sf1 and Sf2) parents. The eight additional parent species included two F1 hybrid parents; one of which was a slash x longleaf, combining two resistant parent species and the other was a longleaf x shortleaf, combining a resistant and a susceptible parent species. The F1 hybrids in this study were the progeny of the S1 slash parent and a loblolly parent. The three-way hybrids were the progeny of the slash x longleaf F1 hybrid parent and the Sf1 and Sf2 plus one additional shortleaf parent, while the testcross hybrid was produced from the longleaf x shortleaf F1 hybrid parent and a slash pine parent. The F1 hybrid families and the three-way hybrid families were susceptible to tip moth attack like their susceptible loblolly and shortleaf parents, but tip moth damage on all of these families was significantly higher than that on the slash pine parent and testcross hybrid families. The phenotypes of the pure species and hybrid families supports a dominant mode of inheritance for susceptibility to tip moth in three different ways: (1) the phenotype of the F1 hybrids expressed the phenotype of the susceptible parents, (2) the phenotype of the three-way hybrids expressed the phenotype of the susceptible shortleaf parents when those parents were crossed with an interspecific F1 hybrid of two resistant parents, and (3) the testcross hybrid expressed a level of susceptibility that was intermediate to that of the susceptible and resistant parents when the longleaf x shortleaf F1 hybrid parent was backcrossed to a resistant slash pine parent.Papers and abstracts from the 27th Southern Forest Tree Improvement Conference held at Oklahoma State University in Stillwater, Oklahoma on June 24-27, 2003

BHLHE40 regulates the T-cell effector function required for tumor microenvironment remodeling and immune checkpoint therapy efficacy

Immune checkpoint therapy (ICT) using antibody blockade of programmed cell death protein 1 (PD-1) or cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) can provoke T cell-dependent antitumor activity that generates durable clinical responses in some patients. The epigenetic and transcriptional features that T cells require for efficacious ICT remain to be fully elucidated. Herein, we report that anti-PD-1 and anti-CTLA-4 ICT induce upregulation of the transcription factor BHLHE40 in tumor antigen-specific CD8+ and CD4+ T cells and that T cells require BHLHE40 for effective ICT in mice bearing immune-edited tumors. Single-cell RNA sequencing of intratumoral immune cells in BHLHE40-deficient mice revealed differential ICT-induced immune cell remodeling. The BHLHE40-dependent gene expression changes indicated dysregulated metabolism, NF-κB signaling, and IFNγ response within certain subpopulations of CD4+ and CD8+ T cells. Intratumoral CD4+ and CD8+ T cells from BHLHE40-deficient mice exhibited higher expression of the inhibitory receptor gene Tigit and displayed alterations in expression of genes encoding chemokines/chemokine receptors and granzyme family members. Mice lacking BHLHE40 had reduced ICT-driven IFNγ production by CD4+ and CD8+ T cells and defects in ICT-induced remodeling of macrophages from a CX3CR1+CD206+ subpopulation to an iNOS+ subpopulation that is typically observed during effective ICT. Although both anti-PD-1 and anti-CTLA-4 ICT in BHLHE40-deficient mice led to the same outcome-tumor outgrowth-several BHLHE40-dependent alterations were specific to the ICT that was used. Our results reveal a crucial role for BHLHE40 in effective ICT and suggest that BHLHE40 may be a predictive or prognostic biomarker for ICT efficacy and a potential therapeutic target

Pragmatic Software Innovation

Part 2: Creating Value through Software DevelopmentInternational audienceWe understand software innovation as concerned with introducing innovation into the development of software intensive systems, i.e. systems in which software development and/or integration are dominant considerations. Innovation is key in almost any strategy for competitiveness in existing markets, for creating new markets, or for curbing rising public expenses, and software intensive systems are core elements in most such strategies. Software innovation therefore is vital for about every sector of the economy. Changes in software technologies over the last decades have opened up for experimentation, learning, and flexibility in ongoing software projects, but how can this change be used to facilitate software innovation? How can a team systematically identify and pursue opportunities to create added value in ongoing projects? In this paper, we describe Deweyan pragmatism as the philosophical foundation for Essence – a software innovation methodology – where unknown options and needs emerge as part of the development process itself. The foundation is illustrated via a simple example

A Conceptual Model of Natural and Anthropogenic Drivers and Their Influence on the Prince William Sound, Alaska, Ecosystem

Prince William Sound (PWS) is a semi-enclosed fjord estuary on the coast of Alaska adjoining the northern Gulf of Alaska (GOA). PWS is highly productive and diverse, with primary productivity strongly coupled to nutrient dynamics driven by variability in the climate and oceanography of the GOA and North Pacific Ocean. The pelagic and nearshore primary productivity supports a complex and diverse trophic structure, including large populations of forage and large fish that support many species of marine birds and mammals. High intra-annual, inter-annual, and interdecadal variability in climatic and oceanographic processes as drives high variability in the biological populations. A risk-based conceptual ecosystem model (CEM) is presented describing the natural processes, anthropogenic drivers, and resultant stressors that affect PWS, including stressors caused by the Great Alaska Earthquake of 1964 and the Exxon Valdez oil spill of 1989. A trophodynamic model incorporating PWS valued ecosystem components is integrated into the CEM. By representing the relative strengths of driver/stressors/effects, the CEM graphically demonstrates the fundamental dynamics of the PWS ecosystem, the natural forces that control the ecological condition of the Sound, and the relative contribution of natural processes and human activities to the health of the ecosystem. The CEM illustrates the dominance of natural processes in shaping the structure and functioning of the GOA and PWS ecosystems