Showing papers by "Indiana University published in 2004"
TL;DR: It is shown that the strong coupling regime can be attained in a solid-state system, and the concept of circuit quantum electrodynamics opens many new possibilities for studying the strong interaction of light and matter.
Abstract: The interaction of matter and light is one of the fundamental processes occurring in nature, and its most elementary form is realized when a single atom interacts with a single photon. Reaching this regime has been a major focus of research in atomic physics and quantum optics1 for several decades and has generated the field of cavity quantum electrodynamics2,3. Here we perform an experiment in which a superconducting two-level system, playing the role of an artificial atom, is coupled to an on-chip cavity consisting of a superconducting transmission line resonator. We show that the strong coupling regime can be attained in a solid-state system, and we experimentally observe the coherent interaction of a superconducting two-level system with a single microwave photon. The concept of circuit quantum electrodynamics opens many new possibilities for studying the strong interaction of light and matter. This system can also be exploited for quantum information processing and quantum communication and may lead to new approaches for single photon generation and detection.
3,452 citations
TL;DR: This paper is a comprehensive exploration of all the major change detection approaches implemented as found in the literature and summarizes and reviews these techniques.
Abstract: Timely and accurate change detection of Earth's surface features is extremely important for understanding relationships and interactions between human and natural phenomena in order to promote better decision making. Remote sensing data are primary sources extensively used for change detection in recent decades. Many change detection techniques have been developed. This paper summarizes and reviews these techniques. Previous literature has shown that image differencing, principal component analysis and post-classification comparison are the most common methods used for change detection. In recent years, spectral mixture analysis, artificial neural networks and integration of geographical information system and remote sensing data have become important techniques for change detection applications. Different change detection algorithms have their own merits and no single approach is optimal and applicable to all cases. In practice, different algorithms are often compared to find the best change detection results for a specific application. Research of change detection techniques is still an active topic and new techniques are needed to effectively use the increasingly diverse and complex remotely sensed data available or projected to be soon available from satellite and airborne sensors. This paper is a comprehensive exploration of all the major change detection approaches implemented as found in the literature.
2,785 citations
TL;DR: In this paper, a realizable architecture using one-dimensional transmission line resonators was proposed to reach the strong coupling limit of cavity quantum electrodynamics in superconducting electrical circuits.
Abstract: We propose a realizable architecture using one-dimensional transmission line resonators to reach the strong-coupling limit of cavity quantum electrodynamics in superconducting electrical circuits. The vacuum Rabi frequency for the coupling of cavity photons to quantized excitations of an adjacent electrical circuit (qubit) can easily exceed the damping rates of both the cavity and qubit. This architecture is attractive both as a macroscopic analog of atomic physics experiments and for quantum computing and control, since it provides strong inhibition of spontaneous emission, potentially leading to greatly enhanced qubit lifetimes, allows high-fidelity quantum nondemolition measurements of the state of multiple qubits, and has a natural mechanism for entanglement of qubits separated by centimeter distances. In addition it would allow production of microwave photon states of fundamental importance for quantum communication.
2,633 citations
TL;DR: Treatment with pemetrexed resulted in clinically equivalent efficacy outcomes, but with significantly fewer side effects compared with docetaxel in the second-line treatment of patients with advanced NSCLC and should be considered a standard treatment option for second-liners when available.
Abstract: Purpose To compare the efficacy and toxicity of pemetrexed versus docetaxel in patients with advanced non—small-cell lung cancer (NSCLC) previously treated with chemotherapy. Patients and Methods Eligible patients had a performance status 0 to 2, previous treatment with one prior chemotherapy regimen for advanced NSCLC, and adequate organ function. Patients received pemetrexed 500 mg/m2 intravenously (IV) day 1 with vitamin B12, folic acid, and dexamethasone or docetaxel 75 mg/m2 IV day 1 with dexamethasone every 21 days. The primary end point was overall survival. Results Five hundred seventy-one patients were randomly assigned. Overall response rates were 9.1% and 8.8% (analysis of variance P = .105) for pemetrexed and docetaxel, respectively. Median progression-free survival was 2.9 months for each arm, and median survival time was 8.3 versus 7.9 months (P = not significant) for pemetrexed and docetaxel, respectively. The 1-year survival rate for each arm was 29.7%. Patients receiving docetaxel were mo...
2,366 citations
TL;DR: Barab et al. as discussed by the authors argue that learning, cognition, knowing, and context are irreducibly co-constituted and cannot be treated as isolated entities or processes.
Abstract: The emerging field of the learning sciences is one that is interdisciplinary, drawing on multiple theoretical perspectives and research paradigms so as to build understandings of the nature and conditions of learning, cognition, and development. Learning sciences researchers investigate cognition in context, at times emphasizing one more than the other but with the broad goal of developing evidence-based claims derived from both laboratory-based and naturalistic investigations that result in knowledge about how people learn. This work can involve the development of technological tools, curriculum, and especially theory that can be used to understand and support learning. A fundamental assumption of many learning scientists is that cognition is not a thing located within the individual thinker but is a process that is distributed across the knower, the environment in which knowing occurs, and the activity in which the learner participates. In other words, learning, cognition, knowing, and context are irreducibly co-constituted and cannot be treated as isolated entities or processes. If one believes that context matters in terms of learning and cognition, research paradigms that simply examine these processes as isolated variables within laboratory or other impoverished contexts of participation will necessarily lead to an incomplete understanding of their relevance in more naturalistic settings (Brown, 1992).1 Alternatively, simply observing learning and cognition as they naturally Correspondence and requests for reprints should be sent to Sasha A. Barab, School of Education,
2,233 citations
TL;DR: The findings suggest that autologous delivery of either native or transduced subcutaneous ASCs, which are regulated by hypoxia, may be a novel therapeutic option to enhance angiogenesis or achieve cardiovascular protection.
Abstract: Background— The delivery of autologous cells to increase angiogenesis is emerging as a treatment option for patients with cardiovascular disease but may be limited by the accessibility of sufficient cell numbers. The beneficial effects of delivered cells appear to be related to their pluripotency and ability to secrete growth factors. We examined nonadipocyte stromal cells from human subcutaneous fat as a novel source of therapeutic cells. Methods and Results— Adipose stromal cells (ASCs) were isolated from human subcutaneous adipose tissue and characterized by flow cytometry. ASCs secreted 1203±254 pg of vascular endothelial growth factor (VEGF) per 106 cells, 12 280±2944 pg of hepatocyte growth factor per 106 cells, and 1247±346 pg of transforming growth factor-β per 106 cells. When ASCs were cultured in hypoxic conditions, VEGF secretion increased 5-fold to 5980±1066 pg/106 cells (P=0.0016). The secretion of VEGF could also be augmented 200-fold by transfection of ASCs with a plasmid encoding VEGF (P<0...
2,174 citations
TL;DR: It is suggested that network analysis offers new fundamental insights into global and integrative aspects of brain function, including the origin of flexible and coherent cognitive states within the neural architecture.
1,983 citations
TL;DR: In this article, the applicability of vegetation fraction derived from a spectral mixture model as an alternative indicator of vegetation abundance was investigated based on examination of a Landsat Enhanced Thematic Mapper Plus (ETM+) image of Indianapolis City, IN, USA, acquired on June 22, 2002.
1,917 citations
TL;DR: Allan R. Tunkel, Barry J. Hartman, Sheldon L. Kaplan, Bruce A. Kaufman, Karen L. Roos, W. Michael Scheld, and Richard J. Scheld are the authors of this study, which aims to contribute to the understanding of central nervous system disorders and its role in disease.
Abstract: Allan R. Tunkel, Barry J. Hartman, Sheldon L. Kaplan, Bruce A. Kaufman, Karen L. Roos, W. Michael Scheld, and Richard J. Whitley Drexel University College of Medicine, Philadelphia, Pennsylvania; Weill Cornell Medical Center, New York, New York; Baylor College of Medicine, Houston, Texas; Medical College of Wisconsin, Milwaukee; Indiana University School of Medicine, Indianapolis; University of Virginia School of Medicine, Charlottesville; and University of Alabama at Birmingham
1,835 citations
TL;DR: A large fraction of the Caenorhabditis elegans interactome network is mapped, starting with a subset of metazoan-specific proteins, and more than 4000 interactions were identified from high-throughput, yeast two-hybrid screens.
Abstract: To initiate studies on how protein-protein interaction (or "interactome") networks relate to multicellular functions, we have mapped a large fraction of the Caenorhabditis elegans interactome network. Starting with a subset of metazoan-specific proteins, more than 4000 interactions were identified from high-throughput, yeast two-hybrid (HT=Y2H) screens. Independent coaffinity purification assays experimentally validated the overall quality of this Y2H data set. Together with already described Y2H interactions and interologs predicted in silico, the current version of the Worm Interactome (WI5) map contains approximately 5500 interactions. Topological and biological features of this interactome network, as well as its integration with phenome and transcriptome data sets, lead to numerous biological hypotheses.
1,733 citations
TL;DR: Open MPI provides a unique combination of novel features previously unavailable in an open-source, production-quality implementation of MPI, which provides both a stable platform for third-party research as well as enabling the run-time composition of independent software add-ons.
Abstract: A large number of MPI implementations are currently available, each of which emphasize different aspects of high-performance computing or are intended to solve a specific research problem. The result is a myriad of incompatible MPI implementations, all of which require separate installation, and the combination of which present significant logistical challenges for end users. Building upon prior research, and influenced by experience gained from the code bases of the LAM/MPI, LA-MPI, and FT-MPI projects, Open MPI is an all-new, production-quality MPI-2 implementation that is fundamentally centered around component concepts. Open MPI provides a unique combination of novel features previously unavailable in an open-source, production-quality implementation of MPI. Its component architecture provides both a stable platform for third-party research as well as enabling the run-time composition of independent software add-ons. This paper presents a high-level overview the goals, design, and implementation of Open MPI.
TL;DR: These studies describe a clonogenic method to define a hierarchy of EPCs based on their proliferative potential, and they identify a unique population of high proliferation potential-endothelial colony-forming cells (HPP-ECFCs) in human umbilical cord blood.
TL;DR: This review examines the evidence of cellular oxidants' involvement in the carcinogenesis process, and focuses on the mechanisms for production, cellular damage produced, and the role of signaling cascades by reactive oxygen species.
Abstract: ▪ Abstract Chemical carcinogenesis follows a multistep process involving both mutation and increased cell proliferation. Oxidative stress can occur through overproduction of reactive oxygen and nitrogen species through either endogenous or exogenous insults. Important to carcinogenesis, the unregulated or prolonged production of cellular oxidants has been linked to mutation (induced by oxidant-induced DNA damage), as well as modification of gene expression. In particular, signal transduction pathways, including AP-1 and NFκB, are known to be activated by reactive oxygen species, and they lead to the transcription of genes involved in cell growth regulatory pathways. This review examines the evidence of cellular oxidants' involvement in the carcinogenesis process, and focuses on the mechanisms for production, cellular damage produced, and the role of signaling cascades by reactive oxygen species.
TL;DR: The results suggest that the mechanism of translation reinitiation involving uORFs is conserved from yeast to mammals.
Abstract: During cellular stresses, phosphorylation of eukaryotic initiation factor-2 (eIF2) elicits gene expression designed to ameliorate the underlying cellular disturbance. Central to this stress response is the transcriptional regulator activating transcription factor, ATF4. Here we describe the mechanism regulating ATF4 expression involving the differential contribution of two upstream ORFs (uORFs) in the 5′ leader of the mouse ATF4 mRNA. The 5′ proximal uORF1 is a positive-acting element that facilitates ribosome scanning and reinitiation at downstream coding regions in the ATF4 mRNA. When eIF2-GTP is abundant in nonstressed cells, ribosomes scanning downstream of uORF1 reinitiate at the next coding region, uORF2, an inhibitory element that blocks ATF4 expression. During stress conditions, phosphorylation of eIF2 and the accompanying reduction in the levels of eIF2-GTP increase the time required for the scanning ribosomes to become competent to reinitiate translation. This delayed reinitiation allows for ribosomes to scan through the inhibitory uORF2 and instead reinitiate at the ATF4-coding region. Increased expression of ATF4 would contribute to the expression of genes involved in remediation of cellular stress damage. These results suggest that the mechanism of translation reinitiation involving uORFs is conserved from yeast to mammals.
TL;DR: It is clear that the environment and people from North America are very much more contaminated with PBDEs as compared to Europe and that these PBDE levels have doubled every 4-6 yr.
Abstract: Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in many types of consumer products. Perhaps as a result of their widespread use and their lipophilicity, these compounds have become ubiquitous in the environment and in people. This review summarizes PBDE concentrations measured in several environmental media and analyzes these data in terms of relative concentrations, concentration trends, and congener profiles. In human blood, milk, and tissues, total PBDE levels have increased exponentially by a factor of ∼100 during the last 30 yr; this is a doubling time of ∼5 yr. The current PBDE concentrations in people from Europe are ∼2 ng/g lipid, but the concentrations in people from the United States are much higher at ∼35 ng/g lipid. Current PBDE concentrations in marine mammals from the Canadian Arctic are very low at ∼5 ng/g lipid, but they have increased exponentially with a doubling time of ∼7 yr. Marine mammals from the rest of the world have current PBDE levels of ∼1000 ng/g lipid, and...
TL;DR: For example, this paper found that 80.3% of the world's largest MNEs are based in the triad of NAFTA, the European Union and Asia, and that the majority of their sales are concentrated in these three markets.
Abstract: Multinational enterprises (MNEs) are the key drivers of globalization, as they foster increased economic interdependence among national markets. The ultimate test to assess whether these MNEs are global themselves is their actual penetration level of markets across the globe, especially in the broad ‘triad’ markets of NAFTA, the European Union and Asia. Yet, data on the activities of the 500 largest MNEs reveal that very few are successful globally. For 320 of the 380 firms for which geographic sales data are available, an average of 80.3% of total sales are in their home region of the triad. This means that many of the world’s largest firms are not global but regionally based, in terms of breadth and depth of market coverage. Globalization, in terms of a balanced geographic distribution of sales across the triad, thus reflects a special, and rather unusual, outcome of doing international business (IB). The regional concentration of sales has important implications for various strands of mainstream IB research, as well as for the broader managerial debate on the design of optimal strategies and governance structures for MNEs. Journal of International Business Studies (2004) 35, 3–18. doi:10.1057/palgrave. jibs.8400073
TL;DR: This paper looks at the institutional configurations that affect the interactions among resources, resource users, public infrastructure providers, and public infrastructures and proposes a framework that helps identify potential vulnerabilities of SESs to disturbances.
Abstract: What makes social-ecological systems (SESs) robust? In this paper, we look at the institutional configurations that affect the interactions among resources, resource users, public infrastructure providers, and public infrastructures. We propose a framework that helps identify potential vulnerabilities of SESs to disturbances. All the links between components of this framework can fail and thereby reduce the robustness of the system. We posit that the link between resource users and public infrastructure providers is a key variable affecting the robustness of SESs that has frequently been ignored in the past. We illustrate the problems caused by a disruption in this link. We then briefly describe the design principles originally developed for robust common-pool resource institutions, because they appear to be a good starting point for the development of design principles for more general SESs and do include the link between resource users and public infrastructure providers.
TL;DR: In this paper, the authors make specific suggestions for conceptualizing and defining creativity to maximize its potential contributions to educational psychology, and make use of the fact that creativity appears to be an important component of problem-solving and other cognitive abilities, healthy social and emotional well-being.
Abstract: The construct of creativity has a great deal to offer educational psychology. Creativity appears to be an important component of problem-solving and other cognitive abilities, healthy social and emotional well-being, and scholastic and adult success. Yet the study of creativity is not nearly as robust as one would expect, due in part to the preponderance of myths and stereotypes about creativity that collectively strangle most research efforts in this area. The root cause of these stereotypes is the lack of adequate precision in the definition of creativity. The body of the article is devoted to specific suggestions for conceptualizing and defining creativity to maximize its potential contributions to educational psychology.
TL;DR: Viewed in this analysis from a statistical physics perspective, the Internet is perceived as a developing system that evolves through the addition and removal of nodes and links, allowing the authors to outline the dynamical theory that can appropriately describe the Internet's macroscopic evolution.
Abstract: Viewed in this analysis from a statistical physics perspective, the Internet is perceived as a developing system that evolves through the addition and removal of nodes and links. This perspective permits the authors to outline the dynamical theory that can appropriately describe the Internet's macroscopic evolution. The presence of such a theoretical framework will provide a revolutionary way of enhancing the reader's understanding of the Internet's varied network processes.
TL;DR: All cortical connection matrices examined in this study exhibit “small-world” attributes, characterized by the presence of abundant clustering of connections combined with short average distances between neuronal elements.
Abstract: While much information is available on the structural connectivity of the cerebral cortex, especially in the primate, the main organizational principles of the connection patterns linking brain areas, columns and individual cells have remained elusive. We attempt to characterize a wide variety of cortical connectivity data sets using a specific set of graph theory methods. We measure global aspects of cortical graphs including the abundance of small structural motifs such as cycles, the degree of local clustering of connections and the average path length. We examine large-scale cortical connection matrices obtained from neuroanatomical data bases, as well as probabilistic connection matrices at the level of small cortical neuronal populations linked by intra-areal and interareal connections. All cortical connection matrices examined in this study exhibit “small-world” attributes, characterized by the presence of abundant clustering of connections combined with short average distances between neuronal elements. We discuss the significance of these universal organizational features of cortex in light of functional brain anatomy. Supplementary materials are at www.indiana.edu/∼cortex/lab.htm.
TL;DR: The authors employ meta-analytic techniques to empirically assess the impact of the most commonly researched antecedent variables on post-acquisition performance, and find robust results indicating that acquiring firms' performance does not positively change as a function of their acquisition activity, and is negatively affected to a modest extent.
Abstract: Empirical research has not consistently identified antecedents for predicting post-acquisition performance. We employ meta-analytic techniques to empirically assess the impact of the most commonly researched antecedent variables on post-acquisition performance. We find robust results indicating that, on average and across the most commonly studied variables, acquiring firms' performance does not positively change as a function of their acquisition activity, and is negatively affected to a modest extent. More importantly, our results indicate that unidentified variables may explain significant variance in post-acquisition performance, suggesting the need for additional theory development and changes to M&A research methods. Copyright © 2003 John Wiley & Sons, Ltd.
TL;DR: The ability of the PHQ-9 to detect depression outcome and changes over time is demonstrated in three groups of patients whose depression status either improved, remained unchanged, or deteriorated over time.
TL;DR: This article examined the relationship between participating in learning communities and student engagement in a range of educationally purposeful activities of first-year and senior students from 365 4-year institutions and found that participating in a learning community is positively linked to engagement as well as student self-reported outcomes and overall satisfaction with college.
Abstract: This study examines the relationships between participating in learning communities and student engagement in a range of educationally purposeful activities of first-year and senior students from 365 4-year institutions. The findings indicate that participating in a learning community is positively linked to engagement as well as student self-reported outcomes and overall satisfaction with college.
Journal Article•
Tufts University1, Wake Forest University2, Oregon Health & Science University3, Indiana University4, Albany College of Pharmacy and Health Sciences5, Rush University Medical Center6, Vanderbilt University7, East Carolina University8, University of Illinois at Chicago9, Beaumont Hospital10, Johns Hopkins University11, Cleveland Clinic12, University of Wisconsin-Madison13, University of Texas at Austin14, University of Pittsburgh15, Virginia Commonwealth University16, Texas Tech University Health Sciences Center17, National Institutes of Health18, University of Virginia19
TL;DR: The purpose of the Executive Summary is to provide a "stand-alone" summary of the background, scope, methods, and key recommendations, as well as the complete text of the guideline statements.
TL;DR: A critical review of research related to informal reasoning regarding socioscientific issues can be found in this article, where the authors discuss the relationship between nature of science conceptualizations and socio-scientific decision making.
Abstract: Socioscientific issues encompass social dilemmas with conceptual or technological links to science. The process of resolving these issues is best characterized by informal reasoning which describes the generation and evaluation of positions in response to complex situations. This article presents a critical review of research related to informal reasoning regarding socioscientific issues. The findings reviewed address (a) socioscientific argumentation; (b) relationships between nature of science conceptualizations and socioscientific decision making; (c) the evaluation of information pertaining to socioscientific issues, including student ideas about what counts as evidence; and (d) the influence of an individual's conceptual understanding on his or her informal reasoning. This synthesis of the current state of socioscientific issue research provides a comprehensive framework from which future research can be motivated and decisions about the design and implementation of socioscientific curricula can be made. The implications for future research and classroom applications are discussed. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 513–536, 2004
TL;DR: In this article, the role of the gravitational sector in the Lorentz and CPT-violating standard-model extension (SME) is studied, and the leading-order terms in the SME action involving operators of mass dimension three and four are constructed.
Abstract: The role of the gravitational sector in the Lorentz- and CPT-violating standard-model extension (SME) is studied. A framework is developed for addressing this topic in the context of Riemann-Cartan spacetimes, which include as limiting cases the usual Riemann and Minkowski geometries. The methodology is first illustrated in the context of the QED extension in a Riemann-Cartan background. The full SME in this background is then considered, and the leading-order terms in the SME action involving operators of mass dimension three and four are constructed. The incorporation of arbitrary Lorentz and CPT violation into general relativity and other theories of gravity based on Riemann-Cartan geometries is discussed. The dominant terms in the effective low-energy action for the gravitational sector are provided, thereby completing the formulation of the leading-order terms in the SME with gravity. Explicit Lorentz symmetry breaking is found to be incompatible with generic Riemann-Cartan geometries, but spontaneous Lorentz breaking evades this difficulty.
TL;DR: A variety of potentially therapeutic growth factors were detected and released from the platelets in significant levels in platelet-rich plasma preparations and may be capable of expediting wound healing in a variety of as yet undetermined specific wound applications.
Abstract: Growth factors released from activated platelets initiate and modulate wound healing in both soft and hard tissues. A recent strategy to promote the wound-healing cascade is to prepare an autologous platelet concentrate suspended in plasma, also known as platelet-rich plasma, that contains growth factors and administer it to wound sites. The purpose of this study was to quantitate platelet number and growth factors released from a prepared platelet concentrate. Whole blood was drawn from 10 healthy patients undergoing cosmetic surgery and concentrated into platelet-rich plasma. Platelet counts on whole blood and platelet-rich plasma were determined using a Cell-Dyn 3200. Platelet-derived growth factor-BB, transforming growth factor-[beta]1, vascular endothelial growth factor, endothelial growth factor, and insulin-like growth factor-1 were measured in the platelet-rich plasma using the enzyme-linked immunosorbent assay method. In addition, platelet activation during the concentration procedure was analyzed by measuring P selectin values in blood serum. An 8-fold increase in platelet concentration was found in the platelet-rich plasma compared with that of whole blood (baseline whole blood, 197 ± 42 × 10 3
TL;DR: All three questionnaires performed well in depression screening, but significant differences in criterion validity existed; these results may be helpful in the selection of questionnaires and cut-off points.
TL;DR: The authors studied the influence of implicit and explicit knowledge transfer in the transfer of knowledge from the foreign parent to the international joint venture (IJV) managers and found that implicit learning is accumulative, assists in explaining explicit knowledge, and is enhanced by social embeddedness.
Abstract: Drawing on organizational learning and economic sociology, we address how relational embeddedness between the foreign parent and international joint venture (IJV) managers influences the type of knowledge (i.e., tacit and explicit) transferred to the IJV, and how the importance of relational embeddedness varies between young and mature IJVs. We also examine the influence of tacit and explicit knowledge on IJV performance. Our results show the importance that tie strength, trust, and shared values and systems play in the transfer of tacit knowledge, especially for mature IJVs. Our findings are consistent with Uzzi's tenets: tacit learning is accumulative, assists in explaining explicit knowledge, and is enhanced by social embeddedness. We also find that the influence of transferred tacit knowledge on IJV performance stems principally from its indirect effect on the learning of explicit knowledge.
05 Jan 2004
TL;DR: A content analysis of 203 randomly-selected Weblogs considers the likely antecedents of the blog genre, situate it with respect to the dominant forms of digital communication on the Internet today, and advance predictions about its long-term impacts.
Abstract: Weblogs (blogs) - frequently modified Web pages in which dated entries are listed in reverse chronological sequence - are the latest genre of Internet communication to attain widespread popularity, yet their characteristics have not been systematically described. This paper presents the results of a content analysis of 203 randomly-selected Weblogs, comparing the empirically observable features of the corpus with popular claims about the nature of Weblogs, and finding them to differ in a number of respects. Notably, blog authors, journalists and scholars alike exaggerate the extent to which blogs are interlinked, interactive, and oriented towards external events, and underestimate the importance of blogs as individualistic, intimate forms of self-expression. Based on the profile generated by the empirical analysis, we consider the likely antecedents of the blog genre, situate it with respect to the dominant forms of digital communication on the Internet today, and advance predictions about its long-term impacts.