Rethinking the Physical Symbol Systems Hypothesis

It is now more than a half-century since the Physical Symbol Systems Hypothesis (PSSH) was first articulated as an empirical hypothesis. More recent evidence from work with neural networks and cognitive architectures has weakened it, but it has not yet been replaced in any satisfactory manner. Based on a rethinking of the nature of computational symbols -- as atoms or placeholders -- and thus also of the systems in which they participate, a hybrid approach is introduced that responds to these challenges while also helping to bridge the gap between symbolic and neural approaches, resulting in two new hypotheses, one that is to replace the PSSH and other focused more directly on cognitive architectures.Comment: Final version published at the the 16th Annual AGI Conference, 202

Thoughts on Architecture

The term architecture has evolved considerably from its original Greek roots and its application to buildings and computers to its more recent manifestation for minds. This article considers lessons from this history, in terms of a set of relevant distinctions introduced at each of these stages and a definition of architecture that spans all three, and a reconsideration of three key issues from cognitive architectures for architectures in general and cognitive architectures more particularly

Defining and Explorting the Intelligence Space

Intelligence is a difficult concept to define, despite many attempts at doing so. Rather than trying to settle on a single definition, this article introduces a broad perspective on what intelligence is, by laying out a cascade of definitions that induces both a nested hierarchy of three levels of intelligence and a wider-ranging space that is built around them and approximations to them. Within this intelligence space, regions are identified that correspond to both natural -- most particularly, human -- intelligence and artificial intelligence (AI), along with the crossover notion of humanlike intelligence. These definitions are then exploited in early explorations of four more advanced, and likely more controversial, topics: the singularity, generative AI, ethics, and intellectual property.Comment: May ultimately appear as a journal article and/or a book chapte

Predicting the outcomes of treatment to eradicate the latent reservoir for HIV-1

Massive research efforts are now underway to develop a cure for HIV infection, allowing patients to discontinue lifelong combination antiretroviral therapy (ART). New latency-reversing agents (LRAs) may be able to purge the persistent reservoir of latent virus in resting memory CD4+ T cells, but the degree of reservoir reduction needed for cure remains unknown. Here we use a stochastic model of infection dynamics to estimate the efficacy of LRA needed to prevent viral rebound after ART interruption. We incorporate clinical data to estimate population-level parameter distributions and outcomes. Our findings suggest that approximately 2,000-fold reductions are required to permit a majority of patients to interrupt ART for one year without rebound and that rebound may occur suddenly after multiple years. Greater than 10,000-fold reductions may be required to prevent rebound altogether. Our results predict large variation in rebound times following LRA therapy, which will complicate clinical management. This model provides benchmarks for moving LRAs from the lab to the clinic and can aid in the design and interpretation of clinical trials. These results also apply to other interventions to reduce the latent reservoir and can explain the observed return of viremia after months of apparent cure in recent bone marrow transplant recipients and an immediately-treated neonate.Comment: 8 pages main text (4 figures). In PNAS Early Edition http://www.pnas.org/content/early/2014/08/05/1406663111. Ancillary files: SI, 24 pages SI (7 figures). File .htm opens a browser-based application to calculate rebound times (see SI). Or, the .cdf file can be run with Mathematica. The most up-to-date version of the code is available at http://www.danielrosenbloom.com/reboundtimes

Mobility patterns of the elderly tourist in Algarve

The present work is part of the Project for Scientific Research and Techno-logical Development "Accessibility for All in Tourism" focuses on modal in-terfaces designed according to the concepts of "Universal Design" and "Age Sensitive Design". In this project 851 surveys were carried out for elderly tourists, who arrived in Algarve (Portugal) through the international Airport of Faro, in the summer of 2018, with a view to understanding their prefer-ences and needs in terms of mobility. It presents the characterization of the senior tourist in Algarve, according to: gender, age, academic qualification, situation in the relation to the profession, nationality, disability and/or disa-bilities that affects mobility and the need to use technical aids to move. It analyses and compares, from the point of view of sustainable mobility, the mobility of the elderly tourist, by gender and age group, in the country where they reside and in the Algarve region. This information is useful for local au-thorities and for transport operators in order to make the mobility of elderly tourists, in Algarve, more sustainable from a social, economic and environ-mental standpoint.The Research Project ACCES4ALL - Accessibility for All in Tourisminfo:eu-repo/semantics/publishedVersio

Clinical Diagnosis of Placenta Accreta and Clinicopathological Outcomes

Objective To investigate the association between the intraoperative diagnosis of placenta accreta at the time of cesarean hysterectomy and pathological diagnosis. Study Design This is a retrospective cohort study of all patients undergoing cesarean hysterectomy for suspected placenta accreta from 2000 to 2016 at Barnes-Jewish Hospital. The primary outcome was the presence of invasive placentation on the pathology report. We estimated predictive characteristics of clinical diagnosis of placenta accreta using pathological diagnosis as the correct diagnosis. Results There were 50 cesarean hysterectomies performed for suspected abnormal placentation from 2000 to 2016. Of these, 34 (68%) had a diagnosis of accreta preoperatively and 16 (32%) were diagnosed intraoperatively at the time of cesarean delivery. Two patients had no pathological evidence of invasion, corresponding to a false-positive rate of 4% (95% confidence interval [CI]: 0.5%, 13.8%) and a positive predictive value of 96% (95% CI: 86.3%, 99.5%). There were no differences in complications among patients diagnosed intraoperatively compared with those diagnosed preoperatively. Conclusion Most patients undergoing cesarean hysterectomy for placenta accreta do have this diagnosis confirmed on pathology. However, since the diagnosis of placenta accreta was made intraoperatively in nearly a third of cesarean hysterectomies, intraoperative vigilance is required as the need for cesarean hysterectomy may not be anticipated preoperatively

The Unruly World of Tax: A Proposal for an International Tax Cooperation Forum

International cooperation in tax policy is deeply fractured. Inconsistencies, loopholes, and ineffective mechanisms—which could be avoided if real collaboration among countries existed—have created significant inefficiency losses for decades. This Article focuses on the institutional infrastructure underlying international cooperation in tax issues and argues that the current forums in which such cooperation is encouraged do not provide an adequate platform in which countries with similar interests can effectively make a collaborative effort. To facilitate cooperation, this Article proposes to create a new institution currently missing from the international tax policy-setting arena: an informal forum for coordination among countries that share similar interests in tax policy, inspired by the model of “Like Minded Groups” in international organizations. This forum will enable countries that share similar interests to cooperate and reach understandings about necessary policy adaptations. We identify two major projects that this forum could promote—efforts to curtail tax evasion and efforts to harmonize various aspects of tax policy. We argue that this model might have significant advantages in promoting cooperation, reducing the “competitiveness” threat, advocating coordinated policies, and overcoming external and domestic pressures. In light of the current challenges in the field of tax policy, and the difficulties in forming international cooperation within the current institutional framework, the proposed model is worth serious discussion and consideration

Growth hormone receptor deficiency (Laron syndrome) in black African siblings

Non-Caucasians with growth honnone receptor (GHR) deficiency/Lamn syndrome among the approximately 180 recognised cases are rare, and include a Japanese and 3 African Americans. Black African siblings, a brother and a sister seen initially at 11 years 9 months and 5 years 6 months of age respectively were -7,4 and -8,0 on the standard deviation score for height. They had characteristic features and biochemical findings including prominent forehead; depressed nasal bridge; central adiposity; high-pitched voices; micropenis; high GH levels and low levels of insulin-like growth factor (IGF)-I, IGF-II, insulin-like growth factor-binding protein 3 (IGFBP-3), and GH-binding protein (the solubilised extracellular domain of the GH cell surface receptor). Molecular genetic studies revealed a dinucleotide deletion in both siblings on exon 7 of the GHR gene, a mutation not found in any other G.HRdeficient patient studied, including the North Americans of African origin. Since African Americans have a substantial admixture of Caucasian genes, n is of interest to document the presence of this ccndnion in siblings from Afric