In this full review paper, the recent emerging trends in Computing Structures, Software Science, and System Applications have been reviewed and explored to address the recent topics and contributions in the era of the Software and Computing fields. This includes a set of rigorously reviewed world-class manuscripts addressing and detailing state-of-the-art, framework, implemented approaches and techniques research projects in the areas of Software Technology & Automation, Networking, Systems, Computing Sciences and Software Engineering, Big Data and E-learning. Based on this systematic (...) review, we have put some recommendations and suggestions for researchers, practitioners and scholars to improve their research quality in this area. (shrink)

In recent decades, there has been a proliferation among the scientific community of works that focus on Alan Turing’s contributions to the design and development of the modern computer. However, there are significant discrepancies among these studies, to such a point that some of them cast serious doubts on Alan Turing’s work with respect to today’s computer, and there are others that staunchly defend his leading role, as well as other studies that set out more well-balanced opinions. Faced with this (...) situation, the aim of this paper is to analyse the evidence existing today in order to be able to draw a conclusion about whether or not Turing anticipated the trivialisation of the modern computer memory and, likewise, if his universal a-machine is the precursor of the general-purpose computer so omnipresent today. As a result of our research, the authors conclude that Turing did indeed play a leading role in the appearance of the modern computer, although he was not the only one or the first in the field of Computing Science, albeit he was the most influential, both in scope and in depth. (shrink)

Turing was an exceptional mathematician with a peculiar and fascinating personality and yet he remains largely unknown. In fact, he might be considered the father of the von Neumann architecture computer and the pioneer of Artificial Intelligence. And all thanks to his machines; both those that Church called “Turing machines” and the a-, c-, o-, unorganized- and p-machines, which gave rise to evolutionary computations and genetic programming as well as connectionism and learning. This paper looks at all of these and (...) at why he is such an often overlooked and misunderstood figure. (shrink)

Recommender Systems (RecSys) have been around since the early days of the Internet, helping users navigate the vast ocean of information and the increasingly available options that have been available for us ever since. The range of tasks for which one could use a RecSys is expanding as the technical capabilities grow, with the disruption of Machine Learning representing a tipping point in this domain, as in many others. However, the increase of the technical capabilities of AI-powered RecSys did not (...) come with a thorough consideration of their ethical implications and, despite being a well-established technical domain, the potential impacts of RecSys on their users are still under-assessed. This paper aims at filling this gap in regards to one of the main impacts of RecSys: personal autonomy. We first describe how technology can affect human values and a suitable methodology to identify these effects and mitigate potential harms: Value Sensitive Design (VSD). We use VSD to carry out a conceptual investigation of personal autonomy in the context of a generic RecSys and draw on a nuanced account of procedural autonomy to focus on two components: competence and authenticity. We provide the results of our inquiry as a value hierarchy and apply it to the design of a speculative RecSys as an example. (shrink)

In this paper, I develop a criticism to a method for metaontology, namely, the idea that a discourse’s or theory’s ontological commitments can be read off its sentences’ truth- conditions. Firstly, I will put forward this idea’s basis and, secondly, I will present the way Quine subscribed to it. However, I distinguish between two readings of Quine’s famous ontological criterion, and I center the focus on the one currently dubbed “ontological minimalism”, a kind of modern Ockhamism applied to the mentioned (...) metaontological view. I show that this view has a certain application via Quinean thesis of reference inscrutability but that it is not possible to press that application any further and, in particular, not for the ambitious metaontological task some authors try to employ. The conclusion may sound promising: having shown the impossibility of a semantic ontological criterion, intentionalist or subjectivist ones should be explored. (shrink)

The state of computing science and, particularly, software engineering and knowledge engineering is generally considered immature. The best starting point for achieving a mature engineering discipline is a solid scientific theory, and the primary reason behind the immaturity in these fields is precisely that computing science still has no such agreed upon underlying theory. As theories in other fields of science do, this paper formally establishes the fundamental elements and postulates making up a first attempt at a theory in this (...) field, considering the features and peculiarities of computing science. The fundamental elements of this approach are informons and holons, and it is a general and comprehensive theory of software engineering and knowledge engineering that related disciplines (e.g., information systems) can particularise and/or extend to take benefit from it (Lakatos’ concepts of core theory and protective belt theories). (shrink)

Dynamic Assessment (DA) has been shown to have more predictive value than conventional tests for academic performance. However, in relation to reading difficulties, further research is needed to determine the predictive validity of DA for specific aspects of the different processes involved in reading and the differential validity of DA for different subgroups of students with an academic disadvantage. This paper analyzes the implementation of a DA device that evaluates processes involved in reading (EDPL) among 60 students with reading comprehension (...) difficulties between 9 and 16 years of age, of whom 20 have intellectual disabilities, 24 have reading-related learning disabilities, and 16 have socio-cultural disadvantages. We specifically analyze the predictive validity of the EDPL device over attitude towards reading, and the use of dialogue/participation strategies in reading activities in the classroom during the implementation stage. We also analyze if the EDPL device provides additional information to that obtained with a conventionally applied personal-social adjustment scale (APSL). Results showed that dynamic scores, obtained from the implementation of the EDPL device, significantly predict the studied variables. Moreover, dynamic scores showed a significant incremental validity in relation to predictions based on an APSL scale. In relation to differential validity, the results indicated the superior predictive validity for DA for students with intellectual disabilities and reading disabilities than for students with socio-cultural disadvantages. Furthermore, the role of metacognition and its relation to the processes of personal-social adjustment in explaining the results is discussed. (shrink)

Similarity profiled association mining from time stamped transaction databases is an important topic of research relatively less addressed in the field of temporal data mining. Mining temporal patterns from these time series databases requires choosing and applying similarity measure for similarity computations and subsequently pruning temporal patterns. This research proposes a novel z-space based interest measure named as Krishna Sudarsana for time-stamped transaction databases by extending interest measure Srihass proposed in previous research. Krishna Sudarsana is designed by using the product (...) based fuzzy Gaussian membership function and performs similarity computations in z-space to determine the similarity degree between any two temporal patterns. The interest measure is designed by considering z-values between z = 0 and z = 3.09. Applying the Krishna Sudarsana requires moving the threshold value given by user to a different transformation space which is a defined as a function of standard deviation. In addition to proposing interest measure, new expressions for standard deviation and equivalent z-space threshold are derived for similarity computations. For experimental evaluation, we considered Naïve, Sequential and Spamine algorithms that applies Euclidean distance function and compared performance of these three approaches to Z-Spamine algorithm that uses Krishna Sudarsana by choosing various test cases. Experiment results proved the performance of the proposed approach is better to Sequential approach that uses snapshot database scan strategy and Spamine approach that uses lattice based database scan strategy. (shrink)

In the centenary year of Turing’s birth, a lot of good things are sure to be written about him. But it is hard to find something new to write about Turing. This is the biggest merit of this article: it shows how von Neumann’s architecture of the modern computer is a serendipitous consequence of the universal Turing machine, built to solve a logical problem.

The purpose of this paper is to identify the factors that affect the intention to use Big Data Applications in companies. Research into Big Data usage intention and adoption is scarce and much less from the perspective of the use of these techniques in companies. That is why this research focuses on analyzing the adoption of Big Data Applications by companies. Further to a review of the literature, it is proposed to use a UTAUT model as a starting model with (...) the update and incorporation of other variables such as resistance to use and perceived risk, and then to perform a neural network to predict this adoption. With respect to this non-parametric technique, we found that the multilayer perceptron model for the use of Big Data Applications in companies obtains higher AUC values, and a better confusion matrix. This paper is a pioneering study using this hybrid methodology on the intention to use Big Data Applications. The result of this research has important implications for the theory and practice of adopting Big Data Applications. (shrink)

In this chapter we use methods of corpus linguistics to investigate the ways in which mathematicians describe their work as explanatory in their research papers. We analyse use of the words explain/explanation (and various related words and expressions) in a large corpus of texts containing research papers in mathematics and in physical sciences, comparing this with their use in corpora of general, day-to-day English. We find that although mathematicians do use this family of words, such use is considerably less prevalent (...) in mathematics papers than in physics papers or in general English. Furthermore, we find that the proportion with which mathematicians use expressions related to ‘explaining why’ and ‘explaining how’ is significantly different to the equivalent proportion in physics and in general English. We discuss possible accounts for these differences. (shrink)

Thomas Bonk has dedicated a book to analyzing the thesis of underdetermination of scientific theories, with a chapter exclusively devoted to the analysis of the relation between this idea and the indeterminacy of meaning. Both theses caused a revolution in the philosophic world in the sixties, generating a cascade of articles and doctoral theses. Agitation seems to have cooled down, but the point is still debated and it may be experiencing a renewed resurgence.

In this article, we report a study in which 109 research-active mathematicians were asked to judge the validity of a purported proof in undergraduate calculus. Significant results from our study were as follows: (a) there was substantial disagreement among mathematicians regarding whether the argument was a valid proof, (b) applied mathematicians were more likely than pure mathematicians to judge the argument valid, (c) participants who judged the argument invalid were more confident in their judgments than those who judged it valid, (...) and (d) participants who judged the argument valid usually did not change their judgment when presented with a reason raised by other mathematicians for why the proof should be judged invalid. These findings suggest that, contrary to some claims in the literature, there is not a single standard of validity among contemporary mathematicians. (shrink)

Despite abundant evidence associating CD38 overexpression and CD4 T cell depletion in HIV infection, no causal relation has been investigated. To address this issue, a series of mechanisms are proposed, supported by evidence from different fields, by which CD38 overexpression can facilitate CD4 T cell depletion in HIV infection. According to this model, increased catalytic activity of CD38 may reduce CD4 T cells’ cytoplasmic nicotin‐amide adenine dinucleotide (NAD), leading to a chronic Warburg effect. This will reduce mitochondrial function. Simultaneously, CD38's (...) catalytic products ADPR and cADPR may be transported to the cytoplasm, where they can activate calcium channels and increase cytoplasmic Ca2+ concentrations, further altering mitochondrial integrity. These mechanisms will decrease the viability and regenerative capacity of CD4 T cells. These hypotheses can be tested experimentally, and might reveal novel therapeutic targets. (shrink)

Psychological flexibility is a key concept of acceptation and commitment therapy. This factor has been linked with psychological wellbeing and associated factors, such as quality of life, in cancer patients. These and other positive results of acceptation and commitment therapy in cancer patients found in previous research could be enhanced by using mhealth tools. A three-arm randomized superiority clinical trial, with a pre-post-follow-up repeated measures intergroup design with a 1:1:1 allocation ratio is proposed. A hundred and twenty cancer patients will (...) be randomly assigned to one of the following interventions: face-to-face ACT + mobile application, face-to-face ACT, and Waitlist control group. The primary expected outcome is to observe significant improvements in psychological flexibility acceptance and action questionnaire- II in the face-to-face ACT + app group, after comparing baseline and post-treatment scores, and the scores will remain stable in the two assessment points, 3 and 6 months after the intervention. Secondary expected outcomes are significant increasing scores in quality of life and post-traumatic-growth, and significant decreasing scores in anxiety and depression, insomnia and fatigue at the same assessment points. Also, it is expected that the scores of this group will be higher than the scores of the face-to-face ACT group and the waitlist control group. This study aims to assess the efficacy of a combined intervention for psychological flexibility and associated symptoms in cancer patients. The results of this protocol may help to consider the use of acceptation and commitment therapy and mhealth applications in cancer settings as a valid therapeutic choice.Clinical Trial Registration[www.ClinicalTrials.gov], identifier [NCT05126823]. (shrink)

Gottfried Wilhelm Leibniz is the self-proclaimed inventor of the binary system and is considered as such by most historians of mathematics and/or mathematicians. Really though, we owe the groundwork of today’s computing not to Leibniz but to the Englishman Thomas Harriot and the Spaniard Juan Caramuel de Lobkowitz, whom Leibniz plagiarized. This plagiarism has been identified on the basis of several facts: Caramuel’s work on the binary system is earlier than Leibniz’s, Leibniz was acquainted—both directly and indirectly—with Caramuel’s work (...) and Leibniz had a natural tendency to plagiarize scientific works. (shrink)

Background: The brief generic Multicultural Quality of Life Index is a culturally informed self-report 10-item questionnaire used to measure health-related quality of life. QoL is an important outcome measure in guiding healthcare and is held as a substantial parameter to evaluate the effectiveness of healthcare. Attention Deficit Hyperactivity Disorder in children might negatively influence the parents’ QoL. Having a validated questionnaire to measure QoL for this population will therefore be a vital first step in guiding healthcare for parents of children (...) with ADHD. We aimed to examine the reliability and validity of the Norwegian version of the MQLI in a sample of parents of children with ADHD.Methods: In a cross-sectional study, 128 parents of children with ADHD were recruited from four outpatient clinics within the Child and Adolescents Mental Health Services in Norway. They completed the MQLI along with an alternative well-being scale, the Five-item World Health Organization Well-being Index, and a form including demographic variables. Reliability and validity of the MQLI were examined. We conducted a factor analysis and calculated internal consistency and the correlation between the MQLI and the WHO-5.Results: Factor analysis of the parents reported MQLI yielded a one-factor solution. For the MQLI, Cronbach’s alpha was 0.73. The correlation between the two measures of MQLI and WHO-5 was high, reflecting convergent validity since the association between the two measures was strong.Conclusion: Results from this study support the reliability and validity of the Norwegian version of the MQLI for assessment of quality of life in parents of children with ADHD with good psychometric properties. Study findings support the use of the questionnaire in CAMHS. (shrink)

Die Suche nach historischen Quellen für die Leibniz’sche Philosophie scheint zunächst unerschöpflich. Durch alle in diesem Band versammelten Arbeiten wird der Einfluss der Philosophie des Aristoteles auf das Leibniz’sche Denken näher umrissen. Ein wesentliches Ziel ist es hierbei, einen Beitrag zur Analyse dieser philosophischen Beziehung zu leisten und zu zeigen, dass auch Aristoteles’ Philosophie nach Ansicht unserer Autoren entscheidend zum Verständnis des Leibniz’schen Denkens beiträgt. Die Texte befassen sich mit wesentlichen Themen der Leibniz’schen Logik und Metaphysik, z. B. mit den (...) Grundbegriffen „Monade“ (und deren „Körperhaftigkeit“), „Entelechie“, „Nous“, mit dem Problem der Individuation (Individuum, Atomismus, Einheit), mit den substanziellen Formen, mit der Wissenschaft im Allgemeinen und der Technik, mit der Transformation der Logik, mit den Prinzipien (nämlich denjenigen des zureichenden Grundes, der Individuation und der Notwendigkeit), mit Zukunft und Kontingenz sowie Vergänglichkeit, mit der Theorie der syllogistischen Folgerung, usw. Diese Themen werden stets in der Gegenüberstellung von Leibniz und Aristoteles behandelt – sie zeigen daher, wie Leibniz aristotelische Thesen übernahm, veränderte oder kritisierte. The search for the historical sources of Leibniz’s philosphy initially seems to be unending. All the essays in this volume outline more clearly the influence of Aristotle’s philosophy on Leibniz’s thought. In this context a fundamental aim is to contribute to the analysis of this philosophical relationship and to demonstrate that Aristotle’s philosophy, in the opinion of our authors, plays a decisive role in the understanding of Leibniz’s thought. The texts address fundamental themes of Leibniz’s logic and metaphysics, e.g. the basic concepts of ‘monads’ (and their ‘corporality’), ‘entelechy’ and ‘nous; the problem of individuation (individual, atomism, unity); substantial forms; knowledge in general, and technology; the transformation of logic; principles (namely those of sufficient grounds, of individuation and of necesssity); future and contingency and transientness; the theory of syllogistic deduction, etc. These themes are regularly considered in the comparison between Leibniz and Aristotle – they demonstrate how Leibniz took over, treated or criticised Aristotelian theses. (shrink)

This article highlights two possible unnoticed acrostics in Ovid's Metamorphoses concerning the predictions of Calchas and Helenus.

Interview with Juan. A. Negrete, annual prize 2014 to the promotion of the philosophy and the culture in Málaga. The award is extended to the network of blogs: Cavernisofía, Cavernética and Cavernisofíasegundaplanta.

RESUMENLa tesis es, más bien, que la discusión del empirismo, la solución de ese reto empirista que separa el pensar del ser, forma parte de la altura histórica de la filosofía en el momento presente, es una exigencia suya. Si la filosofía comenzó buscando la unidad del ser, ha proseguido resquebrajándola; en particular distinguiendo el ser creado del increado, y luego distinguiendo el ser natural del personal, las cosas de las personas. Estas distinciones afectan de una manera muy particular a (...) las relaciones entre el ser y el pensar, y a su eventual unidad; éste es, por eso, el tema del empirismo, y de nuestro tiempo.PALABRAS CLAVESEMPIRISMO, SER, PENSARABSTRACTThe argument is that the discussion of empiricism is a requirement of philosophy at the present time, solving that challenge that separates thinking of being. If philosophy began seeking the unity of being, has continued dividing this unity; in particular distinguishing the uncreated and created being, and then distinguishing the natural and the personal being. These distinctions affect a particular the relationship between being and thinking, and his eventual drive way; it is, therefore, the issue of empiricism, and our time.KEY WORDSEMPIRICISM, BEING, THINK. (shrink)

For a theory T, we study relationships among IΔ n +1 (T), LΔ n+1 (T) and B * Δ n+1 (T). These theories are obtained restricting the schemes of induction, minimization and (a version of) collection to Δ n+1 (T) formulas. We obtain conditions on T (T is an extension of B * Δ n+1 (T) or Δ n+1 (T) is closed (in T) under bounded quantification) under which IΔ n+1 (T) and LΔ n+1 (T) are equivalent. These conditions depend (...) on Th Πn +2 (T), the Π n+2 –consequences of T. The first condition is connected with descriptions of Th Πn +2 (T) as IΣ n plus a class of nondecreasing total Π n –functions, and the second one is related with the equivalence between Δ n+1 (T)–formulas and bounded formulas (of a language extending the language of Arithmetic). This last property is closely tied to a general version of a well known theorem of R. Parikh. Using what we call Π n –envelopes we give uniform descriptions of the previous classes of nondecreasing total Π n –functions. Π n –envelopes are a generalization of envelopes (see [10]) and are closely related to indicators (see [12]). Finally, we study the hierarchy of theories IΔ n+1 (IΣ m ), m≥n, and prove a hierarchy theorem. (shrink)

Juan A. Nicolás, Department of Philosophy II, Universidad de Granada, Granada, Spain © 2010 Juan A. Nicolás Sociedad Española Leibniz has started the project ‘Leibniz en español’Leibniz in Spanish...

O presente artigo trata da influência exercida pela filosofia kantiana na actualidade a partir da chamada crise da Modernidade ilustrada. Os autores começam por analisar o posicionamento original kantiano, incidindo especialmente na sua concepção do criticismo e do transcendentalismo. Esta análise é feita a partir da perspectiva da aberta pela Kritik der Urteilskraft enquanto marco do sistema da razão, capaz de incorporar a finitude da mesma. Seguidamente são analisadas a recepção e a transformação do pensamento kantiano a partir de duas (...) correntes filosóflcas actuais: o Racionalismo Crítico de Karl Popper e Hans Albert, e a Pragmática Transcendental da linguagem de Karl-Otto Apel. Em ambos os casos se compara o sen modo próprio de incorporar as noções de crítica e transcendentalidade com a concepção original de Kant. /// The article addresses the influence of Kantian philosophy in contemporary thought from the view point of the crisis of illustrated Modernity. The authors start by analyzing the original Kantian position, whereby particular attention is given to his conception of criticism and transcendentalism. This analysis is worked out from the perspective of the Kritik der Urteilskraft as a frame for the system of reason, able to incorporate the finitude of reason itself This is followed by a detailed analysis of the reception and the transformation of illustrated thinking performed by two contemporary philosophical schools: Critical Rationalism (Karl Popper and Hans Albert), and Transcendental Pragmatics of language (Karl-Otto Apel). The authors of the article compare in each case the adoption of the notions of critique and transcendentality with the original use that Kant himself makes of them. (shrink)

English summary: G.W. Leibniz's philosophy represents a fundamental chapter in the constitution of what we mean by modernity. Leibniz can be considered a source of inspiration for both the moment of the emergence of modernity as well as for the moment of the crisis of Enlightenment. Despite his influence on various authors, Leibniz does not let himself be identified with the core of Enlightenment thinking that was prevalent in the Western world in recent centuries. We are therefore faced with a (...) thinking that in its development depends neither on the enlightened modernity, nor on the principal alternative, hermeneutics. Thus, the span of Leibniz's thought ranges from the time before the Enlightenment through to post-hermeneutics. This volume presents a selection of articles from the "IV Congreso Internacional Leibniz: G. W. Leibniz entre la genesis y la crisis de la Modernidad" which was selected by the "Sociedad Espanola Leibniz" held in Granada. German, English, & French text. German description: Die Philosophie G. W. Leibniz stellt ein grundlegendes Kapitel fuer die Konstituierung dessen dar, was wir unter Modernitat verstehen. Leibniz kann als eine Inspirationsquelle sowohl im Moment der Entstehung der Modernitat als auch im Moment der Krise der Aufklarung verstanden werden. Trotz seines Einflusses auf verschiedene Autoren lasst sich Leibniz nicht mit dem Kern des aufklarerischen Denkens identifizieren, das in der westlichen Welt in den letzten Jahrhunderten vorherrschend war. Wir stehen also vor einem Denken, das in seinem Werdegang weder von der aufgeklarten Modernitat noch von deren hauptsachlicher Alternative, der Hermeneutik, abhangt. Somit spannt sich der Bogen des Denkens Leibniz von der Zeit vor der Aufklarung bis hin zur Post-Hermeneutik. Dieser Sammelband prasentiert eine Auswahl der Beitrage auf dem IV Congreso Internacional Leibniz: G. W. Leibniz entre la genesis y la crisis de la Modernidad, der von der Sociedad espanola Leibniz in Granada abgehalten wurde. Die Studien umfassen vier thematische Bereiche: Leibniz und die Entstehung der Modernitat, die Prinzipien der Philosophie und der Naturwissenschaften, die Sprachphilosophie und die Erkenntnistheorie, Ontologie und Theodizee. (shrink)

English summary: G.W. Leibniz's philosophy represents a fundamental chapter in the constitution of what we mean by modernity. Leibniz can be considered a source of inspiration for both the moment of the emergence of modernity as well as for the moment of the crisis of Enlightenment. Despite his influence on various authors, Leibniz does not let himself be identified with the core of Enlightenment thinking that was prevalent in the Western world in recent centuries. We are therefore faced with a (...) thinking that in its development depends neither on the enlightened modernity, nor on the principal alternative, hermeneutics. Thus, the span of Leibniz's thought ranges from the time before the Enlightenment through to post-hermeneutics. This volume presents a selection of articles from the "IV Congreso Internacional Leibniz: G. W. Leibniz entre la genesis y la crisis de la Modernidad" which was selected by the "Sociedad Espanola Leibniz" held in Granada. German, English, & French text. German description: Die Philosophie G. W. Leibniz stellt ein grundlegendes Kapitel fur die Konstituierung dessen dar, was wir unter Modernitat verstehen. Leibniz kann als eine Inspirationsquelle sowohl im Moment der Entstehung der Modernitat als auch im Moment der Krise der Aufklarung verstanden werden. Trotz seines Einflusses auf verschiedene Autoren lasst sich Leibniz nicht mit dem Kern des aufklarerischen Denkens identifizieren, das in der westlichen Welt in den letzten Jahrhunderten vorherrschend war. Wir stehen also vor einem Denken, das in seinem Werdegang weder von der aufgeklarten Modernitat noch von deren hauptsachlicher Alternative, der Hermeneutik, abhangt. Somit spannt sich der Bogen des Denkens Leibniz von der Zeit vor der Aufklarung bis hin zur Post-Hermeneutik. Dieser Sammelband prasentiert eine Auswahl der Beitrage auf dem IV Congreso Internacional Leibniz: G. W. Leibniz entre la genesis y la crisis de la Modernidad, der von der Sociedad espanola Leibniz in Granada abgehalten wurde. Die Studien umfassen vier thematische Bereiche: Leibniz und die Entstehung der Modernitat, die Prinzipien der Philosophie und der Naturwissenschaften, die Sprachphilosophie und die Erkenntnistheorie, Ontologie und Theodizee. (shrink)

On pose la question de la justification du principe de la raison suffisante dans la philosophic leibnizienne. On part de la portée universelle que Leibniz attribue au principe dans beaucoup de textes. Mais en même temps Leibniz montre aussi certains limites de ce principe qui empechent, au moins apparemment, son universalité. II s'agit des champs dont il n'est pas possible de rendre raison. Pour eviter cette paradoxe on applique le principe sur lui m& me. A partir de Tautoapplication du principe (...) on propose une fondamentarion du meme dans la ligne de la philosophic transcendantale. (shrink)

Chondrogenesis is a key process in skeletogenesis since endochondral ossification requires the formation of a cartilaginous template. Knowledge of molecular mechanisms regulating chondrogenesis is extremely valuable not only to understand many human disorders but also in regenerative medicine. Embryonic skeletogenesis is an excellent model to study this mechanism. Most cartilages share the cellular basis underlying chondrogenesis but the high heterogeneity in morphologies of the different skeletal elements appears to be generated by differential participation of a variety of chondrogenic signals. Here (...) we overview the regulatory factors responsible for chondrogenesis concluding that early chondrogenic signals for the digit cartilages differ from those implicated in the formation of other axial and appendicular skeletal components. BioEssays 29:725–737, 2007. © 2007 Wiley Periodicals, Inc. (shrink)