I suggest that the social justice issues raised by Internet regulation can be exposed and examined by using a methodology adapted from that described by John Rawls in 'A Theory of Justice'. Rawls' theory uses the hypothetical scenario of people deliberating about the justice of social institutions from the 'original position' as a method of removing bias in decision-making about justice. The original position imposes a 'veil of ignorance' that hides the particular circumstances of individuals from them so that they (...) will not be influenced by self-interest. I adapt Rawls' methodology by introducing an abstract description of information technology to those deliberating about justice from within the original position. This abstract description focuses on computing devices that users can use to access information and information networks that information devices use to communicate. The abstractness of this description prevents the particular characteristics of the Internet and the computing devices in use from influencing the decisions about the just use and regulation of information technology and networks. From this abstract position, the principles of justice that the participants accept for the rest of society will also apply to the computing devices people use to communicate, and to Internet regulation. (shrink)

The paper considers contemporary models of presumption in terms of their ability to contribute to a working theory of presumption for argumentation. Beginning with the Whatelian model, we consider its contemporary developments and alternatives, as proposed by Sidgwick, Kauffeld, Cronkhite, Rescher, Walton, Freeman, Ullmann-Margalit, and Hansen. Based on these accounts, we present a picture of presumptions characterized by their nature, function, foundation and force. On our account, presumption is a modal status that is attached to a claim and has the (...) effect of shifting, in a dialogue, a burden of proof set at a local level. Presumptions can be analysed and evaluated inferentially as components of rule-based structures. Presumptions are defeasible, and the force of a presumption is a function of its normative foundation. This picture seeks to provide a framework to guide the development of specific theories of presumption. (shrink)

Coronavirus disease 2019 can lead to respiratory failure. Some patients require extracorporeal membrane oxygenation support. During the current pandemic, health care resources in some cities have been overwhelmed, and doctors have faced complex decisions about resource allocation. We present a case in which a pediatric hospital caring for both children and adults seeks to establish guidelines for the use of extracorporeal membrane oxygenation if there are not enough resources to treat every patient. Experts in critical care, end-of-life care, bioethics, and (...) health policy discuss if age should guide rationing decisions. (shrink)

The coronavirus disease 2019 (COVID-19) pandemic has motivated medical ethicists and several task forces to revisit or issue new guidelines on allocating scarce medical resources. Such guidelines are relevant for the allocation of scarce therapeutics and vaccines and for allocation of ICU beds, ventilators, and other life-sustaining treatments or potentially scarce interventions. Principles underlying these guidelines, like saving the most lives, mitigating disparities, reciprocity to those who assume additional risk (eg, essential workers and clinical trial participants), and equal access may (...) compete with one another. We propose the use of a “categorized priority system” (also known as a “reserve system”) as an improvement over existing allocation methods, particularly because it may be able to achieve disparity mitigation better than other methods. (shrink)

: Two major philosophers of the twentieth century, the German existential phenomenologist Martin Heidegger and the seminal Japanese Kyoto School philosopher Nishida Kitarō are examined here in an attempt to discern to what extent their ideas may converge. Both are viewed as expressing, each through the lens of his own tradition, a world in transition with the rise of modernity in the West and its subsequent globalization. The popularity of Heidegger's thought among Japanese philosophers, despite its own admitted limitation to (...) the Western "history of being," is connected to Nishida's opening of a uniquely Japanese path in its confrontation with Western philosophy. The focus is primarily on their later works (the post-Kehre Heidegger and the works of Nishida that have been designated "Nishida philosophy"), in which each in his own way attempts to overcome the subject-object dichotomy inherited from the tradition of Western metaphysics by looking to a deeper structure from out of which both subjectivity and objectivity are derived and which embraces both. For Heidegger, the answer lies in being as the opening of unconcealment, from out of which beings emerge, and for Nishida, it is the place of nothingness within which beings are co-determined in their oppositions and relations. Concepts such as Nishida's "discontinuous continuity," "absolutely self-contradictory identity" (between one and many, whole and part, world and things), the mutual interdependence of individuals, and the self-determination of the world through the co-relative self-determination of individuals, and Heidegger's "simultaneity" (zugleich) and "within one another" (ineinander) (of unconcealment and concealment, presencing and absencing), and their "between" (Zwischen) and "jointure" (Fuge) are examined. Through a discussion of these ideas, the suggestion is made of a possible "transition" (Übergang) of both Western and Eastern thinking, in their mutual encounter, both in relation to each other and each in relation to its own past history, leading to both a self-discovery in the other and to a simultaneous self-reconstitution. (shrink)

Famous examples of conceivability arguments include (i) Descartes’ argument for mind-body dualism, (ii) Kripke's ‘modal argument’ against psychophysical identity theory, (iii) Chalmers’ ‘zombie argument’ against materialism, and (iv) modal versions of the ontological argument for theism. In this paper, we show that for any such conceivability argument, C, there is a corresponding ‘mirror argument’, M. M is deductively valid and has a conclusion that contradicts C's conclusion. Hence, a proponent of C—henceforth, a ‘conceivabilist’—can be warranted in holding that C's premises (...) are conjointly true only if she can find fault with one of M's premises. But M's premises are modelled on a pair of C's premises. The same reasoning that supports the latter supports the former. For this reason, a conceivabilist can repudiate M's premises only on pain of severely undermining C's premises. We conclude on this basis that all conceivability arguments, including each of (i)–(iv), are fallacious. (shrink)

During the past decades, the culture industries have multiplied media spectacles in novel spaces and sites, and spectacle itself is becoming one of the organizing principles of the economy, polity, society, and everyday life. An Internet-based economy has been developing hi-tech spectacle as a means of promotion, reproduction, and the circulation and selling of commodities, using multimedia and increasingly sophisticated technology to dazzle consumers. M edia culture proliferates ever more technologically sophisticated spectacles to seize audiences and augment their power and (...) profit. The forms of entertainment permeate news and information, and a tablodized infotainment culture is more and more popular. New multimedia that synthesize forms of radio, film, TV news and entertainment, and the mushrooming domain of cyberspace, become spectacles of technoculture, generating expanding sites of information and entertainment, while intensifying the spectacle-form of media culture. Political and social life is also shaped more and more by media spectacle. Social and political conflicts are increasingly played out on the screens of media culture, which display spectacles like sensational murder cases, terrorist bombings, celebrity and political sex scandals, and the explosive violence of everyday life. M edia culture not only takes up expanding moments of contemporary experience, but also provides ever more material for fantasy, dreaming, modeling thought and behavior, and constructing identities. Of course, there have been spectacles since premodern times. Classical Greece had its Olympics, thespian and poetry festivals, its public rhetorical battles, and bloody and violent wars. Ancient Rome had its public offerings of bread and circuses, its orgies, its titanic political battles, and the spectacle of Empire with parades and monuments for triumphant Caesars and their armies, extravaganzas put on display in the 2000 film Gladiator.. (shrink)

I argue that when determining whether an agent ought to perform an act, we should not hold fixed the fact that she’s going to form certain attitudes (and, here, I’m concerned with only reasons-responsive attitudes such as beliefs, desires, and intentions). For, as I argue, agents have, in the relevant sense, just as much control over which attitudes they form as which acts they perform. This is important because what effect an act will have on the world depends not only (...) on which acts the agent will simultaneously and subsequently perform, but also on which attitudes she will simultaneously and subsequently form. And this all leads me to adopt a new type of practical theory, which I call rational possibilism. On this theory, we first evaluate the entire set of things over which the agent exerts control, where this includes the formation of certain attitudes as well as the performance of certain acts. And, then, we evaluate individual acts as being permissible if and only if, and because, there is such a set that is itself permissible and that includes that act as a proper part. Importantly, this theory has two unusual features. First, it is not exclusively act-orientated, for it requires more from us than just the performance of certain voluntary acts. It requires, in addition, that we involuntarily form certain attitudes. Second, it is attitude-dependent in that it holds that which acts we’re required to perform depends on which attitudes we’re required to form. I then show how these two features can help us both to address certain puzzling cases of rational choice and to understand why most typical practical theories (utilitarianism, virtue ethics, rational egoism, Rossian deontology, etc.) are problematic. (shrink)

The performance of one option can entail the performance of another. For instance, I have the option of baking a pumpkin pie as well as the option of baking a pie, and the former entails the latter. Now, suppose that both of these options are permissible. This raises the issue of which, if either, is more fundamental than the other. Is baking a pie permissible because it’s permissible to perform some instance of pie-baking, such as pumpkin-pie baking? Or is baking (...) a pumpkin pie permissible because it’s permissible to bake a pie? Or are they equally fundamental, as they would be if they were both permissible because, say, they both have optimal consequences? The aim of this paper is to compare two alternative responses to this issue—omnism and maximalism—and to argue that the latter is preferable. Roughly speaking, maximalism is the view that only those options that are not entailed by any other option are to be assessed in terms of whether they have some right-making feature F (such as that of having optimal consequences), whereas omnism is the view that all options are to be assessed in terms of whether they are F. I argue that maximalism is preferable to omnism because it provides a more plausible solution to the problem of act versions and is not subject to any problems of its own. And if I’m right about maximalism’s being preferable to omnism, then most moral theories, which are all versions of omnism, need significant revision. (shrink)

Tropes is a systematic investigation into the metaphysics of properties, aiming to motivate and defend trope theory, and more specifically Natural Class Trope Nominalism (NCTN). Ehring’s book treats an impressive span of relevant positions, considerations, debates and objections with charity and clarity; it’s also a real page-turner, at least if one has (as I do) a taste for analytic twists and turns.

The idea that the brain is a representational organ has roots in the nineteenth century, when neurologists began drawing conclusions about what the brain represents from clinical and experimental studies. One of the earliest controversies surrounding representation in the brain was the “muscles versus movements” debate, which concerned whether the motor cortex represents complex movements or rather fractional components of movement. Prominent thinkers weighed in on each side: neurologists John Hughlings Jackson and F.M.R. Walshe in favor of complex movements, neurophysiologist (...) Charles Sherrington and neurosurgeon Wilder Penfield in favor of movement components. This essay examines these and other brain scientists’ evolving notions of representation during the first eighty years of the muscles versus movements debate (c. 1873–1954). Although participants agreed about many of the superficial features of representation, their inferences reveal deep-seated disagreements about its inferential role. Divergent epistemological commitments stoked conflicting conceptions of what representational attributions imply and what evidence supports them. (shrink)

In a new paper in recent issue of this journal (PSTJ), Prof. M. Pitkanen describes a solar system model inspired by spiral galaxies. While we appreciate his new approach, we find it lacks substantial discussion on the nature of vortices and chirality in galaxy. Therefore we submit a viewpoint that Gross-Pitaevskii model can be a more complete description of both solar system and also spiral galaxies, especially taking into account the nature of chirality and vortices in galaxies. In this article, (...) we also hope to bring out some correspondence among existing models, so we discuss shortly: the topological vortice approach, Burgers equation in the light of KAM theory, and the Cantorian Navier-Stokes approach. Of course, this short article is far from being complete. We hope further investigation can be done around this line of approach. Aim of this paper: With this article, we hope to begin a healthy dialogue with Prof. M. Pitkanen, especially on his solar system model, since we also believe that he also support “evidence-based physics.” Limitation: In this paper we only discuss Pitkanen’s solar system model, we don’t discuss his other papers in a recent issue of PSTJ. (shrink)

Collected and edited by Noah Levin -/- Table of Contents: -/- UNIT ONE: INTRODUCTION TO CONTEMPORARY ETHICS: TECHNOLOGY, AFFIRMATIVE ACTION, AND IMMIGRATION 1 The “Trolley Problem” and Self-Driving Cars: Your Car’s Moral Settings (Noah Levin) 2 What is Ethics and What Makes Something a Problem for Morality? (David Svolba) 3 Letter from the Birmingham City Jail (Martin Luther King, Jr) 4 A Defense of Affirmative Action (Noah Levin) 5 The Moral Issues of Immigration (B.M. Wooldridge) 6 The Ethics of our (...) Digital Selves (Noah Levin) -/- UNIT TWO: TORTURE, DEATH, AND THE “GREATER GOOD” 7 The Ethics of Torture (Martine Berenpas) 8 What Moral Obligations do we have (or not have) to Impoverished Peoples? (B.M. Wooldridge) 9 Euthanasia, or Mercy Killing (Nathan Nobis) 10 An Argument Against Capital Punishment (Noah Levin) 11 Common Arguments about Abortion (Nathan Nobis & Kristina Grob) 12 Better (Philosophical) Arguments about Abortion (Nathan Nobis & Kristina Grob) -/- UNIT THREE: PERSONS, AUTONOMY, THE ENVIRONMENT, AND RIGHTS 13 Animal Rights (Eduardo Salazar) 14 John Rawls and the “Veil of Ignorance” (Ben Davies) 15 Environmental Ethics: Climate Change (Jonathan Spelman) 16 Rape, Date Rape, and the “Affirmative Consent” Law in California (Noah Levin) 17 The Ethics of Pornography: Deliberating on a Modern Harm (Eduardo Salazar) 18 The Social Contract (Thomas Hobbes) -/- UNIT FOUR: HAPPINESS 19 Is Pleasure all that Matters? Thoughts on the “Experience Machine” (Prabhpal Singh) 20 Utilitarianism (J.S. Mill) 21 Utilitarianism: Pros and Cons (B.M. Wooldridge) 22 Existentialism, Genetic Engineering, and the Meaning of Life: The Fifths (Noah Levin) 23 The Solitude of the Self (Elizabeth Cady Stanton) 24 Game Theory, the Nash Equilibrium, and the Prisoner’s Dilemma (Douglas E. Hill) -/- UNIT FIVE: RELIGION, LAW, AND ABSOLUTE MORALITY 25 The Myth of Gyges and The Crito (Plato) 26 God, Morality, and Religion (Kristin Seemuth Whaley) 27 The Categorical Imperative (Immanuel Kant) 28 The Virtues (Aristotle) 29 Beyond Good and Evil (Friedrich Nietzsche) 30 Other Moral Theories: Subjectivism, Relativism, Emotivism, Intuitionism, etc. (Jan F. Jacko). (shrink)

Can new technology enhance purpose-driven, democratic dialogue in groups, governments, and societies? Online Deliberation: Design, Research, and Practice is the first book that attempts to sample the full range of work on online deliberation, forging new connections between academic research, technology designers, and practitioners. Since some of the most exciting innovations have occurred outside of traditional institutions, and those involved have often worked in relative isolation from each other, work in this growing field has often failed to reflect the full (...) set of perspectives on online deliberation. This volume is aimed at those working at the crossroads of information/communication technology and social science, and documents early findings in, and perspectives on, this new field by many of its pioneers. -/- CONTENTS: -/- Introduction: The Blossoming Field of Online Deliberation (Todd Davies, pp. 1-19) -/- Part I - Prospects for Online Civic Engagement -/- Chapter 1: Virtual Public Consultation: Prospects for Internet Deliberative Democracy (James S. Fishkin, pp. 23-35) -/- Chapter 2: Citizens Deliberating Online: Theory and Some Evidence (Vincent Price, pp. 37-58) -/- Chapter 3: Can Online Deliberation Improve Politics? Scientific Foundations for Success (Arthur Lupia, pp. 59-69) -/- Chapter 4: Deliberative Democracy, Online Discussion, and Project PICOLA (Public Informed Citizen Online Assembly) (Robert Cavalier with Miso Kim and Zachary Sam Zaiss, pp. 71-79) -/- Part II - Online Dialogue in the Wild -/- Chapter 5: Friends, Foes, and Fringe: Norms and Structure in Political Discussion Networks (John Kelly, Danyel Fisher, and Marc Smith, pp. 83-93) -/- Chapter 6: Searching the Net for Differences of Opinion (Warren Sack, John Kelly, and Michael Dale, pp. 95-104) -/- Chapter 7: Happy Accidents: Deliberation and Online Exposure to Opposing Views (Azi Lev-On and Bernard Manin, pp. 105-122) -/- Chapter 8: Rethinking Local Conversations on the Web (Sameer Ahuja, Manuel Pérez-Quiñones, and Andrea Kavanaugh, pp. 123-129) -/- Part III - Online Public Consultation -/- Chapter 9: Deliberation in E-Rulemaking? The Problem of Mass Participation (David Schlosberg, Steve Zavestoski, and Stuart Shulman, pp. 133-148) -/- Chapter 10: Turning GOLD into EPG: Lessons from Low-Tech Democratic Experimentalism for Electronic Rulemaking and Other Ventures in Cyberdemocracy (Peter M. Shane, pp. 149-162) -/- Chapter 11: Baudrillard and the Virtual Cow: Simulation Games and Citizen Participation (Hélène Michel and Dominique Kreziak, pp. 163-166) -/- Chapter 12: Using Web-Based Group Support Systems to Enhance Procedural Fairness in Administrative Decision Making in South Africa (Hossana Twinomurinzi and Jackie Phahlamohlaka, pp. 167-169) -/- Chapter 13: Citizen Participation Is Critical: An Example from Sweden (Tomas Ohlin, pp. 171-173) -/- Part IV - Online Deliberation in Organizations -/- Chapter 14: Online Deliberation in the Government of Canada: Organizing the Back Office (Elisabeth Richard, pp. 177-191) -/- Chapter 15: Political Action and Organization Building: An Internet-Based Engagement Model (Mark Cooper, pp. 193-202) -/- Chapter 16: Wiki Collaboration Within Political Parties: Benefits and Challenges (Kate Raynes-Goldie and David Fono, pp. 203-205) -/- Chapter 17: Debian’s Democracy (Gunnar Ristroph, pp. 207-211) -/- Chapter 18: Software Support for Face-to-Face Parliamentary Procedure (Dana Dahlstrom and Bayle Shanks, pp. 213-220) -/- Part V - Online Facilitation -/- Chapter 19: Deliberation on the Net: Lessons from a Field Experiment (June Woong Rhee and Eun-mee Kim, pp. 223-232) -/- Chapter 20: The Role of the Moderator: Problems and Possibilities for Government-Run Online Discussion Forums (Scott Wright, pp. 233-242) -/- Chapter 21: Silencing the Clatter: Removing Anonymity from a Corporate Online Community (Gilly Leshed, pp. 243-251) -/- Chapter 22: Facilitation and Inclusive Deliberation (Matthias Trénel, pp. 253-257) -/- Chapter 23: Rethinking the ‘Informed’ Participant: Precautions and Recommendations for the Design of Online Deliberation (Kevin S. Ramsey and Matthew W. Wilson, pp. 259-267) -/- Chapter 24: PerlNomic: Rule Making and Enforcement in Digital Shared Spaces (Mark E. Phair and Adam Bliss, pp. 269-271) -/- Part VI - Design of Deliberation Tools -/- Chapter 25: An Online Environment for Democratic Deliberation: Motivations, Principles, and Design (Todd Davies, Brendan O’Connor, Alex Cochran, Jonathan J. Effrat, Andrew Parker, Benjamin Newman, and Aaron Tam, pp. 275-292) -/- Chapter 26: Online Civic Deliberation with E-Liberate (Douglas Schuler, pp. 293-302) -/- Chapter 27: Parliament: A Module for Parliamentary Procedure Software (Bayle Shanks and Dana Dahlstrom, pp. 303-307) -/- Chapter 28: Decision Structure: A New Approach to Three Problems in Deliberation (Raymond J. Pingree, pp. 309-316) -/- Chapter 29: Design Requirements of Argument Mapping Software for Teaching Deliberation (Matthew W. Easterday, Jordan S. Kanarek, and Maralee Harrell, pp. 317-323) -/- Chapter 30: Email-Embedded Voting with eVote/Clerk (Marilyn Davis, pp. 325-327) -/- Epilogue: Understanding Diversity in the Field of Online Deliberation (Seeta Peña Gangadharan, pp. 329-358). -/- For individual chapter downloads, go to odbook.stanford.edu. (shrink)

Emphasizing the human body in all of its forms, Beauty Unlimited expands the boundaries of what is meant by beauty both geographically and aesthetically. Peg Zeglin Brand and an international group of contributors interrogate the body and the meaning of physical beauty in this multidisciplinary volume. This striking and provocative book explores the history of bodily beautification; the physicality of socially or culturally determined choices of beautification; the interplay of gender, race, class, age, sexuality, and ethnicity within and on the (...) body; and the aesthetic meaning of the concept of beauty in an increasingly globalized world. Foreward by Carolyn Korsmeyer. Authors include Noel Carroll, Gregory Velazco Y Trianosky, Monique Roelofs, Whitney Davis, Eleanor Heartney, Diana Tietjens Meyers, Phoebe M. Farris, Mary Devereaux, Jo Ellen Jacobs, Karina L. Cespedes-Cortes and Paul C. Taylor, Fedwa Malti-Douglas, Stephen Davies, Jane Duran, Valerie Sullivan Fuchs, Keith Lehrer, Allen Douglas, Cynthia Freeland, Eva Kit Wah Man, Mary Bittner Wiseman, and Peg Brand's essay, "ORLAN Revisited: Disembodied Virtual Hybrid Beauty.". (shrink)

OBJETIVO -/- O estudante de Zootecnia e de Veterinária, quando se depara com a produção animal, um dos pilares importantes é a reprodução, uma vez que é a perpetuação da espécie, seja para gerar filhas de uma vaca campeã em produção leiteira e de um touro com rusticidade e com aptidão produtiva de corte, ou mesmo para reposição de um plantel, o mesmo deve estar consciente de que esse ramo é de extrema responsabilidade, já que estará intimamente lidando com a (...) vida e com um investimento que pode gerar lucros em demasia para a propriedade ou, se mal feito o manejo da reprodução, trazer sérios transtornos para a mesma. -/- Nesse trabalho, o estudante revisará os sucessos da puberdade e estacionalidade reprodutiva relacionando-os com os processos endócrinos e os fatores que afetam sua manifestação como os nutricionais, para compreender a maneira ao qual podem ser manipuladas. -/- -/- • _____INTRODUÇÃO -/- A puberdade marca o início da vida reprodutiva do animal, permitindo integrar o indivíduo ao seu ciclo produtivo. A estacionalidade é uma característica de adaptação que algumas espécies desenvolveram para fazer garantir a eficiência da reprodução e a sobrevivência dos filhotes. -/- -/- • _____PUBERDADE -/- A puberdade é atingida quando o animal é capaz de produzir e liberar gametas viáveis e funcionais (férteis). Na fêmea esse fato ocorre na primeira ovulação, que geralmente coincide com a manifestação do comportamento do cio; e nos machos durante a primeira ejaculação com espermatozoides viáveis. -/- Do ponto de vista da produção animal, puberdade prematura ou precoce, é importante para poder permitir a incorporação dos animais ao ciclo produtivo o mais rapidamente possível. No caso de touros holandeses, por exemplo, é desejável que produzam sêmen precocemente para incorporá-los a prova de progênie; nas fêmeas, entretanto, deve-se considerar que nem sempre é conveniente usar o primeiro ciclo ou cio para reprodução. É o caso das marrãs (porcas primíparas), onde é benéfico esperar até o segundo ou terceiro estro para aumentar o tamanho da ninhada. Também pode ser vantajoso esperar que o indivíduo alcance sua maturidade sexual, que ocorre quando a fêmea consegue se reproduzir sem sofrer efeitos adversos. A ovelha nascida na primavera, por exemplo, pode engravidar no outono seguinte e dar à luz no primeiro ano de vida, mas seu crescimento pode ser afetado; o mesmo ocorre com a novilha, em que o acasalamento precoce pode promover distorcia por falta de desenvolvimento pélvico. -/- A puberdade é um processo gradual e está intimamente relacionada à taxa de crescimento e ao metabolismo energético. O recém-nascido usa energia para funções vitais, principalmente termorregulação; esse feito se deve ao fato de os jovens possuírem uma superfície corporal muito elevada em relação ao seu volume. Durante o desenvolvi-mento subsequente dos tecidos também há prioridade no uso de nutrientes, que inicialmente favorecem o desenvolvimento do tecido ósseo e muscular, e uma vez que estes atingem determinado tamanho de acordo com as condições genéticas do indivíduo, inicia-se o desenvolvimento do tecido adiposo, que é indicativa de um reservatório de energia. É importante ressaltar que existe uma interação entre a genética e o meio ambiente, de forma que o potencial genético só será expresso se o meio ambiente for favorável. -/- Para que a ovulação ocorra, é necessário considerar o funcionamento do eixo hipotálamo-hipófise-gonodal. O aumento da frequência pulsátil do GnRH hipotalâmico e em consequência do LH hipofisário provoca a maturação do folículo em nível gonodal, o que aumenta a produção de estrógenos. O aumento dos estrogênios causa, por feedback positivo no hipotálamo, a liberação do pico pré-ovulatório de LH e, consequentemente, a ovulação. Na fase pré-púbere, a frequência dos pulsos de GnRH e LH é muito baixa e insuficiente para provocar a maturação folicular, pois o hipotálamo é inibido e, portanto, não ocorre ovulação. -/- A geração pulsátil de GnRH no momento reprodutivo adequado para desencadear o início da puberdade depende de uma rede neural complexa que, além dos neurônios GnRH, inclui outros neurônios e células da glia; ele também integra vários sinais internos e externos para o corpo. A morfologia dos neurônios GnRH também é única, uma vez que seus dendritos também podem funcionar como axônios, dando-lhes uma função distinta. A geração de pulsos também indica a necessidade de sincronização entre subpopulações de neurônios GnRH, que, acima de tudo, parece ser extrínseca a esses neurônios e envolve múltiplos hormônios e neurotransmissores -/- Se dois níveis de conexões aferentes são considerados, estima-se que cada neurônio de GnRH pode ser conectado a cerca de cinco milhões de outros neurônios; milhares de genes, então, podem estar envolvidos no processo da puberdade. A importância funcional e hierárquica de cada um desses genes no controle dos neurônios GnRH, juntamente com outros fatores neuronais e gliais, pode diferir entre as espécies. Existem, no entanto, componentes fundamentais que parecem ser comuns a todos os mamíferos e que se situam nos níveis hierárquicos mais elevados, ajudando a compreender a progressão do processo puberal. Assim, todas as espécies de mamíferos estudadas, por exemplo, têm aglomerados de neurônios kisspeptinérgicos (que secretam kisspeptina), envolvidos na regulação da secreção tônica e secreção cíclica de GnRH, que também se classifica como o elemento mais alto na hierarquia desse complexo neuronal após considerar os neurônios GnRH. -/- Sabe-se que o eixo hipotálamo-hipofisário-gonodal está ativo desde as primeiras fases da vida do indivíduo, mesmo antes do nascimento em certas espécies. A secreção de GnRH, no entanto, é suprimida mais tarde no desenvolvimento e permanece dessa forma até o período pré-púbere, quando será reativada gradualmente. -/- Por várias décadas, a supressão e reinicialização dos pulsos de GnRH foi atribuída a uma hipótese conhecida como teoria gonadostat que afirma que o centro tônico do hipotálamo é inibido devido à sua sensibilidade ao mecanismo de feedback negativo dos esteroides gonodais, é aumentado; portanto, o GnRH e a consequente secreção de gonadotrofinas (FSH e LH) são insuficientes para a ocorrência da maturação folicular e espermatogênese. Essa sensibilidade diminui progressivamente à medida que a puberdade se aproxima. -/- Sabe-se agora que existem fatores não gonodais que agem em paralelo com os esteroides para mediar mudanças no feedback negativo que também são específicos da espécie. -/- Na fêmea, o centro gerador de pulso cíclico também deve ser considerado, o qual é responsável por iniciar a primeira ovulação. O centro cíclico é composto por uma segunda subpopulação de neurônios GnRH que é reativada por meio de uma complexa interação entre vários sistemas neuronais inibitórios (que devem reduzir progressiva-mente sua influência) e outros sistemas excitatórios, que, por sua vez, operam por meio de diferentes neurotransmissores, como o ácido γ-amino-butírico (GABA) e seus receptores, glutamato, óxido nítrico e neuropeptídio Y (NPY). Esses fatores, juntamente com as alterações morfológicas observadas nos neurônios do GnRH à medida que a puberdade se aproxima, e com as interações e sinais aferentes das células gliais, levam a um padrão de progressão linear que culminará na reativação do centro cíclico. Esse processo era conhecido anteriormente como teoria da maturação central e faz parte das mudanças que configuram o processo para chegar à puberdade. A elevação nas concen-trações de estradiol subsequente à reativação gradual do centro gerador de pulso tônico GnRH provavelmente permitirá a maturação final do centro cíclico. -/- A forma como cada organismo estabelece o momento certo para iniciar as mudanças que levam à puberdade é conhecido; a existência de algum mecanismo neurobiológico que constitui um relógio interno pode ser considerada. No entanto, esse mecanismo afetaria principalmente o desenvolvimento neuronal no nível central; também seria difícil compará-lo com a maneira pela qual fatores externos ao indivíduo afetam o início da puberdade. Nessa perspectiva, um sistema que permita receber informações completas sobre o crescimento e desenvolvimento do indivíduo poderia ser mais prático. Os mediadores desse sistema incluem o hormônio do crescimento, IGF-I, leptina e outros substratos metabólicos. A leptina em particular, que sinaliza as reservas de tecido adiposo, é um dos elementos mais importantes e, embora não determine quando começa a puberdade, se atua como fator permissivo para que o processo progrida, uma vez que excede um nível limite. A consideração do estágio de desenvolvimento do animal para o início da puberdade era anteriormente conhecida como o peso corporal crítico ou teoria do lipostato. É importante considerar que as três teorias mencionadas não são exclusivas. -/- O mecanismo da puberdade nos machos é semelhante ao já descrito; entretanto, deve-se lembrar que no macho o centro cíclico não está ativo. À medida que a puberdade se aproxima, o crescimento testicular é desencadeado e, em ruminantes e suínos, o pênis que estava preso à mucosa prepucial é gradualmente liberado. -/- -/- • _____FATORES QUE INFLUENCIAM A PUBERDADE -/- Os animais podem manifestar a puberdade de três formas diferentes. Pode ser tardia e o animal demorar para estar apto a reprodução; precoce e o animal entrar na vida reprodutiva antes do esperado ou pode ser normal e o animal estar com boa conformação e idade. Para tanto, alguns fatores podem interferir à manifestação da puberdade pelos animais como a genética, idade e peso, nutrição, fotoperíodo e o próprio manejo adotado. -/- -/- Genética -/- O genótipo afeta a idade da puberdade, pois algumas raças são anteriores a outras. Nos bovinos, as raças europeias atingem a puberdade antes dos zebuínos, isto é, uma novilha ou novilho da raça holandesa atinge a puberdade primeiro que os animais da mesma idade e do mesmo peso da raça nelore, por exemplo. -/- Da mesma forma, as porcas da raça chinesa Meishan atingem a puberdade por volta dos 115 dias de idade, metade da idade das raças brancas. As ovelhas de raças de corte, da mesma forma, são mais precoces que os produtores de lã. As raças pequenas, da mesma forma, são geralmente mais precoces, pelo menos em bovinos (jersey x guzerá) e em caninos. Os híbridos, por outro lado, apresentam puberdade mais precoce que os puros, devido ao efeito da heterose. Por este motivo, em certas espécies são utilizadas linhas híbridas. -/- -/- Idade e peso -/- A tabela 1 mostra a idade média de início da puberdade em espécies domésticas. O peso vivo (PV) adulto é mais relevante para a idade na puberdade nos ruminantes, enquanto em suínos é menos decisivo. A tabela também apresenta a porcentagem de peso corporal necessária para a puberdade ocorrer de forma natural. -/- -/- Tabela 1: Idade e peso a puberdade das espécies domésticas -/- Espécie -/- Fêmea (meses) -/- Macho (meses) -/- PV adulto (%) -/- Gado holandês -/- 11 (8-15) -/- 11 (7-18) -/- 30-40 -/- Gado brahman -/- 19 -/- 17 -/- 45-60 -/- Caprinos e ovinos -/- 7 (4-14) -/- 7 (6-9) -/- 40-60 -/- Suínos -/- 6 (5-7) -/- 7 (5-8) -/- 75 -/- Equinos -/- 18 (12-19) -/- 14 (10-24) -/- - -/- Caninos -/- 12 (6-24) -/- 9 (5-12) -/- - -/- Felinos -/- 8 (4-12) -/- 9 (8-10) -/- - -/- Fonte: VALENCIA, 2018. -/- Nutrição -/- Como a puberdade está relacionada à taxa de crescimento, os animais que recebem uma nutrição adequada e balanceada apresentarão puberdade em uma idade mais jovem, ou seja, mais precocemente; ao contrário, a puberdade será tardia nos animais que sofreram restrição alimentar, que estão desnutridos ou que tiveram seu crescimento afetado por doenças infecciosas ou parasitárias. A superalimentação também não é recomendada, pois pode alterar tanto os sinais que são recebidos pelo hipotálamo quanto sua resposta a eles. -/- Logo, o manejo alimentar adotado deve estar de acordo com as normas estabeleci-das pelos especialistas na área, principalmente no tocante as exigências nutricionais que devem servir de regra na propriedade. Sendo assim, os animais entrarão em puberdade com as taxas de alta qualidade o que afetará positivamente na prole futura e dará retorno lucrativo ao proprietário. -/- -/- Época do ano (Fotoperíodo) -/- Em fêmeas de espécies sazonais, como ovelhas e cabras, existem certos requisitos de fotoperíodo que devem ser atendidos para que a puberdade ocorra. Nessas espécies, um período de exposição a dias longos é necessário, seguido por outro de exposição a dias curtos. Na verdade, os cordeiros e cabritos nascidos fora da estação, mesmo que tenham atingido o peso necessário, terão que esperar até o outono seguinte (a estação reprodutiva) para atingir a puberdade. Os machos, por outro lado, não estão sujeitos a essas limitações nos requisitos fotoperiódicos para apresentar a puberdade. -/- Em novilhas nascidas no outono, por outro lado, a puberdade ocorre antes de um ano de idade, no verão seguinte ou no início do outono, mais cedo do que nas nascidas na primavera, devido à exposição a longos dias durante os primeiros seis meses do ano após seu nascimento aceleram seu crescimento. Em gatos, o aumento do fotoperíodo também acelera o início da puberdade. -/- Em ovelhas e novilhas, a primeira ovulação que ocorre ao entrar na puberdade é silenciosa; ou seja, não é acompanhada de sinais comportamentais de cio como a micção frequente, inchamento da vulva, uma montando a outra e deixando-se montar etc., pois para que esse comportamento se manifeste, o sistema nervoso necessita de uma pré-sensibilização com progesterona que não estará presente até o próximo ciclo, após o desenvolvimento do corpo lúteo vindo desta primeira ovulação. -/- -/- Sociossexual -/- A interação de indivíduos da mesma espécie ou a presença ou ausência de sinais de bioestimulação, como feromônios, pode afetar o período de puberdade. A puberdade, por exemplo, é atrasada em porcas criadas individualmente em comparação com porcas criadas em grupo. Além disso, na porca, ovelha e cabra, a exposição ao macho estimula as fêmeas e a puberdade aparece mais precocemente. -/- -/- Manejo -/- Certas práticas de manejo podem acelerar a puberdade, especialmente no período pré-púbere. Em porcas próximas à puberdade, por exemplo, o estresse causado por procedimentos, como o transporte de um local para outro ou a exposição ao macho, faz com que apareça o estro em torno de sete dias após a realização do manejo mencionado. -/- -/- • _____ESTACIONALIDADE REPRODUTIVA -/- A estacionalidade ou sazonalidade reprodutiva é uma estratégia evolutiva que se desenvolveu em algumas espécies; tende a tornar a reprodução mais eficiente. Nos países de latitudes distantes do equador, o objetivo é que as crias nasçam na primavera, época do ano mais favorável, graças à abundância de alimentos e às amenas condições climáticas. No caso da ovelha, cuja gestação dura cinco meses, para que os partos ocorram na primavera, ela deve engravidar no outono (figura 1), quando os dias são curtos; enquanto a égua, tendo uma gestação de aproximadamente 11 meses, deve conceber na primavera, quando os dias são longos; assim, o parto ocorrerá na primavera do ano seguinte (figura 2). -/- -/- Figura 1: Esquema ilustrativo da estacionalidade reprodutiva na espécie ovina. Fonte: PIRES et al., 2011. -/- -/- Esta característica evolutiva desenvolvida pela seleção natural na maioria das espécies silvestres e ainda é conservado por algumas espécies domésticas, como ovelhas, cabras, cavalos e gatos. Em bovinos e suínos, ao contrário, a domesticação levou à perda quase total da estacionalidade reprodutiva. -/- A estacionalidade reprodutiva é codificada nos genes; significa então que a seleção natural favoreceu a propagação de genes que permitiam acoplar a hora do nascimento com a melhor época do ano, por isso passou a ser considerada um método anticoncepcional natural. -/- -/- Figura 2: ciclo reprodutivo anual em espécies estacionais; onde são apresentados os períodos de gestação e a forma como se agrupam os nascimentos, independentemente da época reprodutiva da espécie, em vermelho as fêmeas estão apresentando estro ou cio. Fonte: VALENCIA, 2018. -/- -/- Fotoperíodo -/- Para sincronizar o período fértil com a época mais favorável do ano, a maioria das espécies sazonais usa o fotoperíodo (quantidade de luz diária ao longo do ano). -/- Este sinal ambiental é seguro, confiável e se repete a cada ano. Ovinos e caprinos se reproduzem na época do ano em que os dias são curtos e os equinos quando são longos. O grau de sazonalidade depende da origem da raça. As raças nativas de países localizados em latitudes elevadas (> 50°,ovelhas: soay, blackface, suffolk; cabras: saanen, alpino francês, toggenburg; equinos: puro-sangue, hanoveriano) terão uma estacionalidade mais acentuada do que as latitudes menores ou mediterrâneas (ovelhas: merino; cabras: murciana granadina; equinos: quarto de milha). Também existem raças de latitudes próximas ao Equador cuja estacionalidade é baixa ou nula (ovelhas: raças de pelo, crioulas; cabras: raças africanas e asiáticas) (tabela 2). -/- Para a maioria das raças de ovinos e caprinos, a estação reprodutiva começa no final do verão e início do outono; caracteriza-se pela apresentação de ciclos estrais sucessivos, e termina no final do inverno, quando se inicia o anestro, que se caracteriza pela ausência de ovulação. Nos equinos, ocorre o contrário, uma vez que a estação reprodutiva ocorre na primavera e no verão. -/- -/- Tabela 2: Relação entre a origem da raça e o grau de estacionalidade ou sazonalidade -/- Espécie -/- Alta -/- Média -/- Baixa -/- Ovinos -/- Suffolk, raças britânicas de lã e corte -/- Merino -/- Pelibuey, crioulas -/- Caprinos -/- Saanen, alpino, toggenburg -/- Murciana granadina -/- Crioula -/- Equinos -/- Puro-sangue, hanoveriano, quarto de milha -/- - -/- Crioula, burros -/- Fonte: VALENCIA, 2018. -/- -/- Mecanismo neuroendócrino da estacionalidade -/- Durante o período de anestro, o fotoperíodo exerce efeito inibitório sobre o centro tônico do GnRH no hipotálamo, diminuindo a frequência de pulso. Consequentemente, a pulsatilidade do LH também diminui, que agora é incapaz de induzir a maturação folicular, o aumento dos estrogênios, o pico pré-ovulatório de LH e, portanto, a ovulação. -/- Isso ocorre porque durante o anestro a sensibilidade do hipotálamo ao mecanismo de feedback negativo dos estrogênios e de outros fatores de origem não gonodal é aumentada. Ao aproximar-se da estação reprodutiva, a sensibilidade hipotalâmica diminui e o aumento da pulsatilidade do GnRH causa as mudanças que culminam na ovulação. Portanto, o mecanismo endócrino do anestro estacional é semelhante ao do anestro pré-púbere e de alguns outros tipos de anestro. -/- A estacionalidade é um bom exemplo da interação entre o meio ambiente e o sistema neuroendócrino, pois o organismo é capaz de traduzir um sinal externo ambiental, como o fotoperíodo, em um sinal hormonal interno, que neste caso é a melatonina. -/- A glândula pineal secreta melatonina durante as horas de escuridão. Os animais sazonais apresentam um ritmo reprodutivo endógeno, que é regulado por janelas de fotossensibilidade, determinadas por mudanças na duração do dia. O sinal luminoso é captado pela retina e conduzido, via nervo, pelo trato retino-hipotalâmico até o núcleo supraquiasmático, que funciona como o relógio biológico do corpo. Daí o sinal viaja para o núcleo para-ventricular, depois para o gânglio cervical e, finalmente, para a glândula pineal, que responde secretando melatonina (figura 3). -/- Nas ovelhas, a estação reprodutiva começa quando a duração do dia diminui e, naturalmente, a noite aumenta; na égua, ocorre quando os dias se alongam. -/- A primavera não é necessariamente a melhor época do ano em todas as regiões do globo. Nas latitudes tropicais, a primavera coincide com a seca e não com a abundância de forragem, aspecto a ser levado em consideração ao programar a reprodução. -/- Outro ponto importante a considerar é que as raças europeias sazonais mantêm sua estacionalidade no Brasil. -/- -/- Figura 3: Mecanismo do fotoperíodo em ovinos e a melatonina. Fonte: HAFEZ, 2004. -/- -/- Estacionalidade no macho -/- O macho é menos afetado que a fêmea pelas mudanças típicas de cada época do ano, já que sua função reprodutiva não é necessariamente interrompida durante o anestro ou repouso sexual, embora a produção de hormônios reprodutivos, tamanho e tônus testicular, a libido, as características qualitativas e quantitativas do ejaculado e a fertilidade do esperma podem ser diminuídas. O nível de afetação depende do grau de sazonalidade da raça e da latitude. Por fim, os efeitos do fotoperíodo devem ser separados dos nutricionais, que também variam com a época do ano. -/- -/- REFERÊNCIAS BIBLIOGRÁFICAS -/- -/- BEARDEN, Henry Joe et al. Reproducción animal aplicada. México: Manual Moderno, 1982. -/- BROOKS, P. H.; COLE, D. J. A. The effect of the presence of a boar on the attainment of puberty in gilts. Reproduction, v. 23, n. 3, p. 435-440, 1970. -/- CARDOSO, Daniel; DE PAULA NOGUEIRA, Guilherme. Mecanismos neuroendócrinos envolvidos na puberdade de novilhas. Arquivos de Ciências Veterinárias e Zoologia da Unipar, v. 10, n. 1, 2007. -/- CHEMINEAU, P. et al. Induction and persistence of pituitary and ovarian activity in the out-of-season lactating dairy goat after a treatment combining a skeleton photoperiod, melatonin and the male effect. Reproduction, v. 78, n. 2, p. 497-504, 1986. -/- CLARKE, Iain J. et al. Kisspeptin and seasonality in sheep. Peptides, v. 30, n. 1, p. 154-163, 2009. -/- CORTEEL, J. M. Production, storage and insemination of goat semen. In: Management and Reproduction in Sheep and Goats Symposium, Madison, Wis. (USA), 1977. University of Wisconsin, 1977. -/- CUNNINGHAM, James. Tratado de fisiologia veterinária. Elsevier Health Sciences, 2011. -/- CUPPS, Perry T. (Ed.). Reproduction in domestic animals. Elsevier, 1991. -/- DUKES, Henry Hugh; SWENSON, Melvin J.; REECE, William O. Dukes fisiologia dos animais domésticos. Editora Guanabara Koogan, 1996. -/- DÝRMUNDSSON, Ó. R.; LEES, J. L. Effect of rams on the onset of breeding activity in Clun Forest ewe lambs. The Journal of Agricultural Science, v. 79, n. 2, p. 269-271, 1972. -/- EBLING, F. J. P.; FOSTER, D. L. Photoperiod requirements for puberty differ from those for the onset of the adult breeding season in female sheep. Reproduction, v. 84, n. 1, p. 283-293, 1988. -/- FIELDS, Michael J.; SAND, Robert S.; YELICH, Joel V. (Ed.). Factors affecting calf crop: Biotechnology of reproduction. CRC Press, 2001. -/- HAFEZ, Elsayed Saad Eldin; HAFEZ, Bahaa. Reprodução animal. São Paulo: Manole, 2004. -/- HUGHES, P. E.; PHILIP, G.; SISWADI, R. The effects of contact frequency and transport on the efficacy of the boar effect. Animal Reproduction Science, v. 46, n. 1-2, p. 159-165, 1997. -/- KARSCH, FRED J. et al. Neuroendocrine basis of seasonal reproduction. In: Proceedings of the 1983 Laurentian Hormone Conference. Academic Press, 1984. p. 185-232. -/- LINCOLN, G. A.; SHORT, R. V. Seasonal breeding: nature's contraceptive. In: Proceedings of the 1979 Laurentian Hormone Conference. Academic Press, 1980. p. 1-52. -/- MELLO, Raquel Rodrigues Costa. Puberdade e maturidade sexual em touros bovinos. Agropecuária Científica no Semiárido, v. 10, n. 3, p. 11-28, 2015. -/- MEZA‐HERRERA, C. A. et al. Neuroendocrine, metabolic and genomic cues signalling the onset of puberty in females. Reproduction in Domestic Animals, v. 45, n. 6, p. e495-e502, 2010. -/- MONTEIRO, Claudia Dias; BICUDO, Sony Dimas; TOMA, Hugo Shisei. Puberdade em fêmeas ovinas. Pubvet, v. 4, p. Art. 850-857, 2010. -/- OLIVEIRA, Daniel de Jesus Cardoso de. Mecanismos neuroendócrinos envolvidos na puberdade de novilhas da raça Nelore. 2006. Tese de Doutorado em Medicina Veterinária. Universidade de São Paulo. -/- OLSTER, DEBORAH H.; FOSTER, DOUGLAS L. Control of gonadotropin secretion in the male during puberty: a decrease in response to steroid inhibitory feedback in the absence of an increase in steroid-independent drive in the sheep. Endocrinology, v. 118, n. 6, p. 2225-2234, 1986. -/- PIRES, Bruno Carlos et al. Métodos para elevar o ritmo reprodutivo dos ovinos. PUBVET, Londrina, V. 5, N. 11, Ed. 158, Art. 1071, 2011. -/- PLANT, Tony M.; ZELEZNIK, Anthony J. (Ed.). Knobil and Neill's physiology of reproduction. New York: Academic Press, 2014. -/- RAMIREZ, Domingo V.; MCCANN, S. M. Comparison of the regulation of luteinizing hormone (LH) secretion in immature and adult rats. Endocrinology, v. 72, n. 3, p. 452-464, 1963. -/- ROSER, JANET F.; HUGHES, JOHN P. Seasonal effects on seminal quality, plasma hormone concentrations, and GnRH‐induced LH response in fertile and subfertile stallions. Journal of andrology, v. 13, n. 3, p. 214-223, 1992. -/- SALOMONI, Eduardo et al. Idade e peso à puberdade em fêmeas de corte puras e cruzas em campo natural. Pesquisa Agropecuária Brasileira, v. 23, n. 10, p. 1171-1179, 1988. -/- SMITH, Jeremy T.; CLARKE, Iain J. Seasonal breeding as a neuroendocrine model for puberty in sheep. Molecular and cellular endocrinology, v. 324, n. 1-2, p. 102-109, 2010. -/- VALENCIA, J. Pubertad y estacionalidad reproductiva. In. PORTA, L. R.; MEDRANO, J. H. H. Fisiología reproductiva de los animales domésticos. Cidade do México: FMVZ-UNAM, 2018. -/- WHITTEMORE, Colin et al. The science and practice of pig production. Blackwell Science Ltd, 1998. -/- -/- -/- FIXAÇÃO DO ASSUNTO -/- -/- 1. Defina o que é puberdade e como ela manifesta-se no corpo. -/- -/- -/- 2. Diferencie puberdade de maturidade sexual. -/- -/- -/- 3. Quais são os fenômenos que devem ser observados em fêmeas que estão entrando na puberdade? -/- -/- -/- 4. Qual o papel do GnRH e do IGF-I sobre a puberdade? -/- 5. Um produtor possui duas ovelhas e um carneiro reprodutor, as ovelhas possuem idade e peso, mas não manifestaram seu primeiro cio, quais elementos que você recomenda ao produtor para induzir a ciclicidade dessas fêmeas? -/- -/- -/- 6. De forma geral, quais os fatores que podem afetar a entrada na puberdade dos animais? -/- -/- -/- 7. Defina estacionalidade reprodutiva. -/- -/- -/- 8. O que é fotoperíodo e qual sua importância para a reprodução dos animais domésticos? -/- -/- -/- 9. Defina as relações existentes entre a origem da raça e o grau de estacionalidade e como tais teorias se aplicam ao rebanho brasileiro. -/- -/- -/- 10. Qual o papel da glândula pineal para a estacionalidade reprodutiva? -/- -/- -/- 11. Por que os machos são menos afetados pela sazonalidade reprodutiva do que as fêmeas? -/- -/- -/- 12. Sabendo-se sobre os termos de puberdade e estacionalidade e as características de ambos nas espécies domésticas, pede-se: um criador deseja obter 5 novas crias ovinas e 5 caprinas em seu plantel até o final do ano, para tanto ele ainda possui um ano e está na estação do verão, sabendo-se sobre a estacionalidade dessas espécies elabore um projeto reprodutivo de modo que essas 10 fêmeas possam gerar uma cria cada até a primavera. -/- -/- Dados: 10 fêmeas gerando 10 crias. 1 macho ovino e 1 caprino. Fêmeas com 1 ano de idade (2º cio) e peso corporal = 55% do peso adulto. Verão de 2020 para parir na primavera de 2020. (shrink)

This paper argues that, by construing emotion as epistemologically subversive, the Western tradition has tended to obscure the vital role of emotion in the construction of knowledge. The paper begins with an account of emotion that stresses its active, voluntary, and socially constructed aspects, and indicates how emotion is involved in evaluation and observation. It then moves on to show how the myth of dispassionate investigation has functioned historically to undermine the epistemic authority of women as well as other social (...) groups associated culturally with emotion. Finally, the paper sketches some ways in which the emotions of underclass groups, especially women, may contribute to the development of a critical social theory. (shrink)

Perception is typically distinguished from cognition. For example, seeing is importantly different from believing. And while what one sees clearly influences what one thinks, it is debatable whether what one believes and otherwise thinks can influence, in some direct and non-trivial way, what one sees. The latter possible relation is the cognitive penetration of perception. Cognitive penetration, if it occurs, has implications for philosophy of science, epistemology, philosophy of mind, and cognitive science. This paper offers an analysis of the phenomenon, (...) its theoretical consequences, and a variety of experimental results and possible interpretations of them. The paper concludes by proposing some constraints for analyses and definitions of cognitive penetrability. (shrink)

Empirical philosophers of science aim to base their philosophical theories on observations of scientific practice. But since there is far too much science to observe it all, how can we form and test hypotheses about science that are sufficiently rigorous and broad in scope, while avoiding the pitfalls of bias and subjectivity in our methods? Part of the answer, we claim, lies in the computational tools of the digital humanities, which allow us to analyze large volumes of scientific literature. Here (...) we advocate for the use of these methods by addressing a number of large-scale, justificatory concerns—specifically, about the epistemic value of journal articles as evidence for what happens elsewhere in science, and about the ability of DH tools to extract this evidence. Far from ignoring the gap between scientific literature and the rest of scientific practice, effective use of DH tools requires critical reflection about these relationships. (shrink)

This chapter has four parts. I distinguishes some types of perceptual skills and highlights their importance in everyday perception. II identifies a well-studied class of perceptual skills: cases of perceptual expertise. III discusses a less studied possible instance of perceptual skill: picture perception. Finally, IV outlines some important mechanisms underlying perceptual skills, with special emphasis on attention and mental imagery.

Are living organisms--as Descartes argued--just machines? Or is the nature of life such that it can never be fully explained by mechanistic models? In this thought-provoking and controversial book, eminent geophysicist Walter M. Elsasser argues that the behavior of living organisms cannot be reduced to physico-chemical causality. Suggesting that molecular biology today is at the same point as Newtonian physics on the eve of the quantum revolution, Elsasser lays the foundation for a theoretical biology that points the way toward a (...) natural philosophy of organic life. Explicitly repudiating "vitalism" (the notion that the laws of nature need to be modified when applied to living organisms), Elsasser argues instead that the structural complexity of even a single living cell is "transcomputational"--that is, beyond the power of any imaginable system to compute. Beginning from this insight, Elsasser leads the reader through a step-by-step process that ultimately arrives at the conclusion that living and non-living matter are separated by "a no-man's land of irrationality." Trained in Germany as a physicist, Elsasser first pondered the implications of quantum mechanics for biology as early as 1951. The more closely he studied the inherent complexity of life, the more skeptical he became of the reductionist view of organisms as tiny machines. "An organism," he concluded, "is a source of causal chains which cannot be traced beyond a terminal point because they are lost in the unfathomable complexity of the organism." Like the physicist who works within the bounds of an unfathomable universe, Elsasser argues, the biologist must seek answers within a system that is no less unfathomable. (shrink)

[File is the introduction to the monograph] -/- Abstract to monograph -/- How and whether thinking affects perceiving is a deeply important question. Of course it is of scientific interest: to understand the human mind is to understand how we best distinguish its processes, how those processes interact, and what this implies for how and what we may know about the world. And so in the philosopher’s terms, this book is one on both mental architecture and the epistemology of perception. (...) But there is a more human interest. How we make contact with the world, and with one another, is of the most basic of importance. We can make both sensory contact and cognitive contact with the world. The first is traditionally supposed to be determined by the biological nature of our sensory systems, while the second is at least partly determined by us, what we have learned, our experiences, and so on. The most basic claim of the book is that this is mistaken and importantly so. Our sensory contact with the world can also change and in a way that is importantly affected by the cognitive contact that we have, or have had, with the world. Thinking does not just affect perceiving, thinking improves perceiving. If this is true, it changes not only how we should theorize the mind, it changes how we should understand, as individuals, our place in and contact with the world. (shrink)

In this paper an Artificial Neural Network (ANN) model, for predicting the category of a tumor was developed and tested. Taking patients’ tests, a number of information gained that influence the classification of the tumor. Such information as age, sex, histologic-type, degree-of-diffe, status of bone, bone-marrow, lung, pleura, peritoneum, liver, brain, skin, neck, supraclavicular, axillar, mediastinum, and abdominal. They were used as input variables for the ANN model. A model based on the Multilayer Perceptron Topology was established and trained using (...) data set which its title is “primary tumor” and was obtained from the University Medical Centre, Institute of Oncology, Ljubljana, Yugoslavia Test data evaluation shows that the ANN model is able to correctly predict the tumor category with 76.67 % accuracy. (shrink)

Twentieth century philosophers introduced the distinction between “objective rightness” and “subjective rightness” to achieve two primary goals. The first goal is to reduce the paradoxical tension between our judgments of (i) what is best for an agent to do in light of the actual circumstances in which she acts and (ii) what is wisest for her to do in light of her mistaken or uncertain beliefs about her circumstances. The second goal is to provide moral guidance to an agent who (...) may be uncertain about the circumstances in which she acts, and hence is unable to use her standard moral principle directly in deciding what to do. This paper distinguishes two important senses of “moral guidance”; proposes criteria of adequacy for accounts of subjective rightness; canvasses existing definitions for “subjective rightness”; finds them all deficient; and proposes a new and more successful account. It argues that each comprehensive moral theory must include multiple principles of subjective rightness to address the epistemic situations of the full range of moral decision-makers, and shows that accounts of subjective rightness formulated in terms of what it would reasonable for the agent to believe cannot provide that guidance. -/- . (shrink)

This paper considers an orectic penetration hypothesis which says that desires and desire-like states may influence perceptual experience in a non-externally mediated way. This hypothesis is clarified with a definition, which serves further to distinguish the interesting target phenomenon from trivial and non-genuine instances of desire-influenced perception. Orectic penetration is an interesting possible case of the cognitive penetrability of perceptual experience. The orectic penetration hypothesis is thus incompatible with the more common thesis that perception is cognitively impenetrable. It is of (...) importance to issues in the philosophy of mind and cognitive science, epistemology, and general philosophy of science. The plausibility of orectic perception can be motivated by some classic experimental studies, and some new experimental research inspired by those same studies. The general suggestion is that orectic penetration thus defined, and evidenced by the relevant studies, cannot be deflected by the standard strategies of the cognitive impenetrability theorist. (shrink)

We study the question of how to decompose Hilbert space into a preferred tensor-product factorization without any pre-existing structure other than a Hamiltonian operator, in particular the case of a bipartite decomposition into "system" and "environment." Such a decomposition can be defined by looking for subsystems that exhibit quasi-classical behavior. The correct decomposition is one in which pointer states of the system are relatively robust against environmental monitoring (their entanglement with the environment does not continually and dramatically increase) and remain (...) localized around approximately-classical trajectories. We present an in-principle algorithm for finding such a decomposition by minimizing a combination of entanglement growth and internal spreading of the system. Both of these properties are related to locality in different ways. This formalism could be relevant to the emergence of spacetime from quantum entanglement. (shrink)

Recent theorizing argues that online communication technologies provide powerful, although precarious, means of emotional regulation. We develop this understanding further. Drawing on subjective reports collected during periods of imposed social restrictions under COVID-19, we focus on how this precarity is a source of emo-tional dysregulation. We make our case by organizing responses into five distinct but intersecting dimensions wherein the precarity of this regulation is most relevant: infrastructure, functional use, mindful design (individual and social), and digital tact. Analyzing these reports, (...) along with examples of mediating technologies (i.e., self-view) and common interactive dynamics (e.g., gaze coordination), we tease out how breakdowns along these dimensions are sources of affective dysregulation. We argue that the adequacy of available technological resources and competencies of various kinds matter greatly to the types of emotional experiences one is likely to have online. Further research into online communication technologies as modula-tors of both our individual and collective well-being is urgently needed, especially as the echoes of the digital push that COVID-19 initiated are set to continue rever-berating into the future. (shrink)

The standard view of "believes" and other propositional attitude verbs is that such verbs express relations between agents and propositions. A sentence of the form “S believes that p” is true just in case S stands in the belief-relation to the proposition that p; this proposition is the referent of the complement clause "that p." On this view, we would expect the clausal complements of propositional attitude verbs to be freely intersubstitutable with their corresponding proposition descriptions—e.g., "the proposition that p"—as (...) they are in the case of "believes." In many cases, however, intersubstitution of that-clauses and proposition descriptions fails to preserve truth value or even grammaticality. These substitution failures lead some philosophers to reject the standard view of propositional attitude reports. Others conclude that propositional attitude verbs are systematically ambiguous. I reject both these views. On my view, the that-clause complements of propositional attitude verbs denote propositions, but proposition descriptions do not. (shrink)

There are good, even if inconclusive, reasons to think that cognitive penetration of perception occurs: that cognitive states like belief causally affect, in a relatively direct way, the contents of perceptual experience. The supposed importance of – indeed as it is suggested here, what is definitive of – this possible phenomenon is that it would result in important epistemic and scientific consequences. One interesting and intuitive consequence entirely unremarked in the extant literature concerns the perception of art. Intuition has it (...) that knowledge about art changes how one aesthetically evaluates artworks. A profound explanation of this intuitive fact is that perceptual experiences vary with artistic expertise. Cognitive penetration provides an explanatory mechanism for this latter effect. What one knows or otherwise thinks about art may affect, in one of two ways sketched below, how one perceives art. Differences in aesthetic evaluation may follow, either because high-level aesthetic properties can be perceptually represented or because they causally depend on low-level perceptible properties. All of this lends credence to the hypothesis that the expert better judges art because she better perceives art. And she better perceives art because she better knows art. (shrink)

Diabetes is a major public health issue that affects the nations of our time to a large extent and is described as a non-communicable epidemic. Diabetes mellitus is a common disease where there is too much sugar (glucose) floating around in your blood. This occurs because either the pancreas can’t produce enough insulin or the cells in body have become resistant to insulin. The concentration in this paper is on diagnosis diabetes by designing a proposed expert system. The main goal (...) of this expert system is to get the appropriate diagnosing of the illness, dealing with it quickly, and tips for permanent treatment whenever possible is given out. SL5 object expert system language was used for designing and implementing the proposed expert system. (shrink)

Expertise is a cognitive achievement that clearly involves experience and learning, and often requires explicit, time-consuming training specific to the relevant domain. It is also intuitive that this kind of achievement is, in a rich sense, genuinely perceptual. Many experts—be they radiologists, bird watchers, or fingerprint examiners—are better perceivers in the domain(s) of their expertise. The goal of this paper is to motivate three related claims, by substantial appeal to recent empirical research on perceptual expertise: Perceptual expertise is genuinely perceptual (...) and genuinely cognitive, and this phenomenon reveals how we can become epistemically better perceivers. These claims are defended against sceptical opponents that deny significant top-down or cognitive effects on perception, and opponents who maintain that any such effects on perception are epistemically pernicious. (shrink)

Racial epithets are terms used to characterize people on the basis of their race, and are often used to harm the people that they target. But what do racial epithets mean, and how do they work to harm in the way that they do? In this essay I set out to answer these questions by offering a pragmatic view of racial epithets, while contrasting my position with Christopher Hom's semantic view.

I propose and articulate a novel theory of desire, called the Revised Reward Theory. As the name suggests, the theory is based—and expands—on Arpaly and Schroeder’s (2014) Reward Theory of Desire. The initial Reward Theory identifies desires with states of the reward learning system such that for an organism to desire some P is for its reward system to treat P as a reward upon receipt. The Revised Reward Theory identifies desires with a different state of the same system, such (...) that for an organism to desire some P is for its reward system to expect or predict that P will be rewarding (roughly) prior to receipt. The difference amounts to equating desires with what we ultimately find rewarding or satisfying versus those that underlie our motivations to obtain that which we take ourselves to desire. I argue that the structure of the reward system is incompatible with the original Reward Theory but compatible with the Revised Reward Theory. I demonstrate that this difference has important philosophical implications. I focus on moral responsibility and demonstrate Arpaly and Schroeder’s argument, that addiction can mitigate moral responsibility, turns on this precise difference. Arpaly, Schroeder, and I all ascribe to a meta-theory called ‘natural kindism’ which identifies mental kinds with neurocognitive kinds. This discussion, in addition to defending a theory of desire, is intended to act as a proof of concept for natural kindism as offering a powerful framework for relating empirical results to philosophical issues. (shrink)

In this article, I apply Australian logician and ecofeminist philosopher Val Plumwood’s Feminism and the Mastery of Nature, specifically its alternative logic of “the dance of interaction,” to a controversial community-engagement program in my home state of Alabama. At Rural Studio, Auburn University students design free housing and public works for one of the poorest regions in the United States, known as the “Black Belt.” Through the lens of Plumwood’s ecofeminist dancing logic, the marginalized source of Rural Studio’s survival is (...) revealed to be the resilience of the disempowered majority-Black community. Inspired thereby, I sketch an ecofeminist choreography with three “dancing” concepts (namely Plumwood’s “the master model,” Vandana Shiva’s “nature’s logic,” and Ariel Salleh’s “holding”), acknowledging the resilience of the disempowered as a necessary step toward an ethically-sustainable aesthetics. (shrink)

In the United States, police use of force experts often maintain that controversial police shootings where an unarmed person’s hand gesture was interpreted as their “going for a gun” are justifiable. If an officer waits to confirm that a weapon is indeed being pulled from a jacket pocket or waistband, it may be too late to defend against a lethal attack. This article examines police policy norms for self-defense against “uncertain threats” in three contexts: (1) known in-progress violent crimes, (2) (...) interactions with civilians behaving non-aggressively, and (3) interactions with civilians behaving aggressively. It is argued that the context of a known in-progress violent crime gives rise to threat probability-, fairness-, and lesser evil-based reasons for a norm permitting police officers to use lethal force. However, in the contexts of civilians behaving non-aggressively and civilians behaving aggressively, such a norm is not justifiable. In the former case, I introduce two conditions, the Justification condition and the Valuing Civilian Lives condition, which I argue are not presently met. In the latter case, these two conditions again are not met; aggression may moreover be excused or justified due to background injustices around race and the criminal justice system. (shrink)

The problem of evil is an ideal topic for experimental philosophy. Suffering--which is at the heart of most prominent formulations of the problem of evil--is a universal human experience and has been the topic of careful reflection for millennia. However, interpretations of suffering and how it bears on the existence of God are tremendously diverse and nuanced. We might immediately find ourselves wondering why (and how!) something so universal might be understood in so many different ways. Why does suffering push (...) some people toward atheism while pushing others toward deeper faith? What cultural, psychological, or sociological differences account for this diversity of responses? And, importantly, what light might this diversity of responses shed on the problem of evil and how it has been formulated by philosophers in recent years? The primary aim of this paper is to highlight how the tools and resources of experimental philosophy might be fruitfully applied to the problem of evil. In the first section, we review some recent work in this area and describe the current state of this emergent body of literature. In the second section, we review the broader and more recent theoretical developments on the problem of evil. Finally, in the final section, we outline some potential areas of future empirical research that we see as especially promising given those developments. (shrink)

We often appeal to the notion of an agent’s commitment to action to characterize, e.g., an agent’s faithfulness to a promise she has given to another, her robust disposition to pursue a goal she values or cares about, and her determination to stick to that goal. In the philosophy of action, that notion is often associated with the idea of an agent’s intention to act. In ethics, it is associated primarily with the idea of an agent’s commitment to, or endorsement (...) of, a certain norm. This essay argues that both these ideas, of intention and of normative endorsement, are central to the –or, at least, an—ordinary notion of an agent’s (psychological) commitment to action. In so doing, the essay also sheds light on important features of intention. -/- Keywords: commitment – intention – normative endorsement – stability across contexts – coordination. (shrink)

Plato is associated with the idea that the body holds us back from knowing ultimate reality and so we should try to distance ourselves from its influence. This sentiment appears is several of his dialogues including Theaetetus where the flight from the physical world is compared to becoming like God. In some major dialogues of Plato's later career such as Philebus and Laws, however, the idea of becoming like God takes a different turn. God is an intelligent force that tries (...) to create order in the physical world. I argue that likeness to God in these dialogues involves imitating God's effort by trying to order our bodies, souls, and societies as intelligence directs. Becoming like Plato's God is not to abandon the world. It is to improve it. (shrink)

One sceptical rejoinder to those who claim that sensory perception is cognitively penetrable is to appeal to the involvement of attention. So, while a phenomenon might initially look like one where, say, a perceiver’s beliefs are influencing her visual experience, another interpretation is that because the perceiver believes and desires as she does, she consequently shifts her spatial attention so as to change what she senses visually. But, the sceptic will urge, this is an entirely familiar phenomenon, and it hardly (...) involves some special or theoretically important cognitive effect on sensory perception. Even supposing that the sceptic is correct about cases that are accurately described in this way, the rejoinder oversimplifies the possible roles that attention may play in mediating cognition and perception. This paper aims to identify these different roles, and by emphasis on empirical research on feature-based and object-based attention. What emerges is a plausible and well- evidenced mental schema that describes attention -mediated cognitive penetration. At the very least, the burden of proof is shifted to the sceptic, as he then must show that there are no mental phenomena involving attention in the more nuanced ways described here. One additional benefit of this analysis is that it illuminates various features of attention and its relation to both cognition and phenomenal consciousness. Therefore the analysis should be of interest to a broad range of theorists of the mind, and not just those invested in the cognitive penetration debate. (shrink)

Fictions evoke imagery, and their value consists partly in that achievement. This paper offers analysis of this neglected topic. Section 2 identifies relevant philosophical background. Section 3 offers a working definition of imagery. Section 4 identifies empirical work on visual imagery. Sections 5 and 6 criticize imagery essentialism, through the lens of genuine fictional narratives. This outcome, though, is not wholly critical. The expressed spirit of imagery essentialism is to encourage philosophers to ‘put the image back into the imagination’. The (...) weakened conclusion is that while an image is not essential to imagining, it should be returned to our theories of imagination. (shrink)

The introduction to a special issue of Religious Studies on the theme of experimental philosophy of religion.

Vision often dominates other perceptual modalities both at the level of experience and at the level of judgment. In the well-known McGurk effect, for example, one’s auditory experience is consistent with the visual stimuli but not the auditory stimuli, and naïve subjects’ judgments follow their experience. Structurally similar effects occur for other modalities (e.g. rubber hand illusions). Given the robustness of this visual dominance, one might not be surprised that visual imagery often dominates imagery in other modalities. One might be (...) surprised, however, that visual imagery often dominates perception in other modalities. This more controversial claim is motivated both by empirical data and by introspection. Some think of perception-perception visual dominance as epistemically good, holding that cases in which visual dominance misleads us (e.g. McGurk and rubber hand illusions) are cases in which the perceptual system resolves conflicts according to principles that are generally reliable. Here, we explore support for the more controversial claim that imagery-perception visual dominance is epistemically good. We suggest that, when the task is richly spatial, requiring for optimal performance the all-at-once identification of macro-spatial and allocentric properties (e.g. identifying the shape or location of a felt or heard object), the visual, whether perception or imagination, should dominate other modalities. Put another way, when identifying objects, one should go and look or, short of that, visually imagine candidate objects, and then follow the visual, even against conflicting perceptions from other modalities. For this broadly-typed category of of cognitive-perceptual task, vision does dominate and it should. (shrink)

It has been widely argued that words are analogous to species such that words, like species, are natural kinds. In this paper, I consider the metaphysics of word-kinds. After arguing against an essentialist approach, I argue that word-kinds are homeostatic property clusters, in line with the dominant approach to other biological and psychological kinds.

Both common sense and dominant traditions in art criticism and philosophical aesthetics have it that aesthetic features or properties are perceived. However, there is a cast of reasons to be sceptical of the thesis. This paper defends the thesis—that aesthetic properties are sometimes represented in perceptual experience—against one of those sceptical opponents. That opponent maintains that perception represents only low-level properties, and since all theorists agree that aesthetic properties are not low-level properties, perception does not represent aesthetic properties. I offer (...) a novel argument—what I call the argument from seeing-as—against that sceptic which moves from consideration of ambiguous figures to consideration of visual art. It concludes that aesthetic properties are sometimes perceived and delivers a general lesson for philosophy of perception. Contrary to extant theories of rich perceptual content, aesthetic properties are far better candidates for high-level perceptual contents than standardly theorized rich contents like natural kinds. (shrink)

Higher education institutions are mining and analyzing student data to effect educational, political, and managerial outcomes. Done under the banner of “learning analytics,” this work can—and often does—surface sensitive data and information about, inter alia, a student’s demographics, academic performance, offline and online movements, physical fitness, mental wellbeing, and social network. With these data, institutions and third parties are able to describe student life, predict future behaviors, and intervene to address academic or other barriers to student success (however defined). Learning (...) analytics, consequently, raise serious issues concerning student privacy, autonomy, and the appropriate flow of student data. We argue that issues around privacy lead to valid questions about the degree to which students should trust their institution to use learning analytics data and other artifacts (algorithms, predictive scores) with their interests in mind. We argue that higher education institutions are paradigms of information fiduciaries. As such, colleges and universities have a special responsibility to their students. In this article, we use the information fiduciary concept to analyze cases when learning analytics violate an institution’s responsibility to its students. (shrink)