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. 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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)

If business requires ethical solutions that are viable in the liminal landscape between concepts and corporate office, then business ethics and corporate social responsibility should offer tools that can survive the trek, that flourish in this well-traveled, but often unarticulated, environment. Indeed, feminist ethics produces, accesses, and engages such tools. However, work in BE and CSR consistently conflates feminist ethics and feminine ethics and care ethics. I offer clarification and invoke the analytic power of three feminist ethicists 'in action' whose (...) investigations into the "grey zones" of harms; identity and representational conventions; and "asymmetrical reciprocity" harmonize with business ethics' requirements. (shrink)

Conscious experiences are characterized by mental qualities, such as those involved in seeing red, feeling pain, or smelling cinnamon. The standard framework for modeling mental qualities represents them via points in geometrical spaces, where distances between points inversely correspond to degrees of phenomenal similarity. This paper argues that the standard framework is structurally inadequate and develops a new framework that is more powerful and flexible. The core problem for the standard framework is that it cannot capture precision structure: for example, (...) consider the phenomenal contrast between seeing an object as crimson in foveal vision versus merely as red in peripheral vision. The solution I favor is to model mental qualities using regions, rather than points. I explain how this seemingly simple formal innovation not only provides a natural way of modeling precision, but also yields a variety of further theoretical fruits: it enables us to formulate novel hypotheses about the space and structures of mental qualities, formally differentiate two dimensions of phenomenal similarity, generate a quantitative model of the phenomenal sorites, and define a measure of discriminatory grain. A noteworthy consequence is that the structure of the mental qualities of conscious experiences is fundamentally different from the structure of the perceptible qualities of external objects. (shrink)

The proliferation of Internet of Things (IoT) devices has introduced a range of opportunities for enhanced connectivity, automation, and efficiency. However, the vast array of interconnected devices has also raised concerns regarding cybersecurity, particularly due to the limited resources and diverse nature of IoT devices. Intrusion detection systems (IDS) have emerged as critical tools for identifying and mitigating security threats. This paper proposes a Multi-Layer Intrusion Detection Framework for IoT systems, leveraging Ensemble Machine Learning (EML) techniques to improve the accuracy (...) and effectiveness of detecting intrusions. The proposed framework integrates multiple layers of defense, including data preprocessing, feature extraction, classification, and post-processing, to provide a robust solution to IoT security challenges. This research explores the application of EML methods such as Random Forests, AdaBoost, and Gradient Boosting, combining them into a unified model to detect and mitigate various types of attacks in IoT environments. Experimental results demonstrate the superiority of the proposed framework in terms of detection accuracy, false positive rate, and computational efficiency. (shrink)

This paper examines the idea of "objective phenomenology," or a way of understanding the phenomenal character of conscious experiences that doesn’t require one to have had the kinds of experiences under consideration. My central thesis is that structural facts about experience—facts that characterize purely how conscious experiences are structured—are objective phenomenal facts. I begin by precisifying the idea of objective phenomenology and diagnosing what makes any given phenomenal fact subjective. Then I defend the view that structural facts about experience are (...) objective. I also argue that structural facts about experience, despite being objective, nevertheless still give rise to an explanatory gap. (shrink)

The mathematical developments of the 19th century seemed to undermine Kant’s philosophy. Non-Euclidean geometries challenged Kant’s view that there is a spatial intuition rich enough to yield the truth of Euclidean geometry. Similarly, advancements in algebra challenged the view that temporal intuition provides a foundation for both it and arithmetic. Mathematics seemed increasingly detached from experience as well as its form; moreover, with advances in symbolic logic, mathematical inference also seemed independent of intuition. This paper considers various philosophical responses to (...) these changes, focusing on the idea of modifying Kant’s conception of intuition in order to accommodate the increasing abstractness of mathematics. It is argued that far from clinging to an outdated paradigm, programs based on new conceptions of intuition should be seen as motivated by important philosophical desiderata, such as the truth, apriority, distinctiveness and autonomy of mathematics. (shrink)

In the science of consciousness, it’s oftentimes assumed that some creatures (or mental states) are more conscious than others. But in recent years, a number of philosophers have argued that the notion of degrees of consciousness is conceptually confused. This paper (1) argues that the most prominent objections to degrees of consciousness are unsustainable, (2) examines the semantics of ‘more conscious than’ expressions, (3) develops an analysis of what it is for a degreed property to count as degrees of consciousness, (...) and (4) applies the analysis to various theories of consciousness. I argue that whether consciousness comes in degrees ultimately depends on which theory of consciousness turns out to be correct. But I also argue that most theories of consciousness entail that consciousness comes in degrees. (shrink)

This paper develops a theory of analog representation. We first argue that the mark of the analog is to be found in the nature of a representational system’s interpretation function, rather than in its vehicles or contents alone. We then develop the rulebound structure theory of analog representation, according to which analog systems are those that use interpretive rules to map syntactic structural features onto semantic structural features. The theory involves three degree-theoretic measures that capture three independent ways in which (...) a system can be more or less analog. We explain how our theory improves upon prior accounts of analog representation, provides plausible diagnoses for novel challenge cases, extends to hybrid systems that are partially analog and partially symbolic, and accounts for some of the advantages and disadvantages of representing analogically versus symbolically. (shrink)

Individualistic traditions of autonomy have long been critiqued by feminists for their atomistic and asocial presentation of human agents. Relational approaches to autonomy were developed as an alternative to these views. Relational accounts generally capture a more socially informed picture of human agents, and aim to differentiate between social phenomena that are conducive to our agency versus those that pose a hindrance to our agency. In this article, I explore the various relational conceptualizations of autonomy profferred to date. I critically (...) review some of the ongoing internal disputes within the relational autonomy literature, and conclude the article by taking stock of the value of relational autonomy despite these unresolved debates. (shrink)

This paper examines visual representation from a distinctive, interdisciplinary perspective that draws on ethics, visual studies and critical race theory. Suggests ways to clarify complex issues of representational ethics in marketing communications and marketing representations, suggesting an analysis that makes identity creation central to societal marketing concerns. Analyzes representations of the exotic Other in disparate marketing campaigns, drawing upon tourist promotions, advertisements, and mundane objects in material culture. Moreover, music is an important force in marketing communication: visual representations in music (...) promotions are also explored as data for inquiry. Offers an alternative to phenomenologically based approaches in marketing and consumer research scholarship that use consumer responses to generate data. Contributes additional insight into societal marketing and places global marketing processes within the intersection of ethics, aesthetics and representation. (shrink)

Our reluctance to demystify grief is a sign of the distinctive obligation and discomfort that people feel towards those who have died. These feelings, however, are instructive about the nature of grief. As a vehicle of a living person’s relation to the dead, grief is mysterious—and we are rightly reluctant to take that mystery away. But grief is not to be avoided by philosophy on that account. I defend a less Romantic view of grief, in which a grieving person’s experience (...) of “normal” grief: 1) is felt to require an objectively recognized loss; 2) is felt to be dedicated to that lost object; 3) seems to most people to be something that she ought to feel; and 4) probably ought not to be medicalized, nor consequently medicated. This view of grief affords an understanding and appreciation of this rather special and important emotion without reducing its mystery. (shrink)

Families play an essential role in deceased organ procurement. As the person cannot directly communicate his or her wishes regarding donation, the family is often the only source of information regarding consent or refusal. We provide a systematic description and analysis of the different roles the family can play, and actions the family can take, in the organ procurement process across different jurisdictions and consent systems. First, families can inform or update healthcare professionals about a person’s donation wishes. Second, families (...) can authorize organ procurement in the absence of deceased’s preferences and the default is not to remove organs, and oppose donation where there is no evidence of preference but the default is to presume consent; in both cases, the decision could be based on their own wishes or what they think the deceased would have wanted. Finally, families can overrule the known wishes of the deceased, which can mean preventing donation, or permitting donation when the deceased refused it. We propose a schema of 4 levels on which to map these possible family roles: no role, witness, surrogate, and full decisional authority. We conclude by mapping different jurisdictions onto this schema to provide a more comprehensive understanding of the consent system for organ donation and some important nuances about the role of families. This classificatory model aims to account for the majority of the world’s consent systems. It provides conceptual and methodological guidance that can be useful to researchers, professionals, and policymakers involved in organ procurement. (shrink)

Nguyen argues that only his radically pragmatic account and Sterken’s indexical account can capture what we call the positive data. We present some new data, which we call the negative data, and argue that no theory of generics on the market is compatible with both the positive data and the negative data. We develop a novel version of the indexical account and show that it captures both the positive data and the negative data. In particular, we argue that there is (...) a semantic constraint that, in any context, the semantic value of GEN is upward monotone and non-symmetric. On the other hand, the pragmatic account has difficulty accommodating the negative data. This is because no pragmatic principles have been developed that can explain the negative data. In the paper, we focus on only the pragmatic account and the indexical account, but our discussion has broad implications for the debate on generics: any empirically adequate accounts of generics must be flexible enough to accommodate the positive data and yet constrained enough to accommodate the negative data. (shrink)

To address the rising concern that algorithmic decision-making may reinforce discriminatory biases, researchers have proposed many notions of fairness and corresponding mathematical formalizations. Each of these notions is often presented as a one-size-fits-all, absolute condition; however, in reality, the practical and ethical trade-offs are unavoidable and more complex. We introduce a new approach that considers fairness—not as a binary, absolute mathematical condition—but rather, as a relational notion in comparison to alternative decisionmaking processes. Using US mortgage lending as an example use (...) case, we discuss the ethical foundations of each definition of fairness and demonstrate that our proposed methodology more closely captures the ethical trade-offs of the decision-maker, as well as forcing a more explicit representation of which values and objectives are prioritised. (shrink)

“A Phenomenology of Seeing and Affect in a Polarized Climate,” focuses on the polarized political climate that reflects racial and class differences in the wake of the Trump election. She explores how to see differently about those with whom one disagrees—that is in this specific scenario for Lee, the Trump supporters, including Asian American members of her own family. Understanding Maurice Merleau-Ponty’s exploration of the interstice between the visible and the invisible, if human beings are to see otherwise, we need (...) to disrupt the ready association between the visible and the invisible. Here, she explores the function of affect for the possibility of this break. The phenomenological understanding of emotion does not necessarily empower emotion with any sort of superlative force, especially over reason. But a subject’s emotion chiasmatically reflects the world and vice versa. The caustic and strong emotions felt by people about this presidency reflects the entrenched political climate in our society and chiasmatically the entrenched political climate embroils people in strong emotions that make it difficult to see those with whom we disagree as people we can trust and consider reasonable. To break out of this standoff, to see differently about Trump supporters, one needs to feel differently about them as well. (shrink)

Some philosophers think that life is worth living not merely because of the goods and the bads within it, but also because life itself is good. I explain how this idea can be formalized by associating each version of such of a view with a function from length of life to the value generated by life itself. Then I argue that every version of the view that life itself is good faces some version of the following dilemma: either (1) good (...) human lives are worse than very long lives wholly devoid of pleasure, desire-satisfaction, knowledge, or any other goods, or (2) very short lives containing nothing but suffering are worth living. Since neither result is plausible, we ought to reject the view that life itself is good. On the view I favor, any given life may be worth living because of the goods that it contains, but life itself is neutral. (shrink)

The syntactic structure of the deontic “ought” has been much debated in philosophy and linguistics. Schroeder argues that the deontic “ought” is syntactically ambiguous in the sense that it can be associated with either a control or raising construction. He distinguishes between deliberative and evaluative “ought”s and argues that the deliberative “ought” is control while the evaluative “ought” is raising. However, if there is a control sense of “ought,” it implies that there is a sense of “ought” in which the (...) word carries an external argument. Chrisman (2012) proposes two linguistic tests to verify this prediction. I add a new test, which I call the intensionality test, to the list. (shrink)

Exploring the intimate tie between body movement and space and time, Lee begins with the position that body movement generates space and time and explores the ethical implications of this responsibility for the situations one’s body movements generate. Whiteness theory has come to recognize the ethical responsibility for situations not of one’s own making and hence accountability for the results of more than one’s immediate personal conscious decisions. Because of our specific history, whites have developed a particular embodiment and body (...) movement that generates places that can only be characterized as more comfortable and more enabling to whites. (shrink)

The standard versions of predicativism are committed to the following two theses: proper names are count nouns in all their occurrences, and names do not refer to objects but express name-bearing properties. The main motivation for predicativism is to provide a uniform explanation of referential names and predicative names. According to predicativism, predicative names are fundamental and referential names are explained by appealing to a null determiner functioning like “the” or “that.” This paper has two goals. The first is to (...) reject the predicativists’ explanation of the two types of names. I present three syntactic counterexamples to the predicativists’ account of referential names: incorporation, modification, and measure phrase uses. The second goal is to present a novel strategy to explain the two types of names. I propose that referential names are fundamental but that there are null morphemes available for transforming a name into a count noun (and possibly into other syntactic categories). (shrink)

This paper reconstructs the function argument of Aristotle’s Eudemian Ethics 2.1. The argument seeks to define happiness through the method of division; shows that the highest good is better than all four of the goods of the soul, not only two, as commentators have thought; and unlike the Nicomachean argument, makes the highest good definitionally independent of the human function.

The standard semantics for counterfactuals ensures that any counterfactual with a true antecedent and true consequent is itself true. There have been many recent attempts to amend the standard semantics to avoid this result. I show that these proposals invalidate a number of further principles of the standard logic of counterfactuals. The case against the automatic truth of counterfactuals with true components does not extend to these further principles, however, so it is not clear that rejecting the latter should be (...) a consequence of rejecting the former. Instead I consider how one might defuse putative counterexamples to the truth of true-true counterfactuals. (shrink)

When are logical theories equivalent? I discuss the notion of ground-equivalence between logical theories, which can be useful for various theoretical reasons, e.g., we expect ground-equivalent theories to have the same ontological bearing. I consider whether intertranslatability is an adequate criterion for ground-equivalence. Jason Turner recently offered an argument that first-order logic and predicate functor logic are ground-equivalent in virtue of their intertranslatability. I examine his argument and show that this can be generalized to other intertranslatable logical theories, which supports (...) the following: intertranslatability implies ground-equivalence. I also argue, however, that this ground-equivalence argument can be challenged as it faces a dilemma. The dilemma arises because the argument allows two distinct readings, the ‘internal’ and the ‘external’ reading. I argue that the argument turns out to be unsuccessful in both readings. The upshot of this dilemma in both philosophy of logic and metaphysics is considered. (shrink)

A response to a declaration in 'Le Monde', 'Luttons efficacement contre les théories du complot' by Gérald Bronner, Véronique Campion-Vincent, Sylvain Delouvée, Sebastian Dieguez, Karen Douglas, Nicolas Gauvrit, Anthony Lantian, and Pascal Wagner-Egger, published on June the 6th, 2016.

I present and discuss a counterexample to Kendall Walton's necessary condition for fictionality that arises from considering serial fictions. I argue that although Walton has not in fact provided a necessary condition for fictionality, a more complex version of Walton's condition is immune from the counterexample.

Many philosophers accept both of the following claims: (1) consciousness matters morally, and (2) species membership doesn’t matter morally. In other words, many reject speciesism but accept what we might call 'sentientism'. But do the reasons against speciesism yield analogous reasons against sentientism, just as the reasons against racism and sexism are thought to yield analogous reasons against speciesism? This paper argues that speciesism is disanalogous to sentientism (as well as racism and sexism). I make a case for the following (...) asymmetry: (a) some non-humans clearly have interests, but (b) no non-conscious entities clearly have interests. This asymmetry, I argue, renders sentientism resistant to the standard argument against speciesism. (shrink)

Are a material object, such as a statue, and its constituting matter, the clay, parts of one another? One wouldn't have thought so, and yet a number of philosophers have argued that they are. I review the arguments for this surprising claim showing how they all fail. I then consider two arguments against the view concluding that there are both pre-theoretical and theoretical considerations for denying that the statue and the clay are mutual parts.

Understanding science requires appreciating the values it presupposes and its social context. Both the values that scientists hold and their social context can affect scientific communication. Philosophers of science have recently begun studying scientific communication, especially as it relates to public policy. Some have proposed “guiding principles for communicating scientific findings” to promote trust and objectivity. This paper contributes to this line of research in a novel way using behavioural experimentation. We report results from three experiments testing judgments about the (...) trustworthiness, competence and objectivity of scientists. More specifically, we tested whether such judgments are affected by three factors: consulting or not consulting nonscientists, conducting research under a restrictive or non-restrictive governmental communication policy, and the source of a lab’s funding (i.e., government funding, private funding, or a combination of the two). We found that each of these factors affects ordinary judgments of trustworthiness, competence and objectivity. These findings support several recommendations that could help improve scientific communication and communication policies. (shrink)

Epistemic injustices are wrongs that agents can suffer in their capacity as knowers. In this article, I offer a conceptualisation of a phenomenon I call anticipatory epistemic injustice, which I claim is a distinct and particularly pernicious type of epistemic injustice worthy of independent analysis. I take anticipatory epistemic injustice to consist in the wrongs that agents can suffer as a result of anticipated challenges in their process of taking up testimony-sharing opportunities. I distinguish my account from paradigmatic cases of (...) epistemic injustice, such as Miranda Fricker’s concepts of testimonial injustice and hermeneutical injustice; additionally, I differentiate my view from Kristie Dotson’s account of testimonial smothering. I argue, ultimately, that anticipatory epistemic injustice is a useful addition to our current taxonomy of epistemic injustices, as it has promising explanatory potential for a range of non-standard cases of epistemic injustice. (shrink)

The question of authenticity centers in the lives of women of color to invite and restrict their representative roles. For this reason, Gayatri Chakravorty Spivak and Uma Narayan advocate responding with strategic essentialism. This paper argues against such a strategy and proposes an epistemic understanding of the question of authentic- ity. The question stems from a kernel of truth—the connection between experience and knowledge. But a coherence theory of knowledge better captures the sociality and the holism of experience and knowledge.

Natalie Stoljar posits that those who have internalized oppressive norms lack normative competence, which requires true beliefs and critical reflection. A lack of normative competence makes agents nonautonomous, according to Stoljar. This framework is thereby meant to address what she calls the “feminist intuition”—the intuition that oppressive norms are incompatible with autonomy. On my view, however, Stoljar’s normative competence account of autonomy is subject to a worrying problem. Her account misattributes nonautonomy to those who perpetrate the oppression, making those who (...) are oppressed and those who oppress count as equally nonautonomous. I argue that this is implausible and demonstrate in this paper that we can establish an asymmetry of autonomy between those who oppress others and those who are made the target of oppression. (shrink)

I assess a number of connected ideas about temporal experience that are introspectively plausible, but which I believe can be argued to be incorrect. These include the idea that temporal experiences are extended experiential processes, that they have an internal structure that in some way mirrors the structure of the apparent events they present, and the idea that time in experience is in some way represented by time itself. I explain how these ideas can be developed into more sharply defined (...) views, and then argue that these views are inconsistent with certain empirical facts about how time is represented in the brain. These facts instead support a kind of atomic view, on which temporal experiences are temporally unstructured atoms. (shrink)

Kevin Elliott’s A Tapestry of Values is a terrific book, chock full of valuable case studies and incisive analyses. It aims to be useful not only to students of philosophy of science and the other areas of science studies but also to practicing scientists, policymakers, and the public at large—a tall order. And it succeeds admirably for many of these folks. In my comments I suggest what it would need for the rest.

For Hannah Arendt, the federal system is an effective mode of organizing different sources of power while avoiding sovereign politics. This article aims to contribute two specific claims to the burgeoning scholarship on Arendt's international federalism. First, Arendt's international thoughts call for balancing two demands: the domestic need for human greatness and flourishing and the international demand for regulation and cooperation. Second, her reflections on council-based federalism offer a nuanced position that views the dual elements of equality in politics (intra-state (...) and interstate equality) as neither contradictory nor reconciliatory but rather as ideal types along a continuum. This study shows that, through the unique form of federalism emphasizing the need to balance two demands of free politics with a clear acknowledgement of its precariousness, Arendt's thinking adds much-needed sensitivity to international discourse. (shrink)

A number of philosophers have recently proposed several alleged cases of “knowledge from falsehood,” i.e., cases of inferential knowledge epistemised by an inference with a false crucial premise. This paper examines such cases and argues against interpreting them as cases of knowledge from falsehood. Specifically, I argue that the inferences in play in such cases are in no position to epistemise their conclusions.

This paper explores the liar paradox and its implications for logic and philosophical reasoning. It analyzes the paradox using classical logic principles and paraphrases it as "affirmation of the falsity of the very affirmation." The study draws connections between the liar paradox and Hegel's speculative sentence and suggests it functions as a "quasi-speculative sentence." Additionally, it examines parallels with the logocentric predicament and the determinist's assertion, highlighting their paradoxical nature. Through these analyses, the paper aims to illuminate the fundamental paradoxes (...) in our reasoning and logic. (shrink)

I sketch here an intuitive picture of repeatable artworks as created types, which are individuated in part by historical paths (re)production. Although attractive, this view has been rejected by a number of authors on the basis of general claims about abstract objects. On consideration, however, these general claims are overgeneralizations, which whilst true of some abstracta, are not true of all abstract objects, and in particular, are not true of created types. The intuitive picture of repeatable artworks as created types (...) is, then, left in place. (shrink)

The increasing application of artificial intelligence (AI) to healthcare raises both hope and ethical concerns. Some advanced machine learning methods provide accurate clinical predictions at the expense of a significant lack of explainability. Alex John London has defended that accuracy is a more important value than explainability in AI medicine. In this article, we locate the trade-off between accurate performance and explainable algorithms in the context of distributive justice. We acknowledge that accuracy is cardinal from outcome-oriented justice because it helps (...) to maximize patients’ benefits and optimizes limited resources. However, we claim that the opaqueness of the algorithmic black box and its absence of explainability threatens core commitments of procedural fairness such as accountability, avoidance of bias, and transparency. To illustrate this, we discuss liver transplantation as a case of critical medical resources in which the lack of explainability in AI-based allocation algorithms is procedurally unfair. Finally, we provide a number of ethical recommendations for when considering the use of unexplainable algorithms in the distribution of health-related resources. (shrink)

This paper gives significance to the concept of continuity in addressing the contemporary mind-body problem. Building upon philosophical definitions and insights from empirical brain science, the paper argues for "ontology of continuity" as a way to bridge between the mental and physical. To overcome the challenge of Kim’s causal overdetermination, the paper introduces a dual-neural process model, where subjective experiences and neural activities co-depend and influence each other in a quasi-parallel manner. This model seeks to reconcile idealism and physicalism, proposing (...) that continuity serves as a fundamental ontological construct connecting the mental and physical realms. (shrink)

Derrida suggests in Speech a n d Phenomena that for Husserl subjectivity is constituted and entails no identity with itself at the level of the living present. He further suggests that Husserl’s understanding of absolute subjectivity is “as absolutely present and absolutely self-present being, only in its opposition to the object.”’ In making such claims, Derrida is not giving as much weight to Husserl’s manuscripts from the 1930s as those warrant. The manuscripts may serve to draw Derrida’s claims into question.2 (...) They provide a n interesting look at the question of subjectivity in light of intersubjectivity and present the possibility of conceiving identity and alterity within the streaming living present. The ambiguity and complexity we find in Husserl’s manuscripts in particular suggests that Husserl was prepared t o address absence even at the most fundamental level of phenomenological discovery. In the following, I will explore several of Husserl’s manuscripts in order to indicate how he might escape Derrida’s ~ r i t i q u e . ~ This will raise several questions with respect to the phenomenological subject and its relation to the alterity of the other. Through such an investi- gation, we will see how it is possible to accept Derrida’s criticism of a metaphysics of presence, while recognizing that the criticism does not mean we must reject Husserlian phenom- enology as an example of such. (shrink)

The context of international health research involving human subjects, and this should appear obvious, is the human community. As such, basic questions of how human beings should be treated by other human beings, particularly in situations of unequal power – e.g., in the form of control, choice, or opportunity – lay at the foundations of related ethical discourse when ethics are discussed at all. I trace a narrative that follows upon a recent revision process of international guidelines for biomedical research (...) involving human subjects. I focus in particular upon the issue of a standard of care. In the second section, I draw upon philosophers John Rawls, Claudia Card, and Allen Buchanan to discuss concerns regarding the 'least advantaged members of society' in the context of global inequality. The paper includes reflections upon pedagogy in courses focused upon international health research involving human subjects. (shrink)

Is A & C sufficient for the truth of ‘if A were the case, C would be the case’? Jonathan Bennett thinks not, although the counterexample he gives is inconsistent with his own account of counterfactuals. In any case, I argue that anyone who accepts the case of Morgenbesser's coin, as Bennett does, should reject Bennett’s counterexample. Moreover, I show that the principle underlying his counterexample is unmotivated and indeed false. More generally, I argue that Morgenbesser’s coin commits us to (...) the sufficiency of A & C for the truth of the corresponding counterfactual. (shrink)

Are counterfactuals with true antecedents and consequents automatically true? That is, is Conjunction Conditionalization: if (X & Y), then (X > Y) valid? Stalnaker and Lewis think so, but many others disagree. We note here that the extant arguments for Conjunction Conditionalization are unpersuasive, before presenting a family of more compelling arguments. These arguments rely on some standard theorems of the logic of counterfactuals as well as a plausible and popular semantic claim about certain semifactuals. Denying Conjunction Conditionalization, then, requires (...) rejecting other aspects of the standard logic of counterfactuals, or else our intuitive picture of semifactuals. (shrink)

I give an account of the difference between "Holistic" and "Atomistic" views of conscious experience. On the Holistic view, we enjoy a unified "field" of awareness, whose parts are mere modifications of the whole, and therefore owe their existence to the whole. There is some tendency to saddle those who reject the Holistic field model with a (perhaps) implausible "building block" view. I distinguish a number of different theses about the parts of an experience that are suggested by the "building (...) block" metaphor, but which can be rejected by those who also reject the holistic field view. (shrink)

In the standard theory of deontic modals, ‘ought’ is understood as expressing a propositional operator. However, this view has been called into question by Almotahari and Rabern’s puzzle about deontic ‘ought’, according to which the ethical principle that one ought to be wronged by another person rather than wrong them is intuitively coherent but the standard theory makes it incoherent. In this paper, I take up Almotahari and Rabern’s challenge and offer a refinement of the standard theory to handle the (...) puzzle. I propose that ‘ought’ is evaluated relative to contextual parameters (e.g., Kratzer’s conversational backgrounds, Finlay and Snedegar’s alternative sets) and those contextual parameters are sensitive to agents as well as possible worlds. (shrink)

When Mill published The Subjection of Women in 1869 he wanted to replace the domination of one sex by the other laws based on ‘a principle of perfect equality’. It is widely complained, however, that even advanced countries have still failed to achieve equality between the sexes. Power and wealth and influence are still overwhelmingly in the hands of men. But equalities of these kinds are not the ones required by the principle of equality that Mill had in mind; and, (...) furthermore, a principle that demanded them would actually be incompatible with Mill’s. The conclusion is not, however, that social policies dealing with men and women are all they should be. It is just that although the fundamental problems of feminism could be – and to a considerable extent still can be – expressed in terms of requirements for justice and equality, we have now reached a stage where concentrating on these ideas can distort the real problems, and may actually impede the kind of progress that is needed. (shrink)

Internet of Things (IoT) devices have transformed various industries, enabling advanced functionalities across domains such as healthcare, smart cities, and industrial automation. However, the increasing number of connected devices has raised significant concerns regarding their security. IoT networks are highly vulnerable to a wide range of cyber threats, making Intrusion Detection Systems (IDS) critical for identifying and mitigating malicious activities. This paper proposes a hybrid approach for intrusion detection in IoT networks by combining Machine Learning (ML) techniques with Signature-Based Methods. (...) The hybrid model leverages the strengths of both methodologies to achieve high detection accuracy, reduced false positives, and the ability to identify both known and unknown threats. We explore the integration of ML classifiers such as Random Forest, Support Vector Machines, and k-Nearest Neighbors with traditional signature-based techniques to create a robust IDS solution. The effectiveness of the proposed approach is evaluated using a publicly available IoT dataset, demonstrating its capability to detect a wide variety of attacks with high precision and recall. (shrink)

Researchers have recognized that interpersonal trust consists of different dimensions. These dimensions suggest that trust can be rational, cognitive, or affective. Affect, which includes moods and emotions, is likely to have a direct impact on the affective dimension. On the other hand, there are also studies showing that affect indirectly influence cognitive judgments. Nonetheless, in this chapter we argue that the impact of affect on judgment will not be the same on all individuals. In effect, the impact varies, depending on (...) the individual's attention to affect, motivation to use or guard against affect, or regulation of affect. All this may suggest that an individual's abilities or tendencies to manage affect will have implication on his or her trust relationships with others. (shrink)

Some have claimed that moral bioenhancement undermines freedom and authenticity – thereby making moral bioenhancement problematic or undesirable – whereas others have said that moral bioenhancement does not undermine freedom and authenticity – thereby salvaging its ethical permissibility. These debates are characterized by a couple of features. First, a positive relationship is assumed to hold between these agency-related concepts and the ethical permissibility of moral bioenhancement. Second, these debates are centered around individualistic conceptions of agency, like free choice and authenticity, (...) which hail from an atomistic tradition of autonomy. My view is that emphasizing individualistic conceptions of autonomy do not provide particularly strong foundations on which to argue about the issue of the permissibility of moral bioenhancement. This is because individualistic autonomy is not the kind of agency-related consideration we ought to value. Instead, I propose that we investigate the relationship between moral bioenhancement and a more relational kind of autonomy. Focusing on this latter relationship, on my view, clarifies the potential for moral bioenhancement to support or enhance people’s autonomy. (shrink)

This article draws in particular on existential-phenomenological notions of “witnessing.” Witnessing, often conceived in the context of testimony, obviously involves epistemological concerns, such as how we come to know through the experiences and reports of others. I shall argue, however, that witnessing as a mode of intersubjectivity offers understandings that involve questions about how people come to be. More specifically, I want to consider the positive potential of “witnessing” to disrupt intersubjective completeness or closure, particularly as this relates to work (...) on organizing subjectivities, as well as, in the field of organization studies. (shrink)