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1.
Nat Commun ; 12(1): 3717, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162841

RESUMO

Rawls argued that fairness in human societies can be achieved if decisions about the distribution of societal rewards are made from behind a veil of ignorance, which obscures the personal gains that result. Whether ignorance promotes fairness in animal societies, that is, the distribution of resources to reduce inequality, is unknown. Here we show experimentally that cooperatively breeding banded mongooses, acting from behind a veil of ignorance over kinship, allocate postnatal care in a way that reduces inequality among offspring, in the manner predicted by a Rawlsian model of cooperation. In this society synchronized reproduction leaves adults in a group ignorant of the individual parentage of their communal young. We provisioned half of the mothers in each mongoose group during pregnancy, leaving the other half as matched controls, thus increasing inequality among mothers and increasing the amount of variation in offspring birth weight in communal litters. After birth, fed mothers provided extra care to the offspring of unfed mothers, not their own young, which levelled up initial size inequalities among the offspring and equalized their survival to adulthood. Our findings suggest that a classic idea of moral philosophy also applies to the evolution of cooperation in biological systems.


Assuntos
Comportamento Animal/fisiologia , Herpestidae/fisiologia , Reprodução/fisiologia , Comportamento Social , Animais , Animais Recém-Nascidos , Peso Corporal/fisiologia , Cruzamento , Feminino , Masculino , Modelos Teóricos , Gravidez , Predomínio Social
2.
Biol Lett ; 11(10)2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26510673

RESUMO

Dominant females in social species have been hypothesized to reduce the reproductive success of their subordinates by inducing elevated circulating glucocorticoid (GC) concentrations. However, this 'stress-related suppression' hypothesis has received little support in cooperatively breeding species, despite evident reproductive skews among females. We tested this hypothesis in the banded mongoose (Mungos mungo), a cooperative mammal in which multiple females conceive and carry to term in each communal breeding attempt. As predicted, lower ranked females had lower reproductive success, even among females that carried to term. While there were no rank-related differences in faecal glucocorticoid (fGC) concentrations prior to gestation or in the first trimester, lower ranked females had significantly higher fGC concentrations than higher ranked females in the second and third trimesters. Finally, females with higher fGC concentrations during the third trimester lost a greater proportion of their gestated young prior to their emergence from the burrow. Together, our results are consistent with a role for rank-related maternal stress in generating reproductive skew among females in this cooperative breeder. While studies of reproductive skew frequently consider the possibility that rank-related stress reduces the conception rates of subordinates, our findings highlight the possibility of detrimental effects on reproductive outcomes even after pregnancies have become established.


Assuntos
Glucocorticoides/análise , Herpestidae/fisiologia , Prenhez/metabolismo , Animais , Dominação-Subordinação , Fezes/química , Feminino , Gravidez , Estresse Fisiológico , Uganda
3.
Biol Lett ; 10(12): 20140898, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25540153

RESUMO

As breeding between relatives often results in inbreeding depression, inbreeding avoidance is widespread in the animal kingdom. However, inbreeding avoidance may entail fitness costs. For example, dispersal away from relatives may reduce survival. How these conflicting selection pressures are resolved is challenging to investigate, but theoretical models predict that inbreeding should occur frequently in some systems. Despite this, few studies have found evidence of regular incest in mammals, even in social species where relatives are spatio-temporally clustered and opportunities for inbreeding frequently arise. We used genetic parentage assignments together with relatedness data to quantify inbreeding rates in a wild population of banded mongooses, a cooperatively breeding carnivore. We show that females regularly conceive to close relatives, including fathers and brothers. We suggest that the costs of inbreeding avoidance may sometimes outweigh the benefits, even in cooperatively breeding species where strong within-group incest avoidance is considered to be the norm.


Assuntos
Mamíferos/fisiologia , Comportamento Sexual Animal , Animais , Feminino , Masculino , Dados de Sequência Molecular
4.
Oper Dent ; 36(1): 2-11, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21488724

RESUMO

OBJECTIVES: To (1) identify the methods that dentists in The Dental Practice-Based Research Network (DPBRN) use to diagnose dental caries; (2) quantify their frequency of use and (3) test the hypothesis that certain dentist and dental practice characteristics are significantly associated with their use. METHODS: A questionnaire about methods used for caries diagnosis was sent to DPBRN dentists who reported doing some restorative dentistry; 522 dentists participated. Questions included the use of dental radiographs, the dental explorer, laser fluorescence, air-drying and fiber-optic devices and magnification as used when diagnosing primary, secondary/recurrent or non-specific caries lesions. Variations on the frequency of their use were tested using multivariate analysis and Bonferroni tests. RESULTS: Overall, the dental explorer was the instrument most commonly used to detect primary occlusal caries and caries at the margins of existing restorations. In contrast, laser fluorescence was rarely used to help diagnose occlusal primary caries. For proximal caries, radiographs were used to help diagnose 75%­100% of lesions by 96% of the DPBRN dentists. Dentists who use radiographs most often to assess proximal surfaces of posterior teeth were significantly more likely to also report providing a higher percentage of patients with individualized caries prevention (p=.040) and seeing a higher percentage of pediatric patients (p=.001). CONCLUSION: The use of specific diagnostic methods varied substantially. The dental explorer and radiographs are still the most commonly used diagnostic methods..


Assuntos
Pesquisa Participativa Baseada na Comunidade , Cárie Dentária/diagnóstico , Pesquisa em Odontologia/organização & administração , Padrões de Prática Odontológica/estatística & dados numéricos , Testes de Atividade de Cárie Dentária/estatística & dados numéricos , Instrumentos Odontológicos/estatística & dados numéricos , Feminino , Fluorescência , Humanos , Lasers , Modelos Lineares , Masculino , Análise Multivariada , Radiografia Dentária/estatística & dados numéricos , Inquéritos e Questionários , Transiluminação/estatística & dados numéricos , Estados Unidos
5.
J Hosp Infect ; 45(4): 278-82, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10973744

RESUMO

The efficacy of Sterilox, a super-oxidized water holding a reduction/oxidation potential of greater than 950 mV was compared with the efficacy of glutaraldehyde against clinical isolates of Mycobacterium tuberculosis and Mycobacterium avium-intracellulare. An in use method using an automated bronchoscope washing machine demonstrated that over five cycles, Sterilox with a contact time of 5 min gave log10 reduction factors for M. tuberculosis and M. avium-intracellulare of >6 and >5, respectively. Glutaraldehyde with a contact time of 10 min gave log10 reduction factors for both M. tuberculosis and M. avium-intracellulare of >4, and at a contact time of 20 min >5 each. The non-toxic nature of Sterilox, together with the reduction in viable counts demonstrated in this study, suggest that the solution is an effective alternative mycobactericidal agent to the established disinfectants for the disinfection of bronchoscopes and, therefore, justifies further investigation.


Assuntos
Broncoscópios/microbiologia , Infecção Hospitalar/prevenção & controle , Desinfetantes/farmacologia , Contaminação de Equipamentos/prevenção & controle , Glutaral/farmacologia , Peróxido de Hidrogênio , Complexo Mycobacterium avium/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Oxidantes/farmacologia , Humanos , Escarro/microbiologia
6.
Gene ; 189(1): 139-41, 1997 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-9161425

RESUMO

We report the sequence of 3978 bp of the Agrobacterium tumefaciens chromosome which contains a putative operon encoding the homologues of the transmembrane proton channel protein MotA, and the flagellar switch proteins FliM, FliN and FliG. Two transposon insertions in fliG result in a non-flagellate phenotype, indicating that this gene at least is required for flagellar assembly.


Assuntos
Agrobacterium tumefaciens/genética , Proteínas de Bactérias/genética , Flagelos/genética , Genes Bacterianos , Família Multigênica , Óperon , Sequência de Aminoácidos , Proteínas de Bactérias/química , Clonagem Molecular , Flagelos/química , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
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