Primary tubercular liver abscess in an immunocompetent adult: a case report

<p>Abstract</p> <p>Introduction</p> <p>Isolated primary tubercular abscess is one of the rare forms of extrapulmonary tuberculosis. A greater awareness of this rare clinical entity may help in commencing specific evidence-based therapy quickly and preventing undue morbidity and mortality.</p> <p>Case presentation</p> <p>A 30-year-old man, of Asian origin, developed a hepatic tubercular abscess which was not associated with any pulmonary or gastrointestinal tract foci of tuberculosis. An ultrasonogram of the abdomen showed an abscess in the right lobe of his liver which was initially diagnosed as an amoebic liver abscess. Subsequently, the pus from the lesion yielded <it>Mycobacterium tuberculosis </it>using the BACTEC TB 460 instrument and <it>Mycobacterium tuberculosis </it>deoxyribonucleic acid by polymerase chain reaction. The patient was started on systemic antitubercular therapy to which he responded favorably.</p> <p>Conclusion</p> <p>This report emphasizes the fact that, although a tuberculous liver abscess is a very rare entity, it should be included in the differential diagnosis of unknown hepatic mass lesions.</p

An estimated 400-800 million tons of prey are annually killed by the global spider community

Spiders have been suspected to be one of the most important groups of natural enemies of insects worldwide. To document the impact of the global spider community as insect predators, we present estimates of the biomass of annually killed insect prey. Our estimates assessed with two different methods suggest that the annual prey kill of the global spider community is in the range of 400-800 million metric tons (fresh weight), with insects and collembolans composing >90% of the captured prey. This equals approximately 1‰ of the global terrestrial net primary production. Spiders associated with forests and grasslands account for >95% of the annual prey kill of the global spider community, whereas spiders in other habitats are rather insignificant contributors over a full year. The spider communities associated with annual crops contribute less than 2% to the global annual prey kill. This, however, can be partly explained by the fact that annual crop fields are "disturbed habitats" with a low buildup of spider biomass and that agrobiont spiders often only kill prey over short time periods in a year. Our estimates are supported by the published results of exclusion experiments, showing that the number of herbivorous/detritivorous insects and collembolans increased significantly after spider removal from experimental plots. The presented estimates of the global annual prey kill and the relative contribution of spider predation in different biomes improve the general understanding of spider ecology and provide a first assessment of the global impact of this very important predator group

Towards Autonomous Artificial Agents? Proposal for a Naturalistic Activity-Based Model of (Artificial) Life

While the contemporary achievements of AI and robotics are indisputable, the issue of autonomy for artificial agents still looms ahead despite technological progress and rich conceptual debates. Drawing on recent theoretical propositions from the enactive approach to autonomy, we first highlight several limitations of what we call an identity-based model. Through the study of four real-life cases, we then not only argue that autonomy cannot be conflated with behavioral self-maintenance or organizational closure, but that it can sometimes violate these conditions. Finally, we propose a naturalistic activity-based model of autonomous agents that emphasizes the importance of norm-establishing processes distributed across an intricacy of milieus.info:eu-repo/semantics/publishe