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The ecological role of microorganisms is of utmost importance due to their multiple interactions with the environment. However, assessing the contribution of individual taxonomic groups has proven difficult despite the availability of high throughput data, hindering our understanding of such complex systems. Here, we propose a quantitative definition of guild that is readily applicable to metagenomic data. Our framework focuses on the functional character of protein sequences, as well as their diversifying nature. First, we discriminate functional sequences from the whole sequence space corresponding to a gene annotation to then quantify their contribution to the guild composition across environments. In addition, we identify and distinguish functional implementations, which are sequence spaces that have different ways of carrying out the function. In contrast, we found that orthology delineation did not consistently align with ecologically (or functionally) distinct implementations of the function. We demonstrate the value of our approach with two case studies: the ammonia oxidation and polyamine uptake guilds from the Malaspina circumnavigation cruise, revealing novel ecological dynamics of the latter in marine ecosystems. Thus, the quantification of guilds helps us to assess the functional role of different taxonomic groups with profound implications on the study of microbial communities., Competing Interests: The authors declare no competing interests., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

Piezoelectric power converters, where acoustic resonators replace the inductors as energy storage elements, promise much higher power density and higher efficiency compared to conventional circuits. Recently, lithium niobate (LiNbO3) piezoelectric resonators have been integrated within power converter circuits, showing good conversion efficiency, thanks to their high quality factor ( Q ) and electromechanical coupling ( k t 2 ). However, the converter output power range is limited by large spurious modes near resonance. This work reports a near-spurious-free LiNbO3 thickness shear (TS) resonator, demonstrating a high Q of 3500 and k t 2 of 45% at 5.94 MHz, with a fractional suppressed region of 35%. First, we identify the best LiNbO3 crystal orientation for efficient TS resonators. Then, we propose a novel acoustic design without busbars for spurious suppression, which is extensively simulated, fabricated, and characterized. Further analysis is done to identify existing spurious modes in our proposed design, specifically the effect of dicing on our TS resonator design. Upon optimization, LiNbO3 TS resonators could potentially empower a new design space for low-loss and compact power converters.

There are few studies on dementia and schizophrenia in older patients looking for structural differences. This paper aims to describe relation between cognitive performance and brain volumes in older schizophrenia patients. Twenty schizophrenic outpatients -10 without-dementia (SND), 10 with dementia (SD)- and fifteen healthy individuals -as the control group (CG)-, older than 50, were selected. Neuropsychological tests were used to examine cognitive domains. Brain volumes were calculated with magnetic resonance images. Cognitive performance was significantly better in CG than in schizophrenics. Cognitive performance was worst in SD than SND, except in semantic memory and visual attention. Hippocampal volumes showed significant differences between SD and CG, with predominance on the right side. Left thalamic volume was smaller in SD group than in SND. Structural differences were found in the hippocampus, amygdala, and thalamus; more evident in the amygdala and thalamus, which were mainly related to dementia. In conclusion, cognitive performance and structural changes allowed us to differentiate between schizophrenia patients and CG, with changes being more pronounced in SD than in SND. When comparing SND with SD, the functional alterations largely coincide, although sometimes in the opposite direction. Moreover, volume lost in the hippocampus, amygdala, and thalamus may be related to the possibility to develop dementia in schizophrenic patients.