| 161. |
|
|
| 162. |
- Lundblad, Lennart, et al.
(författare)
-
Thoracic gas volume measurements in paralyzed mice
- 2004
-
Ingår i: Annals of Biomedical Engineering. - 1573-9686. ; 32:10, s. 1420-1427
-
Tidskriftsartikel (refereegranskat)abstract
- We have previously measured thoracic gas volume (V-TG) in spontaneously breathing mice using a whole body plethysmograph and have now extended our technique to allow for V-TG measurements during paralysis. BALB/c mice were anesthetized and placed in a body-box and ventilated via a tracheostomy cannula through the box wall. Box pressure (P-b) and tracheal pressure (P-ao) were measured during spontaneous breathing, and again after paralysis while mechanically compressing the chest. V-TG was much larger after paralysis (0.49+/-0.06 ml, positive end-expiratory pressure=2 cmH(2)O) when compared with spontaneous breathing (0.31+/-0.01 ml). External chest compression produced looping in the plots of P-b versus P-ao that was attributable to gradual changes in P-b upon release of the mechanical chest compression and had the character of thermal transients. Under the assumption that the rate of heating of the air in the chamber was proportional to the pressure applied to the animal's chest, and that any increase in air temperature was dissipated by heat absorption by the chamber walls, we developed an algorithm that corrected for the thermal events. This yielded similar results for V-TG (0.30+/-0.02 ml) as obtained during spontaneous efforts. Our method may prove particularly useful when paralysis is required for the precise measurement of lung mechanics.
|
|
| 163. |
|
|
| 164. |
- Marlevi, David, doktorand, et al.
(författare)
-
Non-invasive estimation of relative pressure in turbulent flow using virtual work-energy
- 2020
-
Ingår i: Medical Image Analysis. - : Elsevier B.V.. - 1361-8415 .- 1361-8423. ; 60
-
Tidskriftsartikel (refereegranskat)abstract
- Vascular pressure differences are established risk markers for a number of cardiovascular diseases. Relative pressures are, however, often driven by turbulence-induced flow fluctuations, where conventional non-invasive methods may yield inaccurate results. Recently, we proposed a novel method for non-turbulent flows, νWERP, utilizing the concept of virtual work-energy to accurately probe relative pressure through complex branching vasculature. Here, we present an extension of this approach for turbulent flows: νWERP-t. We present a theoretical method derivation based on flow covariance, quantifying the impact of flow fluctuations on relative pressure. νWERP-t is tested on a set of in-vitro stenotic flow phantoms with data acquired by 4D flow MRI with six-directional flow encoding, as well as on a patient-specific in-silico model of an acute aortic dissection. Over all tests νWERP-t shows improved accuracy over alternative energy-based approaches, with excellent recovery of estimated relative pressures. In particular, the use of a guaranteed divergence-free virtual field improves accuracy in cases where turbulent flows skew the apparent divergence of the acquired field. With the original νWERP allowing for assessment of relative pressure into previously inaccessible vasculatures, the extended νWERP-t further enlarges the method's clinical scope, underlining its potential as a novel tool for assessing relative pressure in-vivo.
|
|
| 165. |
|
|
| 166. |
- Pascual, Unai, et al.
(författare)
-
Valuing nature's contributions to people : the IPBES approach
- 2017
-
Ingår i: Current Opinion in Environmental Sustainability. - : Elsevier BV. - 1877-3435. ; 26-27, s. 7-16
-
Forskningsöversikt (refereegranskat)abstract
- Nature is perceived and valued in starkly different and often conflicting ways. This paper presents the rationale for the inclusive valuation of nature's contributions to people (NCP) in decision making, as well as broad methodological steps for doing so. While developed within the context of the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), this approach is more widely applicable to initiatives at the knowledge–policy interface, which require a pluralistic approach to recognizing the diversity of values. We argue that transformative practices aiming at sustainable futures would benefit from embracing such diversity, which require recognizing and addressing power relationships across stakeholder groups that hold different values on human nature-relations and NCP.
|
|
| 167. |
- Pedro J, Aphalo, et al.
(författare)
-
Beyond the visible : a handbook of best practice in plant UV photobiology
- 2012. - 1
-
Ingår i: Handbook for research on the effects of ultraviolet radiation on plants. - : Helsingfors universitet. - 9789521083624 - 9789521083631 ; , s. 35-70
-
Bokkapitel (refereegranskat)abstract
- The writing of this handbook started 14 months ago and is the results of the work of six editors and sixteen authors. This version is a preprint prepared for the participants in the 2012 training school of the COST action 5 FA0906 ‘UV4growth’ at University of Málaga. We hope that you find the handbook useful, and that you will alert us of errors, and of difficult to understand sections or paragraphs. Please, send all such comments to mailto:pedro.aphalo@helsinki.fi?subject=TG1HandbookPre01feedback indicating page and line numbers. Many thanks for your help.
|
|
| 168. |
- Rahlff, Janina, et al.
(författare)
-
Lytic archaeal viruses infect abundant primary producers in Earth's crust
- 2021
-
Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 12:1
-
Tidskriftsartikel (refereegranskat)abstract
- The continental subsurface houses a major portion of life's abundance and diversity, yet little is known about viruses infecting microbes that reside there. Here, we use a combination of metagenomics and virus-targeted direct-geneFISH (virusFISH) to show that highly abundant carbon-fixing organisms of the uncultivated genus Candidatus Altiarchaeum are frequent targets of previously unrecognized viruses in the deep subsurface. Analysis of CRISPR spacer matches display resistances of Ca. Altiarchaea against eight predicted viral clades, which show genomic relatedness across continents but little similarity to previously identified viruses. Based on metagenomic information, we tag and image a putatively viral genome rich in protospacers using fluorescence microscopy. VirusFISH reveals a lytic lifestyle of the respective virus and challenges previous predictions that lysogeny prevails as the dominant viral lifestyle in the subsurface. CRISPR development over time and imaging of 18 samples from one subsurface ecosystem suggest a sophisticated interplay of viral diversification and adapting CRISPR-mediated resistances of Ca. Altiarchaeum. We conclude that infections of primary producers with lytic viruses followed by cell lysis potentially jump-start heterotrophic carbon cycling in these subsurface ecosystems. Little is known about viral-host interactions in the continental subsurface. Here, the authors use a combination of metagenomics, fluorescence in situ hybridization, and electron microscopy to show infections of abundant C-fixing subsurface archaea by lytic viruses.
|
|
| 169. |
- Rivas, M. J., et al.
(författare)
-
Population genomics of parallel evolution in gene expression and gene sequence during ecological adaptation
- 2018
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8:1
-
Tidskriftsartikel (refereegranskat)abstract
- Natural selection often produces parallel phenotypic changes in response to a similar adaptive challenge. However, the extent to which parallel gene expression differences and genomic divergence underlie parallel phenotypic traits and whether they are decoupled or not remains largely unexplored. We performed a population genomic study of parallel ecological adaptation among replicate ecotype pairs of the rough periwinkle (Littorina saxatilis) at a regional geographical scale (NW Spain). We show that genomic changes underlying parallel phenotypic divergence followed a complex pattern of both repeatable differences and of differences unique to specific ecotype pairs, in which parallel changes in expression or sequence are restricted to a limited set of genes. Yet, the majority of divergent genes were divergent either for gene expression or coding sequence, but not for both simultaneously. Overall, our findings suggest that divergent selection significantly contributed to the process of parallel molecular differentiation among ecotype pairs, and that changes in expression and gene sequence underlying phenotypic divergence could, at least to a certain extent, be considered decoupled processes. © 2018, The Author(s).
|
|
| 170. |
|
|
