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71.
Mariska Wesseling Lode Bosmans Christophe Van Dijck Jos Vander Sloten Roel Wirix-Speetjens Ilse Jonkers 《Computer methods in biomechanics and biomedical engineering》2019,22(4):376-385
To account for proximal femoral deformities in children with cerebral palsy (CP), subject-specific musculoskeletal models are needed. Non-rigid deformation (NRD) deforms generic onto personalized bone geometry and thereby transforms the muscle points. The goal of this study was to determine to what extent the models and simulation outcomes in CP patients differ when including subject-specific detail using NRD or Magnetic Resonance Imaging (MRI)-based models. The NRD models slightly overestimated hip contact forces compared to MRI models and differences in muscle point positions and moment arm lengths (MALs) remained, although differences were smaller than for the generic model. 相似文献
72.
Jennifer M. Cramer Rita C. G. Mesquita Tony Vizcarra Bentos Barry Moser G. Bruce Williamson 《Biotropica》2007,39(6):709-718
Fragmentation that alters mutualistic relationships between plants and frugivorous animals may reduce the seed dispersal of trees. We examined the effects of forest fragmentation on the distributions of seeds and seedlings of a Central Amazon endemic tree, Duckeodendron cestroides . In the dry seasons of 2002–2004, seeds and first-year seedlings were counted within wedge-shaped transects centered around Duckeodendron adults in fragments and nearby continuous forests at the Biological Dynamics of Forest Fragmentation Project. Analyses showed that fragmentation reduced seed dispersal quantity and quality. The percent and distance of dispersed seeds were both twice as great in continuous forest as in fragments. The distances of each tree's five furthest dispersed seeds were three times greater in continuous forest than fragments. Over the 3-yr study, 20 times more seeds were dispersed more than 10 m from parent crowns in continuous forest than fragments. A regression analysis showed more dispersed seeds at all distances in continuous forest than fragments. Dispersal differences were strong in 2002 and 2004, years of large fruit crops, but weak or absent in 2003, when fruit production was low. As distance from parent crowns increased, the number of seedlings declined more rapidly in fragments than continuous forest. Distance-dependent mortality between the seed and seedling stages appeared to be more important in continuous forest than fragments. This research provides ample, indirect evidence demonstrating that forest fragmentation can result in the breakdown of a seed dispersal mutualism, potentially jeopardizing the reproduction of a rare, tropical tree. 相似文献
73.
Cappuyns AM Bernaerts K Smets IY Ona O Prinsen E Vanderleyden J Van Impe JF 《Biotechnology progress》2007,23(5):1074-1081
In this paper the problem of reliable and accurate parameter estimation for unstructured models is considered. It is illustrated how a theoretically optimal design can be successfully translated into a practically feasible, robust, and informative experiment. The well-known parameter estimation problem of Monod kinetic parameters is used as a vehicle to illustrate our approach. As known for a long time, noisy batch measurements do not allow for unique and accurate estimation of the kinetic parameters of the Monod model. Techniques of optimal experiment design are, therefore, exploited to design informative experiments and to improve the parameter estimation accuracy. During the design process, practical feasibility has to be kept in mind. The designed experiments are easy to implement in practice and do not require additional monitoring equipment. Both design and experimental validation of informative fed batch experiments are illustrated with a case study, namely, the growth of the nitrogen-fixing bacteria Azospirillum brasilense. 相似文献
74.
Snchez-Reyes Ayixon Bretn-Deval Luz Mangelson Hayley Salinas-Peralta Ilse Sanchez-Flores Alejandro 《International microbiology》2022,25(1):99-110
International Microbiology - Microbial biodiversity is represented by a variety of genomic landscapes adapted to dissimilar environments on Earth. These genomic landscapes contain functional... 相似文献
75.
Moser Florian N. van Rijssel Jacco C. Ngatunga Benjamin Mwaiko Salome Seehausen Ole 《Hydrobiologia》2019,832(1):283-296
Hydrobiologia - Cichlids of the genus Oreochromis (“Tilapias”) are intensively used in aquaculture around the world. In many cases, when “Tilapia” were introduced for... 相似文献
76.
Van Den Herrewegen Yana Denewet Lissa Buckinx An Albertini Giulia Van Eeckhaut Ann Smolders Ilse De Bundel Dimitri 《Neurochemical research》2019,44(3):600-608
Neurochemical Research - Temporal lobe epilepsy (TLE) is an acquired form of focal epilepsy, in which patients not only suffer from unprovoked, devastating seizures, but also from severe... 相似文献
77.
78.
Sharon A. Poessel David M. Barnard Cara Applestein Matthew J. Germino Ethan A. Ellsworth Don Major Ann Moser Todd E. Katzner 《Ecology and evolution》2022,12(3)
Habitat loss is the most prevalent threat to biodiversity in North America. One of the most threatened landscapes in the United States is the sagebrush (Artemisia spp.) ecosystem, much of which has been fragmented or converted to non‐native grasslands via the cheatgrass‐fire cycle. Like many sagebrush obligates, greater sage‐grouse (Centrocercus urophasianus) depend upon sagebrush for food and cover and are affected by changes to this ecosystem. We investigated habitat selection by 28 male greater sage‐grouse during each of 3 years after a 113,000‐ha wildfire in a sagebrush steppe ecosystem in Idaho and Oregon. During the study period, seeding and herbicide treatments were applied for habitat restoration. We evaluated sage‐grouse responses to vegetation and post‐fire restoration treatments. Throughout the 3 years post‐fire, sage‐grouse avoided areas with high exotic annual grass cover but selected strongly for recovering sagebrush and moderately strongly for perennial grasses. By the third year post‐fire, they preferred high‐density sagebrush, especially in winter when sagebrush is the primary component of the sage‐grouse diet. Sage‐grouse preferred forb habitat immediately post‐fire, especially in summer, but this selection preference was less strong in later years. They also selected areas that were intensively treated with herbicide and seeded with sagebrush, grasses, and forbs, although these responses varied with time since treatment. Wildfire can have severe consequences for sagebrush‐obligate species due to loss of large sagebrush plants used for food and for protection from predators and thermal extremes. Our results show that management efforts, including herbicide application and seeding of plants, directed at controlling exotic annual grasses after a wildfire can positively affect habitat selection by sage‐grouse. 相似文献
79.
Ilse Stevens Veerle Janssens Ellen Martens Stephen Dilworth Jozef Goris Christine Van Hoof 《European journal of biochemistry》2003,270(2):376-387
Protein phosphatase 2A is a phosphoserine/threonine phosphatase implicated in many cellular processes. The core enzyme comprises a catalytic and a PR65/A-subunit. The substrate specificity and subcellular localization are determined by a third regulatory B-subunit (PR55/B, PR61/B' and PR72/130/B"). To identify the proteins of the B" family in Xenopus laevis oocytes, a prophase Xenopus oocyte cDNA library was screened using human PR130 cDNA as a probe. Three different classes of cDNAs were isolated. One class is very similar to human PR130 and is probably the Xenopus orthologue of PR130 (XPR130). A second class of clones (XN73) is identical to the N-terminal part of XPR130 but ends a few amino acids downstream of the putative splicing site of PR130. To investigate how this occurs, the genomic structure of the human PR130 gene was determined. This novel protein does not act as a PP2A subunit but might compete with the function of PR130. The third set of clones (XPR70) is very similar to human PR48 but has an N-terminal extension. Further analysis of the human EST-database and the human PR48 gene structure, revealed that the human PR48 clone published is incomplete. The Xenopus orthologue of PR48 encodes a protein of 70 kDa which like the XPR130, interacts with the A-subunit in GST pull-down assays. XPR70 is ubiquitously expressed in adult tissues and oocytes whereas expression of XPR130 is very low in brain and oocytes. Expression of XN73 mainly parallels XPR130 with the exception of the brain. 相似文献
80.
Ilse C. E. Hendriksen Juliet Mwanga-Amumpaire Lorenz von Seidlein George Mtove Lisa J. White Rasaq Olaosebikan Sue J. Lee Antoinette K. Tshefu Charles Woodrow Ben Amos Corine Karema Somporn Saiwaew Kathryn Maitland Ermelinda Gomes Wirichada Pan-Ngum Samwel Gesase Kamolrat Silamut Hugh Reyburn Sarah Joseph Kesinee Chotivanich Caterina I. Fanello Nicholas P. J. Day Nicholas J. White Arjen M. Dondorp 《PLoS medicine》2012,9(8)