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排序方式: 共有9169条查询结果,搜索用时 19 毫秒
31.
Francesco Scolari Elisa Delbarba Domenico Santoro Loreto Gesualdo Antonello Pani Nadia Dallera Laila-Yasmin Mani Marisa Santostefano Sandro Feriozzi Marco Quaglia Giuliano Boscutti Angelo Ferrantelli Carmelita Marcantoni Patrizia Passerini Riccardo Magistroni Federico Alberici Gian Marco Ghiggeri Claudio Ponticelli Pietro Ravani for the RI-CYCLO Investigators 《Journal of the American Society of Nephrology : JASN》2021,32(4):972
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A Quantitative Comparison of Physical Accuracy and Numerical Stability of Lattice Boltzmann Color Gradient and Pseudopotential Multicomponent Models for Microfluidic Applications 下载免费PDF全文
Karun P. N. Datadien Gianluca Di Staso Herman M. A. Wijshoff & Federico Toschi 《Communications In Computational Physics》2022,32(2):450-489
The performances of the Color-Gradient (CG) and the Shan-Chen (SC) multicomponent Lattice Boltzmann models are quantitatively compared side-by-side on
multiple physical flow problems where breakup, coalescence and contraction of fluid
ligaments are important. The flow problems are relevant to microfluidic applications,
jetting of microdroplets as seen in inkjet printing, as well as emulsion dynamics. A
significantly wider range of parameters is shown to be accessible for CG in terms of
density-ratio, viscosity-ratio and surface tension values. Numerical stability for a high
density ratio $\mathcal{O}(1000)$ is required for simulating the drop formation process during
inkjet printing which we show here to be achievable using the CG model but not using
the SC model. Our results show that the CG model is a suitable choice for challenging
simulations of droplet formation, due to a combination of both numerical stability and
physical accuracy. We also present a novel approach to incorporate repulsion forces
between interfaces for CG, with possible applications to the study of stabilized emulsions. Specifically, we show that the CG model can produce similar results to a known
multirange potentials extension of the SC model for modelling a disjoining pressure,
opening up its use for the study of dense stabilized emulsions. 相似文献
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Atteeq U. Rehman Maryam Najafi Marios Kambouris Lihadh Al‐Gazali Periklis Makrythanasis Abolfazl Rad Reza Maroofian Anna Rajab Zornitza Stark Jill V. Hunter Zeineb Bakey Mari J. Tokita Weimin He Francesco Vetrini Andrea Petersen Federico A. Santoni Hanan Hamamy Kaman Wu Fatma Al‐Jasmi Martin Helmstdter Sebastian J. Arnold Fan Xia Christopher Richmond Pengfei Liu Ehsan Ghayoor Karimiani GholamReza Karami Madani Sebastian Lunke Hatem El‐Shanti Christine M. Eng Stylianos E. Antonarakis Jozef Hertecant Magdalena Walkiewicz Yaping Yang Miriam Schmidts 《Human mutation》2019,40(3):267-280
Next‐generation sequencing (NGS) has been instrumental in solving the genetic basis of rare inherited diseases, especially neurodevelopmental syndromes. However, functional workup is essential for precise phenotype definition and to understand the underlying disease mechanisms. Using whole exome (WES) and whole genome sequencing (WGS) in four independent families with hypotonia, neurodevelopmental delay, facial dysmorphism, loss of white matter, and thinning of the corpus callosum, we identified four previously unreported homozygous truncating PPP1R21 alleles: c.347delT p.(Ile116Lysfs*25), c.2170_2171insGGTA p.(Ile724Argfs*8), c.1607dupT p.(Leu536Phefs*7), c.2063delA p.(Lys688Serfs*26) and found that PPP1R21 was absent in fibroblasts of an affected individual, supporting the allele's loss of function effect. PPP1R21 function had not been studied except that a large scale affinity proteomics approach suggested an interaction with PIBF1 defective in Joubert syndrome. Our co‐immunoprecipitation studies did not confirm this but in contrast defined the localization of PPP1R21 to the early endosome. Consistent with the subcellular expression pattern and the clinical phenotype exhibiting features of storage diseases, we found patient fibroblasts exhibited a delay in clearance of transferrin‐488 while uptake was normal. In summary, we delineate a novel neurodevelopmental syndrome caused by biallelic PPP1R21 loss of function variants, and suggest a role of PPP1R21 within the endosomal sorting process or endosome maturation pathway. 相似文献
36.
Federico Quinzi Marika Berchicci Valentina Bianco Rinaldo Livio Perri Francesco Di Russo 《Psychophysiology》2019,56(3)
The Bereitschaftspotential (BP) and the P3 are well‐known ERPs usually observed during self‐paced and externally triggered tasks. Recently, the BP was also detected in externally triggered tasks before stimulus onset. However, doubts have been raised about the authenticity of the BP in these tasks due to possible overlaps with the previous trial P3 (hereinafter s‐1 P3). Here, we aim to test the authenticity of the BP in externally triggered tasks by comparing ERPs obtained during two visuomotor response tasks with different interstimulus intervals (ISIs) allowing (short‐ISI; 1,000–2,000 ms) or not (long‐ISI; 2,000–4,000 ms) P3‐BP overlaps. In line with previous research, we hypothesize that BP and the s‐1 P3 contribute independently to the scalp‐detected activities during these tasks. ERPs were recorded from 14 healthy participants during the short‐ISI and long‐ISI visuomotor response tasks. Amplitudes and latencies of pre‐ (BP and pN) and poststimulus ERP components (P1, pN1, pP1, N1, pP2, dpP2, N2, P3) were compared between conditions. No effect of ISI was found on the amplitude of any pre‐ and poststimulus components. In contrast, longer ISI is associated with earlier onsets of the BP and pN components. In visuomotor response tasks, the BP is independent from the P3 elicited by the previous trial (s‐1 P3), even using relatively short ISI. Since the different ISIs did not affect the amplitude of the BP and the P3 components, we conclude that also a short ISI can be adopted safely and conveniently to keep a reasonable duration of the overall experiment. 相似文献
37.
Guido N. Buezas Federico Becerra Alejandra I. Echeverría Adrin Cisilino Aldo I. Vassallo 《Journal of anatomy》2019,234(4):564-575
The monophyletic group Caviomorpha constitutes the most diverse rodent clade in terms of locomotion, ecology and diet. Caviomorph species show considerable variation in cranio‐mandibular morphology that has been linked to the differences in toughness of dietary items and other behaviors, such as chisel‐tooth digging. This work assesses the structural strength of the mandible of three caviomorph species that show remarkable differences in ecology, behavior and bite force: Chinchilla lanigera (a surface‐dwelling species), Octodon degus (a semi‐fossorial species) and Ctenomys talarum (a subterranean species). Finite element (FE) models of the mandibles are used to predict the stresses they withstand during incisor biting; the results are related to in vivo bite forces and interspecific variations in the mandibular geometries. The study concludes that the mandible of C. talarum is better able to withstand strong incisor bites. Its powerful adducting musculature is consistent with the notorious lateral expansion of the angular process and the masseteric crest, and the enhanced cortical bone thickness. Although it has a relatively low bite force, the mandible of O. degus also shows a good performance for mid‐to‐strong incisor biting, in contrast to that of C. lanigera, which exhibits, from a mechanical point of view, the worst performance. The mandibles of C. talarum and O. degus appear to be better suited to withstand stronger reaction forces from incisor biting, which is consistent with their closer phylogenetic affinity and shared digging behaviors. The contrast between the low in vivo bite force of C. lanigera and the relatively high estimations that result from the models suggests that its adductor musculature could play significant roles in functions other than incisor biting. 相似文献
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Gladys Valencia-Castañeda Martin G. Frías-Espericueta Ruth C. Vanegas-Pérez Jesús A. Pérez-Ramírez María C. Chávez-Sánchez Federico Páez-Osuna 《Bulletin of environmental contamination and toxicology》2018,101(2):229-234
Shrimp farming in low salinities waters is an alternative to increasing production, and counteracting disease problems in brackish and marine waters. However, in low-salinity waters, toxicity of nitrogen compounds increases, and there is no available data of its acute toxicity in shrimp postlarvae. This study determined the acute toxicity of ammonia, nitrite and nitrate in Litopenaeus vannamei postlarvae in 1 and 3 g/L salinity, as well as the safety levels. The LC50 confirms that nitrite is more toxic than ammonia and nitrate in low salinity waters, and that its toxicity increases with a decrease in salinity. The safe levels estimated for salinities of 1 and 3 g/L were 0.54 and 0.81 mg/L for total ammonia–N, 0.17 and 0.25 mg/L for NO2–N, and 5.6 and 21.5 mg/L for NO3–N, respectively. 相似文献
40.
Sforza NM Franchini F Lamma A Botticelli S Ghigi G 《The International journal of periodontics & restorative dentistry》2007,27(6):589-595
The objective of the present study was to observe the effect of positioning of the mandible on the accuracy of cross-sectional images obtained by reformatting computerized tomographic (CT) scans. An additional aim was to evaluate the ability of a software program (DentalVox, Era Scientific) to reconstruct these measurements on the reformatted images, regardless of the positioning of the mandible, accurately and without distortion. The test was carried out by examining a partially edentulous dry human mandible with an acrylic radiologic template. Through the use of an acrylic glass support, the mandible was positioned at angles of 0, 10, 15, 20, and 30 degrees relative to the scanning gantry, and a series of CT scans was performed that provided five sets of axial images. Each set of original axial images was reformatted by the DentalVox software, used first in its basic function, which is typical of all software for axial CT measurement (control group), and again in its function of site-specific multiplanar reconstruction (test group). The results showed that the position of the mandible in relation to the CT gantry can influence the precision of the linear measurements. The error ranged from 2% to 51%. The DentalVox software allowed the reconstruction of cross-sectional images with very little distortion regardless of the mandibular position. 相似文献