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1.
Towards a Better Prediction of Cell Settling on Nanostructure Arrays—Simple Means to Complicated Ends
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Nina Buch‐Månson Sara Bonde Jessica Bolinsson Trine Berthing Jesper Nygård Karen L. Martinez 《Advanced functional materials》2015,25(21):3246-3255
Vertical arrays of nanostructures (NSs) are emerging as promising platforms for probing and manipulating live mammalian cells. The broad range of applications requires different types of interfaces, but cell settling on NS arrays is not yet fully controlled and understood. Cells are both seen to deform completely into NS arrays and to stay suspended like tiny fakirs, which have hitherto been explained with differences in NS spacing or density. Here, a better understanding of this phenomenon is provided by using a model that takes into account the extreme membrane deformation needed for a cell to settle into a NS array. It is shown that, in addition to the NS density, cell settling depends strongly on the dimensions of the single NS, and that the settling can be predicted for a given NS array geometry. The predictive power of the model is confirmed by experiments and good agreement with cases from the literature. Furthermore, the influence of cell‐related parameters is evaluated theoretically and a generic method of tuning cell settling through surface coating is demonstrated experimentally. These findings allow a more rational design of NS arrays for the numerous exciting biological applications where the mode of cell settling is crucial. 相似文献
2.
Xiaopeng Yue Yongjian Xu Nina Gou Hongkui Li 《Polymer-Plastics Technology and Engineering》2015,54(6):639-646
A long fatty side chain was introduced into the macromolecule of hydroxyethyl cellulose (HEC) via esterification reaction. The hydrophobicity of hydroxyethyl cellulose lauric acid ester (HECLAE) was enhanced in comparison with HEC. The obtained HECLAE was used as macromolecular coupling agent in poly (butylene succinate)/wood flour composites and exhibited a positive influence on improving the mechanical performance of composites. Besides, HECLAE plays a role as a hydrophobic agent in composites. A significant increase in storage modulus (E’) was observed upon the incorporation of treated wood flour. SEM images showed that the dispersion of treated wood flour in PBS matrix was improved. 相似文献
3.
Nina Georgieva Kostova Elka Kraleva Alla A. Spojakina Erika Godocikova Peter Balaz 《Journal of Materials Science》2007,42(10):3321-3325
The Al-MCM-41 has been used as support to prepare Mo-containing catalysts. The 12- molybdophosphoric heteropoly acid (HPMo)
is used as initial compound. The catalysts are synthesized by two different methods: incipient impregnation with aqueous solution
of the acid and mechanochemical synthesis. The samples were tested in the reaction of the thiophene hydrodesulfurization after
activation with mixture H2 + H2S. The effect of the preparation method of the catalysts on their physicochemical and catalytic properties has been studied.
A partial destruction of the loaded compound is observed in mechanochemically treated sample whereas the aggregates are formed
from the particles of different size in the impregnated sample. The specific surface area of the sample prepared by mechanical–chemical
treatment decreases 2–3 times, while the total pore volume is about four times lower. The HDS activity is higher on the impregnated
sample than on the mechanochemically treated one. 相似文献
4.
5.
It is shown that steady-state kinetic data do not allow the discrimination between the redox and associated mechanisms of the partial oxidation reactions. A discrimination between these mechanisms was performed using transient experiments. The obtained rate expressions are in agreement with experimental kinetic data for catalytic partial oxidation of o-xylene.
An influence of the conjugate oxidation of a catalyst surface on dynamics and kinetics of the heterogeneous catalytic oxidative reactions is considered. Computing simulation of methane oxidative coupling of methane reaction at lowered temperature and elevated pressure has been performed. It showed that the reaction order with respect to oxygen exceeding unity is consistent with the chain branching mechanism of the reaction in the presence of TiSi2 and TiB2 and showed the important role of the branching chain cycles in the low-temperature OCM reaction at elevated pressure. 相似文献
6.
A meta-analysis that combined 33 correlations from 17 studies found a corrected average correlation of .330 between absence and turnover. The type of absence measure did not moderate the covariation between absence and turnover, but industry type and study duration did act as moderators. The results are discussed in the context of the "withdrawal" approach to understanding employee behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
The clinical consequences of single or multiple exposure of pregnant gilts to porcine reproductive and respiratory syndrome virus (PRRSV) at various stages of gestation were determined. Thirty-three pregnant gilts were allotted to 6 experimental groups (5 to 7 gilts/group). Gilts of groups 1 to 5 were exposed to strain NADC-8 of PRRSV at the following times: group 1, gestation day (GD) 1; group 2, GDs 1 and 90; group 3, GD 30; group 4, GDs 30 and 90; group 5, GD 90. Virus exposure was by either intrauterine (GD 1) or oronasal (GDs 30 and 90) inoculation. Gilts of group 6 were kept as nonexposed controls. Gilts were either necropsied on or about GD 111 (groups 1 to 5) or were allowed to farrow (group 6). The detection of PRRSV in serum of fetuses and piglets (within 12 hof birth) was considered evidence of transplacental infection. Transplacental infection and virus-induced death were and were not confirmed for groups 3, 4, and 5 and for groups 1, 2, and 6, respectively. Collectively, the results indicated that intrauterine exposure to PRRSV at GD 1 was without clinical effect (groups 1 and 2) and provided protection against subsequent exposure to the same strain of virus at GD 90 (group 2). The highest incidence of transplacental infection and fetal death followed a single exposure to PRRSV at GD 90 (group 5). 相似文献
8.
Celin Gürler Mathias Feyen Silke Behrens Nina Matoussevitch Annette M. Schmidt 《Polymer》2008,49(9):2211-2216
Much effort is conducted to construct artificial objects that are capable of converting chemical or electromagnetic energy into a specific, predetermined motion on the nanoscale. We present results on the synthesis of core–shell nanoparticles capable to be set in rotation by the application of electromagnetic fields. The nanorotors implied in the study are based on the cobalt nanospheres decorated with a stabilizing brush shell composed of poly(?-caprolactone) that is attached by surface-initiated polymerization. The functional cores used as macroinitiators can be fabricated alternatively by a two-step or a one-step process. 相似文献
9.
Examines ritual as a tool for psychotherapeutic application with clients experiencing grief, trauma, anxiety, and family dysfunction. Case vignettes are provided to illustrate the therapeutic properties and creative power of rituals as interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Katarzyna Jasieniecka-Gazarkiewicz Kamil Demski Satinder K. Gidda Sylwia Kliska Janusz Niedojado Ida Lager Anders S. Carlsson Elena A. Minina Robert T. Mullen Peter V. Bozhkov Sten Stymne Antoni Bana 《International journal of molecular sciences》2021,22(6)
Arabidopsis thaliana possesses two acyl-CoA:lysophosphatidylethanolamine acyltransferases, LPEAT1 and LPEAT2, which are encoded by At1g80950 and At2g45670 genes, respectively. Both single lpeat2 mutant and double lpeat1 lpeat2 mutant plants exhibit a variety of conspicuous phenotypes, including dwarfed growth. Confocal microscopic analysis of tobacco suspension-cultured cells transiently transformed with green fluorescent protein-tagged versions of LPEAT1 or LPEAT2 revealed that LPEAT1 is localized to the endoplasmic reticulum (ER), whereas LPEAT2 is localized to both Golgi and late endosomes. Considering that the primary product of the reaction catalyzed by LPEATs is phosphatidylethanolamine, which is known to be covalently conjugated with autophagy-related protein ATG8 during a key step of the formation of autophagosomes, we investigated the requirements for LPEATs to engage in autophagic activity in Arabidopsis. Knocking out of either or both LPEAT genes led to enhanced accumulation of the autophagic adaptor protein NBR1 and decreased levels of both ATG8a mRNA and total ATG8 protein. Moreover, we detected significantly fewer membrane objects in the vacuoles of lpeat1 lpeat2 double mutant mesophyll cells than in vacuoles of control plants. However, contrary to what has been reported on autophagy deficient plants, the lpeat mutants displayed a prolonged life span compared to wild type, including delayed senescence. 相似文献