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排序方式: 共有1773条查询结果,搜索用时 140 毫秒
1.
Macintosh Katrina A. McDowell Richard W. Wright-Stow Aslan E. Depree Craig Robinson Guy M. 《Nutrient Cycling in Agroecosystems》2021,120(2):121-129
Nutrient Cycling in Agroecosystems - Reducing agriculturally derived diffuse contaminant losses (via non-point sources) from land to water has proven difficult for decades. Owing to the diversity... 相似文献
2.
Rebecca L. Walton Michael J. Brova Beecher H. Watson Elizabeth R. Kupp Mark A. Fanton Richard J. Meyer Gary L. Messing 《Journal of the European Ceramic Society》2021,41(3):1945-1953
Direct writing is a unique means to align anisotropic particles for the fabrication of textured ceramics by templated grain growth (TGG). We show that alignment of tabular barium titanate (BT) template particles (20–40 μm width and 0.5–2 μm thickness) in a PIN-PMN-PT matrix powder (d50 = 280 nm) is significantly improved during direct writing using anisotropic nozzles at high printing rates. The particle orientation distribution in as-printed filaments, and the texture orientation distribution in sintered ceramic filaments are shown to directly correlate with COMSOL Multiphysics-predicted torque distributions for direct writing with aspect ratio 2, 3 and 5 oval nozzles. Electromechanical strain properties of the textured piezoelectric ceramics significantly improved relative to random ceramics when printed with anisotropic nozzles. Simulations of aspect ratio 20 nozzles and nozzles with interior baffles demonstrate significantly increased torque and near elimination of constant shear stress cores (i.e. plug flow). 相似文献
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4.
Rebecca L. Tarnopol Sierra Bowden Kevin Hinkle Krithika Balakrishnan Akira Nishii Caleb J. Kaczmarek Tara Pawloski Dr. Anthony G. Vecchiarelli 《Chembiochem : a European journal of chemical biology》2019,20(20):2535-2545
One of the primary challenges facing synthetic biology is reconstituting a living system from its component parts. A particularly difficult landmark is reconstituting a self-organizing system that can undergo autonomous chromosome compaction, segregation, and cell division. Here, we discuss how the syn3.0 minimal genome can inform us of the core self-organizing principles of a living cell and how these self-organizing processes can be built from the bottom up. The review underscores the importance of fundamental biology in rebuilding life from its molecular constituents. 相似文献
5.
Ivie L. Conlon Dr. Brandon Drennen Dr. Maryanna E. Lanning Samuel Hughes Rebecca Rothhaas Dr. Paul T. Wilder Dr. Alexander D. MacKerell Jr. Dr. Steven Fletcher 《ChemMedChem》2020,15(18):1691-1698
Protein–protein interactions (PPIs), many of which are dominated by α-helical recognition domains, play key roles in many essential cellular processes, and the dysregulation of these interactions can cause detrimental effects. For instance, aberrant PPIs involving the Bcl-2 protein family can lead to several diseases including cancer, neurodegenerative diseases, and diabetes. Interactions between Bcl-2 pro-life proteins, such as Mcl-1, and pro-death proteins, such as Bim, regulate the intrinsic pathway of apoptosis. p53, a tumor-suppressor protein, also has a pivotal role in apoptosis and is negatively regulated by its E3 ubiquitin ligase HDM2. Both Mcl-1 and HDM2 are upregulated in numerous cancers, and, interestingly, there is crosstalk between both protein pathways. Recently, synergy has been observed between Mcl-1 and HDM2 inhibitors. Towards the development of new anticancer drugs, we herein describe a polypharmacology approach for the dual inhibition of Mcl-1 and HDM2 by employing three densely functionalized isoxazoles, pyrazoles, and thiazoles as mimetics of key α-helical domains of their partner proteins. 相似文献
6.
The impact of total solid (TS) content in combination with the feed rate and air inlet temperature on the survival of Lactobacillus paracasei ssp. paracasei F19 after spray drying in a skim milk matrix has been investigated and correlated with the capsule size. Depending on the experimental conditions, the survival rates ranged from 64 to 0.2%. The higher the air inlet temperature, the lower was the survival rate and an inversely correlation between the TS content and particle size has been determined. These results clearly indicate that process stress analyses and product-related characteristics must not be regarded separately. 相似文献
7.
Rebecca Brannon Katharin Jensen Debasish Nayak 《Journal of the European Ceramic Society》2018,38(8):2971-2987
Even if a ceramic's homogenized properties (such as anisotropically evolving stiffness) truly can be predicted from complete knowledge of sub-continuum morphology (e.g., locations, sizes, shapes, orientations, and roughness of trillions of crystals, dislocations, impurities, pores, inclusions, and/or cracks), the necessary calculations are untenably hypervariate. Non-productive (almost derailing) debates over shortcomings of various first-principles ceramics theories are avoided in this work by discussing numerical coarsening in the context of a pedagogically appealing buckling foundation model that requires only sophomore-level understanding of springs, buckling hinges, dashpots, etc. Bypassing pre-requisites in constitutive modeling, this work aims to help students to understand the difference between damage and plasticity while also gaining experience in Monte-Carlo numerical optimization via scale-bridging that reduces memory and processor burden by orders of magnitude while accurately preserving aleatory (finite-sampling) perturbations that are crucial to accurately predict bifurcations, such as ceramic fragmentation. 相似文献
8.
Rebecca C. Feiner Isabell Kemker Lea Krutzke Ellen Allmendinger Daniel J. Mandell Norbert Sewald Stefan Kochanek Kristian M. Müller 《International journal of molecular sciences》2020,21(24)
The epidermal growth factor receptor (EGFR) plays a central role in the progression of many solid tumors. We used this validated target to analyze the de novo design of EGFR-binding peptides and their application for the delivery of complex payloads via rational design of a viral vector. Peptides were computationally designed to interact with the EGFR dimerization interface. Two new peptides and a reference (EDA peptide) were chemically synthesized, and their binding ability characterized. Presentation of these peptides in each of the 60 capsid proteins of recombinant adeno-associated viruses (rAAV) via a genetic based loop insertion enabled targeting of EGFR overexpressing tumor cell lines. Furthermore, tissue distribution and tumor xenograft specificity were analyzed with systemic injection in chicken egg chorioallantoic membrane (CAM) assays. Complex correlations between the targeting of the synthetic peptides and the viral vectors to cells and in ovo were observed. Overall, these data demonstrate the potential of computational design in combination with rational capsid modification for viral vector targeting opening new avenues for viral vector delivery and specifically suicide gene therapy. 相似文献
9.
Ethan S. Pickerill Rebecca P. Kurtz Aaron Tharp Paula Guerrero Sanz Munni Begum Douglas A. Bernstein 《Yeast (Chichester, England)》2019,36(11):669-677
RNA can be modified in over 100 distinct ways, and these modifications are critical for function. Pseudouridine synthases catalyse pseudouridylation, one of the most prevalent RNA modifications. Pseudouridine synthase 7 modifies a variety of substrates in Saccharomyces cerevisiae including tRNA, rRNA, snRNA, and mRNA, but the substrates for other budding yeast Pus7 homologues are not known. We used CRISPR-mediated genome editing to disrupt Candida albicans PUS7 and find absence leads to defects in rRNA processing and a decrease in cell surface hydrophobicity. Furthermore, C. albicans Pus7 absence causes temperature sensitivity, defects in filamentation, altered sensitivity to antifungal drugs, and decreased virulence in a wax moth model. In addition, we find C. albicans Pus7 modifies tRNA residues, but does not modify a number of other S. cerevisiae Pus7 substrates. Our data suggests C. albicans Pus7 is important for fungal vigour and may play distinct biological roles than those ascribed to S. cerevisiae Pus7. 相似文献
10.
Michael J. Brova Beecher H. Watson III Rebecca L. Walton Elizabeth R. Kupp Mark A. Fanton Richard J. Meyer Jr. Gary L. Messing 《Journal of the American Ceramic Society》2020,103(9):4794-4802
This study explores sintering and piezoelectricity of ZnO-doped perovskite Pb(In1/2Nb1/2)O3-Pb(Zn1/3Nb2/3)O3-PbTiO3 (PIN-PZN-PT) ceramics. The enhanced densification of ZnO-doped PIN-PZN-PT is attributed to the formation of oxygen vacancies by the incorporation of Zn2+ into the perovskite B-site and increased rate of bulk diffusion relative to undoped PIN-PZN-PT. Incorporation of Zn2+ into the perovskite lattice increased the tetragonal character of PIN-PZN-PT as demonstrated by tetragonal peak splitting and increased Curie temperature. Sintering in flowing oxygen reduced the solubility of Zn2+ in the perovskite lattice and resulted in rhombohedral PIN-PZN-PT. Sintering in oxygen prevented secondary phase formation which resulted in a high-piezoelectric coefficient (d33 – 550 pC/N), high-coercive field (Ec – 13 kV/cm), and high-rhombohedral to tetragonal phase transition temperature (Tr-t – 165°C). We conclude that ZnO-doped PIN-PZN-PT ceramics are excellent candidates for high-power transducer applications. 相似文献