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991.
992.
Hakiki Melanie Noamane Taarji Yiguo Zhao Nauman Khalid Marcos A. Neves Isao Kobayashi Ambo Tuwo Mitsutoshi Nakajima 《International Journal of Food Science & Technology》2020,55(1):211-221
In this study, seaweed polysaccharides (alginate and carrageenan) were modified with dodecenylsuccinic anhydride (DSA), and their stabilising properties in oil-in-water (O/W) emulsion system were evaluated. The physicochemical characteristics were determined by droplet size, interfacial tension and ζ-potential and structurally verified by Fourier transform infrared spectroscopy (FTIR). Both CRG-DSA and ALG-DSA applied in O/W emulsion system exhibited smaller droplet sizes over the increasing concentration and were more stable during storage than native ones. The ζ-potential of DSA-modified seaweed polysaccharides has more negative charge compared with their native forms, owing to the additional carboxyl groups from modification reaction. In addition, DSA-modified seaweed polysaccharides decreased the interfacial tension at soybean oil–water interface from 23.1 and 23.9 mN m−1 to 14.2 and 13.6 mN m−1, respectively. The successful modification reaction was confirmed by FTIR analysis. This study demonstrated that DSA-modified seaweed polysaccharides may serve as prospective emulsifiers in food, pharmaceutical and other industrial fields. 相似文献
993.
Vasiliki Panagiotidou Andreas Koerner Marcos Cruz Brenda Parker Bastian Beyer Sofoklis Giannakopoulos 《建筑学研究前沿(英文版)》2022,11(4):691-708
The conventional building material palette has been proven limited in terms of adaptability to our current environmental challenges. Innovations in computational design and digital manufacturing have supported the broadening of biomaterial applications as an alternative. While biomaterials are characteristically responsive to stimuli such as temperature and humidity, their unpredictable behaviour is a hurdle to standardization and architectural utilisation. To examine the nexus between material formulation, computation and manufacturing, multi-biomaterial lattice structures were produced through an environmentally informed workflow. Customized biomaterial development resulted in three candidate biopolymer blends with varying levels of hydro-responsiveness and transparency. The computational strategy included a machine learning clustering algorithm to customise results and dictate material distribution outputs. To test the workflow, environmental data of solar radiation exposure and solar heat gain from a specific location was used to inform the material deposition via pneumatic extrusion for the design and digital fabrication of a deformation-controlled prototype of 350 mm × 350 mm. This led to a series of multi-biomaterial wall panel components that can be applied at architectural scale. In future, these techniques can support the incorporation of living elements to be embedded within the built environment for truly animate architecture. 相似文献
994.
Davide Doni Leonardo Passerini Grard Audran Sylvain R. A. Marque Marvin Schulz Javier Santos Paola Costantini Marco Bortolus Donatella Carbonera 《International journal of molecular sciences》2020,21(24)
Frataxin is a highly conserved protein whose deficiency results in the neurodegenerative disease Friederich’s ataxia. Frataxin’s actual physiological function has been debated for a long time without reaching a general agreement; however, it is commonly accepted that the protein is involved in the biosynthetic iron-sulphur cluster (ISC) machinery, and several authors have pointed out that it also participates in iron homeostasis. In this work, we use site-directed spin labeling coupled to electron paramagnetic resonance (SDSL EPR) to add new information on the effects of ferric and ferrous iron binding on the properties of human frataxin in vitro. Using SDSL EPR and relating the results to fluorescence experiments commonly performed to study iron binding to FXN, we produced evidence that ferric iron causes reversible aggregation without preferred interfaces in a concentration-dependent fashion, starting at relatively low concentrations (micromolar range), whereas ferrous iron binds without inducing aggregation. Moreover, our experiments show that the ferrous binding does not lead to changes of protein conformation. The data reported in this study reveal that the currently reported binding stoichiometries should be taken with caution. The use of a spin label resistant to reduction, as well as the comparison of the binding effect of Fe2+ in wild type and in the pathological D122Y variant of frataxin, allowed us to characterize the Fe2+ binding properties of different protein sites and highlight the effect of the D122Y substitution on the surrounding residues. We suggest that both Fe2+ and Fe3+ might play a relevant role in the context of the proposed FXN physiological functions. 相似文献
995.
Austin J. Leitgeb Javier A. Feliciano Hugo A. Sanchez Ryan A. Allen Kelly R. Morrison Kyle J. Sommers Dr. Robert G. Carden Prof. William M. Wuest Prof. Kevin P. C. Minbiole 《ChemMedChem》2020,15(8):667-670
Thirty-six biscationic quaternary ammonium compounds were efficiently synthesized in one step to examine the effect of molecular geometry of two-carbon linkers on antimicrobial activity. The synthesized compounds showed strong antimicrobial activity against a panel of both Gram-positive and Gram-negative bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). While the linker geometry showed only a modest correlation with antimicrobial activity, several of the synthesized bisQACs are promising potential antiseptics due to good antimicrobial activity (MIC≤2 μM) and their higher therapeutic indices compared to previously reported QACs. 相似文献
996.
Armas Vega Esteban Alejandro González Fernández Edgar Sandoval Orozco Ana Lucila García Villalba Luis Javier 《Neural computing & applications》2021,33(10):4713-4727
Neural Computing and Applications - With the increasing number of software applications that allow altering digital images and their ease of use, they weaken the credibility of an image. This... 相似文献
997.
998.
Efficient code development for improving execution performance in high-performance computing centers
Corral-García Javier Lemus-Prieto Felipe Pérez-Toledano Miguel-Ángel 《The Journal of supercomputing》2021,77(4):3261-3288
The Journal of Supercomputing - Thanks to high-performance computing (HPC), it is possible to solve all kinds of highly complex projects from multiple scientific disciplines that require... 相似文献
999.
Javier Navarro-Zaragoza Lorena Cuenca-Bermejo Pilar Almela María-Luisa Laorden María-Trinidad Herrero 《International journal of molecular sciences》2021,22(6)
Small heat shock proteins (HSPs), such as HSP27, are ubiquitously expressed molecular chaperones and are essential for cellular homeostasis. The major functions of HSP27 include chaperoning misfolded or unfolded polypeptides and protecting cells from toxic stress. Dysregulation of stress proteins is associated with many human diseases including neurodegenerative diseases, such as Parkinson’s disease (PD). PD is characterized by the presence of aggregates of α-synuclein in the central and peripheral nervous system, which induces the degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and in the autonomic nervous system. Autonomic dysfunction is an important non-motor phenotype of PD, which includes cardiovascular dysregulation, among others. Nowadays, the therapies for PD focus on dopamine (DA) replacement. However, certain non-motor symptoms with a great impact on quality of life do not respond to dopaminergic drugs; therefore, the development and testing of new treatments for non-motor symptoms of PD remain a priority. Since small HSP27 was shown to prevent α-synuclein aggregation and cytotoxicity, this protein might constitute a suitable target to prevent or delay the motor and non-motor symptoms of PD. In the first part of our review, we focus on the cardiovascular dysregulation observed in PD patients. In the second part, we present data on the possible role of HSP27 in preventing the accumulation of amyloid fibrils and aggregated forms of α-synuclein. We also include our own studies, highlighting the possible protective cardiac effects induced by L-DOPA treatment through the enhancement of HSP27 levels and activity. 相似文献
1000.
Francisco Maciel Monticeli Dielly Cavalcanti da Silva Monte Vidal Marcos Yutaka Shiino Herman Jacobus Cornelis Voorwald Maria Odila Hilrio Cioffi 《Polymer Engineering and Science》2019,59(6):1215-1222
The mechanical properties of composite structures depend on the preform impregnation and a successful impregnation can be achieved using the permeability relation in the case of an infusion process. The objective of this study is to develop an analytical model to predict the permeability K of carbon and glass fabrics through hybrid laminate using different stacking sequence, applying an average‐permeability model. Preforms permeabilities were evaluated through tortuosity and void‐volume fraction. The model allows the analysis of different stacking sequence combinations (interleaved and in block), measuring the contribution of each material type. As a result, hybrid average‐permeability model was validated through experimental permeability tests, dimensionless permeability, and tortuosity results, besides enabling predictions of the flow front behavior with <10% of deviation. Carbon fiber preforms exhibited higher flow resistance, which is explained via tortuosity concept. A combination of carbon/glass preforms presented an increased permeability, which means a synergy that provides higher value of K. In addition, the use of hybrid preforms, especially Hybrid 2 stacking sequence, reduce the injection time and void formation, ensuring composite impregnation quality. POLYM. ENG. SCI., 59:1215–1222 2019. © 2019 Society of Plastics Engineers 相似文献