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101.
Francesco Molinari Raffaella Villa Fabrizio Aragozzini Paolo Cabella Massimo Barbeni Francesco Squarcia 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,70(3):294-298
Acetobacter pasteurianus NCIMB 11664 was selected for multigram-scale production of different aliphatic carboxylic acids through oxidation of the corresponding alcohols after screening different acetic acid bacteria. Continuous production was carried out using an air-lift reactor, with overall yields of 1-propionic, 1-butyric, 2-methyl-1-butyric and 3-methyl-1-butyric acids ranging from 45 to 61 g dm−3. ©1997 SCI 相似文献
102.
Sadia Perveen Daniela Rossin Emanuela Vitale Rachele Rosso Roberto Vanni Caterina Cristallini Raffaella Rastaldo Claudia Giachino 《International journal of molecular sciences》2021,22(23)
Myocardial infarction (MI) is one of the leading causes of heart-related deaths worldwide. Following MI, the hypoxic microenvironment triggers apoptosis, disrupts the extracellular matrix and forms a non-functional scar that leads towards adverse left ventricular (LV) remodelling. If left untreated this eventually leads to heart failure. Besides extensive advancement in medical therapy, complete functional recovery is never accomplished, as the heart possesses limited regenerative ability. In recent decades, the focus has shifted towards tissue engineering and regenerative strategies that provide an attractive option to improve cardiac regeneration, limit adverse LV remodelling and restore function in an infarcted heart. Acellular scaffolds possess attractive features that have made them a promising therapeutic candidate. Their application in infarcted areas has been shown to improve LV remodelling and enhance functional recovery in post-MI hearts. This review will summarise the updates on acellular scaffolds developed and tested in pre-clinical and clinical scenarios in the past five years with a focus on their ability to overcome damage caused by MI. It will also describe how acellular scaffolds alone or in combination with biomolecules have been employed for MI treatment. A better understanding of acellular scaffolds potentialities may guide the development of customised and optimised therapeutic strategies for MI treatment. 相似文献
103.
Andrea Fischli Stefanie R. Schmid Raffaella Coppolecchia Patrick Linder 《Yeast (Chichester, England)》1996,12(10):977-981
We have isolated a cDNA clone encoding eIF4A from Schizosaccharomyces pombe. The deduced protein sequence is similar in length and sequence to other eIF4A proteins and exhibits highest similarity with the mammalian eIF4A protein. Hybridization with genomic DNA reveals two eIF4A genes located on two different chromosomes. This sequence has been deposited in the EMBL Data Library under Accession Number X80796. 相似文献
104.
Marta Invernizzi Raffaella Suriano Allegra Muscatello Stefano Turri Marinella Levi 《应用聚合物科学杂志》2020,137(5):48333
In this work, a newly prepared cationic/free-radical photopolymer, which consists of two epoxies and a tetrafunctional acrylate, is presented for the first time for a visible light stereolithography (SL), showing the advantages of both cationic and free-radical resins. An onium salt, commonly used as a cationic UV initiator, and a photosensitizer make the blend suitable for a near-visible (405 nm) SL. An increase in the polymerization rate and a drop in the induction period are observed for the newly prepared cationic/free-radical blend, compared with either only cationic systems or free-radical resins. This suggests that the combination of cationic and free-radical polymerizations in a single resin has a positive synergistic effect. The addition of silica nanoparticles to the blend provides a reinforcing and toughening effect. Indeed, the resin loaded with silica shows a 31% increase in the elastic modulus, compared with the unfilled resin. Regarding the values of tensile strength and elongation at break, they, respectively, grow by 47 and 15%, when the nanocomposite resin is compared with the neat resin. A very low volumetric shrinkage of 0.7% and a remarkable printing quality of objects obtained with this new photopolymer will enable the 3D printing of microrobots, bioengineering microdevices, and sensors. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48333. 相似文献
105.
Use of sourdough fermented wheat germ for enhancing the nutritional, texture and sensory characteristics of the white bread 总被引:3,自引:1,他引:3
Carlo Giuseppe Rizzello Luana Nionelli Rossana Coda Raffaella Di Cagno Marco Gobbetti 《European Food Research and Technology》2010,230(4):645-654
Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5, isolated from wheat germ and selected based on the kinetics of acidification, were used as starters for the manufacture
of sourdough fermented wheat germ. A bread containing sourdough fermented wheat germ as an ingredient (SFWGB) was compared
to breads made with (raw wheat germ bread, RWGB) or without (wheat flour bread, WFB) raw wheat germ. The higher concentration
of free amino acids mainly differentiated SFWGB from WFB and RWGB. The in vitro protein digestibility of WFB was the highest,
even if sourdough fermentation of wheat germ attenuated the difference. Phytase and antioxidant activities of SFWGB were highest.
The specific volume and cell-total areas were also the highest for SFWGB. As determined by texture profile analysis, the values
of hardness, resilience and fracturability of breads containing wheat germ were lower than those found in WFB. The crust lightness
showed a decrease from WFB to SFWGB. As determined by sensory analysis, SFWGB had mainly acid taste and flavour and resulted
more salty. Sourdough fermented wheat germ is an ingredient able to enhance nutritional, texture and sensory properties of
bread. 相似文献
106.
Gracin Trivio María Concepcin Serrano Raffaella Pagani María Teresa Portols 《大分子材料与工程》2005,290(10):953-960
Summary: A customized instrument has been developed as part of multidisciplinary research work relating to the development of a biodegradable vascular scaffold. This instrument aims to measure the mechanical properties of elastic and viscoelastic thin membranes with tissue engineering applications. Uniform and omni‐directional pressure is applied on the whole membrane which is uniformly clamped and submerged into a liquid medium. The mechanical testing described in this study is focused on the stress‐strain curves of polycaprolactone (PCL) films after different treatments. The influence of Dulbecco's modified Eagle's culture medium, L929 fibroblast culture, NaOH treatment and film thickness on the mechanical properties of PCL films was evaluated after different times. These studies show that the PCL degradation process is influenced by immersion in the culture medium, inducing an increment in the slope of the pressure‐dilation curve which is indicative of an increase in the polymer stiffness. On the other hand, long NaOH treatments make PCL films have more flexible behavior.
107.
Pansoo Kim Raffaella Pedone Marco Villanti Alessandro Vanelli‐Coralli Giovanni Emanuele Corazza Dae‐Ig Chang Deock‐Gil Oh 《International Journal of Satellite Communications and Networking》2009,27(1):35-52
This paper tackles the problem of frame synchronization design for the Digital Video Broadcasting standard via Satellite (DVB‐S2) system. In particular, the design of a novel frame detection scheme exhibiting robustness against large frequency errors is proposed. Post‐detection integration (PDI) is exploited to provide coarse frame alignment with limited complexity with respect to classical approximate maximum likelihood (ML) solutions. The novel scheme, denoted as differential generalized post‐detection integration, derives from a pragmatic adaptation of the well‐known generalized PDI scheme (IEEE Trans. Commun. 2007; 55 (11):2159–2171), which eliminates its inherent source of weakness in the presence of large frequency offsets, i.e. its non‐differential component given by non‐coherent PDI. The proposed approach manages to reduce the remarkable performance gap with respect to approximate ML techniques available in the literature (IEEE Trans. Commun. 2002; 50 (7):1062–1065), providing the designer with an interesting performance/complexity trade‐off. Performance is numerically evaluated in terms of receiver operating characteristics and mean acquisition time (MAT), handling the acquisition procedure according to a single‐dwell approach. Both threshold crossing and MAX criterion are contrasted to identify the best design solution. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
108.
Jane Cleland-Huang Raffaella Settimi Xuchang Zou Peter Solc 《Requirements Engineering》2007,12(2):103-120
This paper describes a technique for automating the detection and classification of non-functional requirements related to
properties such as security, performance, and usability. Early detection of non-functional requirements enables them to be
incorporated into the initial architectural design instead of being refactored in at a later date. The approach is used to
detect and classify stakeholders’ quality concerns across requirements specifications containing scattered and non-categorized
requirements, and also across freeform documents such as meeting minutes, interview notes, and memos. This paper first describes
the classification algorithm and then evaluates its effectiveness through reporting a series of experiments based on 30 requirements
specifications developed as term projects by MS students at DePaul University. A new and iterative approach is then introduced
for training or retraining a classifier to detect and classify non-functional requirements (NFR) in datasets dissimilar to
the initial training sets. This approach is evaluated against a large free-form requirements document obtained from Siemens
Logistics and Automotive Organization. Although to the NFR classifier is unable to detect all of the NFRs, it is useful for
supporting an analyst in the error-prone task of manually discovering NFRs, and furthermore can be used to quickly analyse
large and complex documents in order to search for NFRs. 相似文献
109.
Francesca Tosetti Massimo Alessio Alessandro Poggi Maria Raffaella Zocchi 《International journal of molecular sciences》2021,22(9)
Enzymes, once considered static molecular machines acting in defined spatial patterns and sites of action, move to different intra- and extracellular locations, changing their function. This topological regulation revealed a close cross-talk between proteases and signaling events involving post-translational modifications, membrane tyrosine kinase receptors and G-protein coupled receptors, motor proteins shuttling cargos in intracellular vesicles, and small-molecule messengers. Here, we highlight recent advances in our knowledge of regulation and function of A Disintegrin And Metalloproteinase (ADAM) endopeptidases at specific subcellular sites, or in multimolecular complexes, with a special focus on ADAM10, and tumor necrosis factor-α convertase (TACE/ADAM17), since these two enzymes belong to the same family, share selected substrates and bioactivity. We will discuss some examples of ADAM10 activity modulated by changing partners and subcellular compartmentalization, with the underlying hypothesis that restraining protease activity by spatial segregation is a complex and powerful regulatory tool. 相似文献
110.