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111.
De novo synthesis and mitochondrial elongation of fatty acids have been demonstrated in subcellular fractions from hog and human
aorta. Microsomal fatty acid elongation has been shown in hog aorta. The activity catalyzing the formation of fatty acids
from acetyl and malonyl CoA was associated with a high molecular weight complex in the 6×106g×min supernatant fraction. The principal product was palmitic acid. Some myristic and stearic acids were also formed. One
elongation system was associated with protein which sedimented between 4500 g×min and 150,000 g×min. It used acetyl CoA but
not malonyl CoA, and NADH was the preferred reducing agent. Radioactivity from acetyl CoA was incorporated into many fatty
acids. In hog aorta a second elongation system was found associated with protein which sedimented at 6×106 g×min. It used malonyl CoA preferentially as substrate and either NADH or NADPH as reducing agent. 相似文献
112.
Andro Mondala Rafael Hernandez William Holmes Todd French Linda McFarland Darrell Sparks Monica Haque 《American Institute of Chemical Engineers》2013,59(11):4036-4044
The co‐fermentation of glucose and xylose by activated sludge microorganisms for the production of microbial oils for use as biodiesel feedstock was investigated. Various carbon sources at initial concentration of 60 g/L and C:N ratio 70:1 were investigated: xylose, glucose, and 2:1 and 1:2 (by mass) glucose/xylose mixtures. Oil accumulation ranged between 12 to 22% CDW, the highest of which was obtained when xylose was the sole substrate used. Kinetic modeling of the fermentation data showed that specific growth and oil accumulation rates were similar in all substrate types and the lipid coefficient ranged from 0.02 to 0.06 g/g of sugar consumed. The fatty acid methyl ester yield and composition of the lipids showed their suitability for conversion to biodiesel. Based on the results, lignocellulose sugars could be used as fermentation substrates by activated sludge microorganisms for enhancing the oil content of sewage sludge for its use as a sustainable biofuel feedstock source. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4036–4044, 2013 相似文献
113.
Alessandro Marchioni Roberto Tonelli Alessandro Andreani Gaia Francesca Cappiello Matteo Fermi Fabiana Trentacosti Ivana Castaniere Riccardo Fantini Luca Tabbì Dario Andrisani Filippo Gozzi Giulia Bruzzi Linda Manicardi Antonio Moretti Serena Baroncini Anna Valeria Samarelli Massimo Pinelli Giorgio De Santis Alessandro Stefani Daniele Marchioni Francesco Mattioli Enrico Clini 《International journal of molecular sciences》2022,23(5)
Laryngotracheal stenosis (LTS) is a complex and heterogeneous disease whose pathogenesis remains unclear. LTS is considered to be the result of aberrant wound-healing process that leads to fibrotic scarring, originating from different aetiology. Although iatrogenic aetiology is the main cause of subglottic or tracheal stenosis, also autoimmune and infectious diseases may be involved in causing LTS. Furthermore, fibrotic obstruction in the anatomic region under the glottis can also be diagnosed without apparent aetiology after a comprehensive workup; in this case, the pathological process is called idiopathic subglottic stenosis (iSGS). So far, the laryngotracheal scar resulting from airway injury due to different diseases was considered as inert tissue requiring surgical removal to restore airway patency. However, this assumption has recently been revised by regarding the tracheal scarring process as a fibroinflammatory event due to immunological alteration, similar to other fibrotic diseases. Recent acquisitions suggest that different factors, such as growth factors, cytokines, altered fibroblast function and genetic susceptibility, can all interact in a complex way leading to aberrant and fibrotic wound healing after an insult that acts as a trigger. However, also physiological derangement due to LTS could play a role in promoting dysregulated response to laryngo-tracheal mucosal injury, through biomechanical stress and mechanotransduction activation. The aim of this narrative review is to present the state-of-the-art knowledge regarding molecular mechanisms, as well as mechanical and physio-pathological features behind LTS. 相似文献
114.
115.
As our elderly population increases in proportion with respect to the rest of society, age-related driving impairments are increasing in importance as a public health concern. In this context, health professionals play an important role in identifying impaired drivers. This situation is complicated for two reasons: discussion of driving cessation is a sensitive topic for both health professionals and the elderly, and physicians have limited familiarity with the current American Medical Association (AMA) screening guidelines or mandated reporting laws. 相似文献
116.
Morphologically dependent alternating‐current and direct‐current breakdown strength in silica–polypropylene nanocomposites
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Timothy Krentz Mohammad M. Khani Michael Bell Brian C. Benicewicz J. Keith Nelson Su Zhao Henrik Hillborg Linda S. Schadler 《应用聚合物科学杂志》2017,134(1)
In this article, we report the synthesis of a new bimodal surface ligand morphology on silica nanoparticles. Combining grafting‐to and grafting‐from approaches, in this study, we demonstrated the efficacy of anthracene surface modification for improving the dielectric breakdown strength (DBS) under alternating‐current and direct‐current conditions and that of a matrix‐compatible polymer brush for controlling the nanofiller (NF) dispersion. Ligand‐modified spherical colloidal SiO2 nanoparticles (~14 nm in diameter) were mixed into polypropylene, and the resulting dispersion was improved over the unmodified particles, as shown with transmission electron microscopy. The results suggest that the electronic structure of the anthracene‐modified particle surface was critical to the improvement in DBS. In addition, the DBS of the composite was shown to depend on the dispersion state of the filler and the mode of stress; this indicated that the individually dispersed nanoparticles were not necessarily the optimal morphology for all stress conditions. Additionally, the precise nature of the matrix‐compatible brush was less important than the NF dispersion it produced. The bimodal grafted architectural design has provided a promising solution for the control of the dispersion and surface properties, especially for high‐molecular‐weight polymer matrices. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44347. 相似文献
117.
Considerable interest has been shown in the ability of caloric restriction (CR) to improve multiple parameters of health and to extend lifespan. CR is the reduction of caloric intake - typically by 20 - 40% of ad libitum consumption - while maintaining adequate nutrient intake. Several alternatives to CR exist. CR combined with exercise (CE) consists of both decreased caloric intake and increased caloric expenditure. Alternate-day fasting (ADF) consists of two interchanging days; one day, subjects may consume food ad libitum (sometimes equaling twice the normal intake); on the other day, food is reduced or withheld altogether. Dietary restriction (DR) - restriction of one or more components of intake (typically macronutrients) with minimal to no reduction in total caloric intake - is another alternative to CR. Many religions incorporate one or more forms of food restriction. The following religious fasting periods are featured in this review: 1) Islamic Ramadan; 2) the three principal fasting periods of Greek Orthodox Christianity (Nativity, Lent, and the Assumption); and 3) the Biblical-based Daniel Fast. This review provides a summary of the current state of knowledge related to CR and DR. A specific section is provided that illustrates related work pertaining to religious forms of food restriction. Where available, studies involving both humans and animals are presented. The review includes suggestions for future research pertaining to the topics of discussion. 相似文献
118.
Juan Gabriel Brida Marta Disegna Linda Osti 《Expert systems with applications》2012,39(13):11349-11356
Considering the importance of market segmentation as a marketing tool to determine promotional policies, this paper aims to contribute to the tourism literature using the two-level approach proposed by Vesanto and Alhoniemi (2000) as an alternative and effective method to conduct cluster analyses.For this purpose, an empirical study was conducted interviewing tourists who visited three different Christmas Markets in Northern Italy. The two-level approach is based on two clustering techniques used in sequence: a Self-Organizing Map (SOM) followed by a clustering algorithm. The Silhouette index (Rousseeuw, 1987) is used as a guideline during the second level in the selection process of both the best clustering techniques (between hierarchical and non-hierarchical) and the best partition.The analysis identified three cluster segments and this paper demonstrates the suitability of the clustering method adopted. In the discussion of the results, marketing and managerial implications are also highlighted. 相似文献
119.
Twambo Hachibamba Linda Dykes Joseph Awika Amanda Minnaar Kwaku G. Duodu 《International Journal of Food Science & Technology》2013,48(12):2638-2649
Consumption of diets rich in phenolic compounds has been associated with reduced risk of chronic diseases. The effect of cooking and simulated gastrointestinal digestion on phenolic compounds and antioxidant properties of two cowpea (Vigna unguiculata) types was determined. Phenolic acids, flavan‐3‐ols and flavonols were the main groups of phenolic compounds identified. Cooking and simulated enzyme digestion of the cooked cowpea samples rendered some phenolics less extractable (possibly by promoting binding with other food components) or more extractable (possibly by release of bound forms). Total phenolic contents and radical scavenging properties of the cowpeas were reduced upon cooking, but increased upon simulated enzyme digestion. Cowpea extracts inhibited human LDL oxidation at a concentration of 2 mg mL?1 possibly due to their phenolic content. Phenolic compounds in cowpea can potentially protect against cardiovascular diseases for which LDL oxidation is a risk factor. 相似文献
120.
Bond Kenneth; Ospina Maria B.; Hooton Nicola; Bialy Liza; Dryden Donna M.; Buscemi Nina; Shannahoff-Khalsa David; Dusek Jeffrey; Carlson Linda E. 《Canadian Metallurgical Quarterly》2009,1(2):129
The authors used a 5-round Delphi study with a panel of 7 experts in meditation research to achieve agreement on a set of criteria for a working definition of “meditation” for use in a comprehensive systematic review of the therapeutic use of meditation. Participants agreed that essential to a meditation practice is its use of (a) a defined technique, (b) logic relaxation, and (c) a self-induced state. Participants also agreed that a meditation practice may (d) involve a state of psychophysical relaxation somewhere in the process; (e) use a self-focus skill or anchor; (f) involve an altered state/mode of consciousness, mystic experience, enlightenment or suspension of logical thought processes; (g) be embedded in a religious/spiritual/philosophical context; or (h) involve an experience of mental silence. The results of this study provide insight into the challenges faced by researchers who want to demarcate meditative practices from nonmeditative practices, and they describe an approach to this problem that may prove useful for researchers trying to operationalize meditation in the context of comparative research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献