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101.
102.
Proteases occupy the most relevant position among industrial enzymes. Plant proteases have been used in medicine, detergent manufacturing, and food science for many years, but their production is diminishing in favor of those of microbial origin because lower production costs. Papain, bromelain, and ficin are the most frequently employed plant proteases, although new proteases with new and more appealing physicochemical properties for industry are still emerging. DNA technology and genetic engineering shall play, without a doubt, an important role for the production of these proteases at the industrial level. The present review focuses on the applications of traditional plant proteases as well as new proteases discovered during the last 20 years, some of which have already been genetically engineered either to increase production or to strengthen some of their physicochemical properties. The review also refers to the protease classification, action pattern, and main characteristics. 相似文献
103.
This paper presents a mechanics study of the variations with position and time of stresses within the dermis and epidermis of a human fingertip when it is loaded and slid over textured surfaces. Its purpose is to examine how fingerprints interact with surface texture to cause stress variations in tune with the sensitivities of Meissner and Pacinian corpuscles through which humans in part interpret tactile sensations. A two-dimensional multilayer elastic finite element model of a fingertip has been created for this purpose. Results show that fingertip’s epidermal ridges have little effect on stress distribution within the fingertip in static loading but significantly increase stress oscillations during sliding over a textured surface. Oscillation frequencies from the sliding simulations are in ranges that should stimulate a fingertip’s Meissner and Pacinian corpuscle nerve endings. 相似文献
104.
Syadaruddin Syachrani Hyung Seok Jeong Vajra Rai Myung Jin Chae Tom Iseley 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2010,25(6):681-688
Proper functioning of culverts is not only critical to protecting the transportation system from flooding but also critical to maintaining the expected service life of the overall transportation system. During the service life of culverts, they deteriorate due to many reasons such as corrosion caused by road salt, blockage by debris and sediment, poor construction techniques, etc. Trenchless technologies have been used by several State Departments of Transportation (DOTs) to rehabilitate deteriorated drainage structures without disrupting the traffic and within a relatively short span of time. These technologies provide many benefits in terms of cost, time, quality, and expected service life. However, the safety aspects of these techniques have not been discussed and documented in detail probably due to the complexity and the lack of safety standards and specifications directly associated with the techniques. This paper discusses the application of a risk assessment framework to assess potential safety issues of currently available trenchless technologies for culvert rehabilitation. The findings of the study will provide additional information to improve the decision making process in selecting and planning culvert rehabilitation projects. 相似文献
105.
Felicity S Jackson Tom N Barry Carlos Lascano Brian Palmer 《Journal of the science of food and agriculture》1996,71(1):103-110
The extractable, protein-bound and fibre-bound condensed tannin (CT) concentrations in the leaves of tropical legumes grown in both Colombia and Northern Australia were determined by the butanol–HCl method, whilst extractable CT was also determined by the vanillin–HCl method. With the exception of Senna siamea all species contained CT. The very high CT concentration found in many plants growing in Colombia may have been partly due to soil fertility being much lower at the Colombian than the Northern Australian site. Acacia boliviana , Arachis pintoi , Centrosema latidens , Senna velutina and Gliricidia sepium contained <55 g total CT kg−1 DM, which suggests that they could comprise a reasonable proportion of ruminant diets. All other species grown in South America contained 100–240 g CT kg−1 DM, which suggests that they should only be fed in small amounts as supplements to dilute the CT concentration. Leucaena species and Calliandra calothyrsus grown in Northern Australia contained intermediate concentrations of total CT (60–90 g kg−1 DM). Most species contained 70–95% of total CT as extractable CT, with the exception of Flemingia macrophylla , where 60% was extractable and 40% bound, and Gliricidia sepium , where almost all the CT was bound to protein. Values for Flemingia macrophylla differed between accessions. Extractable CT determined with vanillin–HCl was generally higher than extractable CT determined with butanol–HCl. Three accessions showed negligible (<1 g kg−1 DM) extractable CT with butanol–HCl but 10–12 g extractable CT kg−1 DM with vanillin–HCl. Two accessions showed undetectable levels of extractable CT but substantial levels of protein-bound CT, illustrating the importance of using a bound CT method for identifying forages containing CT. Relative to freeze drying, oven drying of Leucaena species reduced the concentration of extractable CT and increased concentrations of bound CT. The significance of the results for the nutrition of ruminant livestock are discussed, including the possible roles of protein-bound and fibre-bound CT. 相似文献
106.
Neumann Sebastian Asad Amjad Kasper Tom Schwarze Rüdiger 《Metallurgical and Materials Transactions B》2019,50(5):2334-2342
Metallurgical and Materials Transactions B - In the paper, two different cleaning strategies for nonmetallic inclusions in steel melts, active filtration and reactive cleaning, are examined in a... 相似文献
107.
Between ‘Platial’ Imaginations and Spatial Rationalities: Navigating Justice and Law in the Low Countries 总被引:1,自引:0,他引:1
Tom Mels 《Landscape Research》2013,38(3):321-335
During the past two decades, landscape has frequently been conceptualized as a distancing way of seeing space. This conceptualization is normally traced back to the rise of capitalism and various modes of artistic representation, notably in the early modern Netherlands or the northern Low Countries. Yet recent scholarly interventions have asserted that landscape in the Low Countries and elsewhere in Europe was more than a distant scenery or an artistic mode of representation. Landscape also animated practices and ideologies of political representation, platial justice and custom. The platial notion of landscape and related concepts in the northern Low Countries around 1600 is focused upon, bringing out the intimate relationships between land, water and diverging ideals and practices of justice. It is argued that artistic landscape representation provided ways to reflect upon spatio-political developments in the Netherlands. Finally, there is a brief consideration of how these theoretical and historical issues resonate with modern thinking about landscape in physical planning. 相似文献
108.
Araceli Diez-Fraile Joke De Ceulaer Charlotte Derpoorter Christophe Spaas Tom De Backer Philippe Lamoral Johan Abeloos Tim Lammens 《International journal of molecular sciences》2022,23(5)
The 5-year relative survival for patients with head and neck cancer, the seventh most common form of cancer worldwide, was reported as 67% in developed countries in the second decade of the new millennium. Although surgery, radiotherapy, chemotherapy, or combined treatment often elicits an initial satisfactory response, relapses are frequently observed within two years. Current surveillance methods, including clinical exams and imaging evaluations, have not unambiguously demonstrated a survival benefit, most probably due to a lack of sensitivity in detecting very early recurrence. Recently, liquid biopsy monitoring of the molecular fingerprint of head and neck squamous cell carcinoma has been proposed and investigated as a strategy for longitudinal patient care. These innovative methods offer rapid, safe, and highly informative genetic analysis that can identify small tumors not yet visible by advanced imaging techniques, thus potentially shortening the time to treatment and improving survival outcomes. In this review, we provide insights into the available evidence that the molecular tumor fingerprint can be used in the surveillance of head and neck squamous cell carcinoma. Challenges to overcome, prior to clinical implementation, are also discussed. 相似文献
109.
S. Voss R. SteinbrückM. Kautz E. SchießwohlM. Arendt J. Tom FeldeJ. Volkert D. Trimis 《International Journal of Hydrogen Energy》2011,36(5):3697-3703
The advance of efficient hydrogen-air combustion systems has increasingly become of interest in the framework of the development of fuel cell systems, especially for the automotive sector. Therefore, compact modulating systems are required, with the additional demand of low emissions, to be integrated in a fuel cell system. A modulating combustion system based on combustion within inert porous media and an integrated heat exchanger has been developed and investigated. The system is able to handle premixed combustion of lean H2/air mixtures at a surface load range of 1075 kW/m2-2150 kW/m2, and a global equivalence ratio of ?=0.5. The special hydrogen-air mixing concept eliminates the risk of flame flashback and enables operation with very low NOx emissions. 相似文献
110.
Alfonso P. Ramallo-González Matthew Brown Elizabeth Gabe-Thomas Tom Lovett David A. Coley 《Journal of Building Performance Simulation》2018,11(1):65-83
The reduction of energy use in buildings is a major component of greenhouse gas mitigation policy and requires knowledge of the fabric and the occupant behaviour. Hence there has been a longstanding desire to use automatic means to identify these. Smart metres and the internet-of-things have the potential to do this. This paper describes a study where the ability of inverse modelling to identify building parameters is evaluated for 6 monitored real and 1000 simulated buildings. It was found that low-order models provide good estimates of heat transfer coefficients and internal temperatures if heating, electricity use and CO2 concentration are measured during the winter period. This implies that the method could be used with a small number of cheap sensors and enable the accurate assessment of buildings’ thermal properties, and therefore the impact of any suggested retrofit. This has the potential to be transformative for the energy efficiency industry. 相似文献