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1.
Industrial and biotechnological applications of laccases: a review   总被引:21,自引:0,他引:21  
Laccases have received much attention from researchers in last decades due to their ability to oxidise both phenolic and non-phenolic lignin related compounds as well as highly recalcitrant environmental pollutants, which makes them very useful for their application to several biotechnological processes. Such applications include the detoxification of industrial effluents, mostly from the paper and pulp, textile and petrochemical industries, use as a tool for medical diagnostics and as a bioremediation agent to clean up herbicides, pesticides and certain explosives in soil. Laccases are also used as cleaning agents for certain water purification systems, as catalysts for the manufacture of anti-cancer drugs and even as ingredients in cosmetics. In addition, their capacity to remove xenobiotic substances and produce polymeric products makes them a useful tool for bioremediation purposes. This paper reviews the applications of laccases within different industrial fields as well as their potential extension to the nanobiotechnology area.  相似文献   

2.
In this study proteins extracted from prepupae of Hermetia illucens, also known as black soldier fly, are investigated as promising base for a new type of bioplastics for agricultural purposes. Design of experiments techniques are employed to perform a rational study on the effects of different combination of glycerol as plasticizer, citric acid as cross-linking agent and distilled water as solvent on the capability of proteins to form a free-standing film through casting technique, keeping as fixed the quantity of proteins. Glycerol shows interesting properties as plasticizer contributing to the formation of homogenous and free-standing film. Moreover, mechanical and thermal characterizations are performed to estimate the effect of increasing amounts of proteins on the final properties and thickness of the specimens. Proteins derived from H. illucens can be successfully employed as base for bioplastics to be employed for agricultural purposes.  相似文献   

3.
Web services are evolving and gaining wide acceptance as a standard for distributed computing. Organisations are starting to rely on them to conduct their core business, thereby enabling access to a huge amount of sensitive personal, medical and financial information that they hold, as well as information held on behalf of their customers, such as governments. Clearly, security for such web services is critical. Biometrics can play an important role in web services in a number of ways, providing improved levels of security and convenience for end-users. Emerging XML-based standards for carrying biometric information and exploiting cryptographic techniques may act as an enabler for biometrics.There has been considerable excitement in the world of information technology about web services. Indeed, they are seen as the next major revolution hitting the internet, enabling applications and organisations to interact with one another more directly and efficiently. However, security for web services is seen as a major challenge to be overcome before widespread deployment is possible. At the same time, biometric technologies continue to advance, with growing impetus behind the establishment of common standards for distributed biometric systems. This article explores web services and biometrics and examines the potential for the technologies to be of mutual benefit to each other.  相似文献   

4.
Centrifuges are often used in biological studies for 1 x g control samples in space flight microgravity experiments as well as in ground based research. Using centrifugation as a tool to generate an Earth like acceleration introduces unwanted inertial shear forces to the sample. Depending on the centrifuge and the geometry of the experiment hardware used these shear forces may contribute as much as 99% to the total force acting on the cells or tissues. The inertial shear force artifact should be dealt with for future experiment hardware development for Shuttle and the International Space Station (ISS) as well as for the interpretation of previous spaceflight and on-ground research data.  相似文献   

5.
A new digital computer program has been developed for the seriation of anthropological data. The program facilitates and refines procedures in the application of certain matrix-ordering approaches, such as the Brainerd-Robinson technique. The new program has special advantages for obtaining the best ordering of a case that is inherent in the data, together with special provisions for experimentation. Some of the innovations consist of working with the whole matrix pattern from start to finish, more exhaustive row-column comparisons, provision for specifying different ordering criteria, consistent utilization of a chosen criterion for matrix evaluation as well as for row-column placement, and a means of lessening the effect of input-order bias. The program is designed to produce a close approximation of an ideal model in order to place data collections as accurately as possible on a continuum of similarity for purposes such as chronological ordering and the expression of intercultural relationships.  相似文献   

6.
1. The volume-tonicity relations for human red cells exposed to a temperature of 48 degrees C. for 2 minutes remain the same as those for unheated human red cells. The heated systems show lysis in higher tonicities than the unheated systems do; this is probably largely due to fragmentation with its effect on the geometry of the situation, as suggested by Ham, Shen, Fleming and Castle. When the cells are heated to 48 degrees C. for longer times, the amount of fragmentation becomes considerable, but the volume-tonicity relation remains the same as before; the properties which are usually referred to as the osmotic properties of the red cell are accordingly not necessarily dependent on the integrity of the cell as a unit. 2. Heating to 52 degrees C. for 2 minutes profoundly modifies the volume-tonicity relation, very little swelling now occurring even in tonicities as low as 0.6. This is partly accounted for by the large K losses and K-Na exchanges which occur and which become greater as the tonicity is reduced and as the temperature is increased. Fragmentation and hemolysis also increase, the latter out of proportion to the expected effects of the former. Direct effects of heat on the cohesion of the red cell ultrastructure are probably involved.  相似文献   

7.
Management programmes often have to make decisions based on the analysis of the genetic properties and diversity of populations. Expected heterozygosity (or gene diversity) and population structure parameters are often used to make recommendations for conservation, such as avoidance of inbreeding or migration across subpopulations. Allelic diversity, however, can also provide complementary and useful information for conservation programmes, as it is highly sensitive to population bottlenecks, and is more related to long‐term selection response than heterozygosity. Here we present a completely revised and updated re‐implementation of the software metapop for the analysis of diversity in subdivided populations, as well as a tool for the management and dynamic estimation of optimal contributions in conservation programmes. This new update includes computation of allelic diversity for population analysis and management, as well as a simulation mode to forecast the consequences of taking different management strategies over time. Furthermore, the new implementation in C++ includes code optimization and improved memory usage, allowing for fast analysis of large data sets including single nucleotide polymorphism markers, as well as enhanced cross‐software and cross‐platform compatibility.  相似文献   

8.
The need for peroxidase purification is stressed as a requirement for comparative studies on isoenzyme structure as well as for detailed investigations on biosynthesis. A single cationic protein possessing the major peroxidase activity was isolated from the medium in which peanut cells had grown. The antibodies raised against this pure protein were employed as a probe to study the site of synthesis of peroxidase in the cell as well as the proportion of total synthesized protein which was peroxidase. Structural studies on the purified isoenzymes suggest the presence of three gene loci for peroxidase in cultured peanut cells. The results are discussed together with potential assays for induction of this enzyme and the relationship to cell development.  相似文献   

9.
10.
The application of artificial microbial consortia for biotechnological production processes is an emerging field in research as it offers great potential for the improvement of established as well as the development of novel processes. In this review, we summarize recent highlights in the usage of various microbial consortia for the production of, for example, platform chemicals, biofuels, or pharmaceutical compounds. It aims to demonstrate the great potential of co-cultures by employing different organisms and interaction mechanisms and exploiting their respective advantages. Bacteria and yeasts often offer a broad spectrum of possible products, fungi enable the utilization of complex lignocellulosic substrates via enzyme secretion and hydrolysis, and microalgae can feature their abilities to fixate CO2 through photosynthesis for other organisms as well as to form lipids as potential fuelstocks. However, the complexity of interactions between microbes require methods for observing population dynamics within the process and modern approaches such as modeling or automation for process development. After shortly discussing these interaction mechanisms, we aim to present a broad variety of successfully established co-culture processes to display the potential of artificial microbial consortia for the production of biotechnological products.  相似文献   

11.
To study influence of "low radiodoses" on their early effects, the method to monitor peculiarities for human biochemphysic pathologies caused by technogenic chronic doses divided by natural constant radiation background doses (relative radiation loads as their ratios, RRL) has been developed. High radiolabile coupled system of harmful catabolites of the initiated lipoperoxic cascade with essential radioprotectors (vitamins A and E as natural antioxidants) as pathogenic significant test-objects were monitored. For exposed children low radiation technogenic doses were high enough as RRL to disturb and to dysregulate both systems. For evaluation of individual radiosensitivity significances of age for children especially, as of the biochemical status for both systems are shown. The approach permits to investigate pathologies of studied systems as primary factors for mechanisms of related radiogenic known somatic health secondary consequences and to use it for some important practical applications.  相似文献   

12.
This paper uses original survey data of the Great East Japan earthquake disaster victims to examine their decision to apply for the temporary housing as well as the timing of application. We assess the effects of victims’ attachment to their locality as well as variation in victims’ information seeking behavior. We additionally consider various factors such as income, age, employment and family structure that are generally considered to affect the decision to choose temporary housing as victims’ solution for their displacement. Empirical results indicate that, ceteris paribus, as the degree of attachment increases, victims are more likely to apply for the temporary housing but attachment does not affect the timing of application. On the other hand, the victims who actively seek information and are able to collect higher quality information are less likely to apply for the temporary housing and if they do apply then they apply relatively later.  相似文献   

13.
The purpose of this study was to determine taste difference thresholds for monosodium glutamate (MSG) and sodium chloride (NaCl) in pigtail macaques (Macaca nemestrina) and spider monkeys (Ateles geoffroyi). Using a two-bottle preference test of brief duration, three animals of each species were presented with four different reference concentrations of 50, 100, 200, and 400 mM of a tastant and tested for their ability to discriminate these from lower concentrations of the same tastant. The just noticeable differences (JNDs), expressed as Weber ratios (DeltaI/I), were found to range from 0.1 to 0.5 for MSG and 0.2 to 0.45 for NaCl in the pigtail macaques, with a significant tendency for higher Weber ratios with higher reference concentrations. In the spider monkeys, JNDs ranged from 0.15 to 0.4 for MSG and 0.1 to 0.25 for NaCl, with Weber ratios staying fairly constant across the reference concentrations tested. Thus, the JNDs were found to be generally similar in both species and to be at least as low as those found in humans for MSG and NaCl, as well as those found in spider monkeys for sucrose. The results support the assumption that both pigtail macaques and spider monkeys may use differences in perceived intensity of MSG and NaCl as a criterion for food selection.  相似文献   

14.
Asveld L 《Bioethics》2008,22(5):245-257
Respect for autonomy is problematic in relation to public health programmes such as vaccination, as the success of such programmes depends on widespread compliance. European countries have different policies for dealing with objectors to vaccination programmes. In some countries compliance is compulsory, while in others objectors are exempted or allowed to enter the programme under specific conditions.
In this paper I argue that the objectors should not be treated as a homogenous group as is done in the above-mentioned policies. Objectors have different arguments for not participating in vaccination programmes. Considering the value of respect for autonomy, some but not all of these arguments need to be accommodated by authorities.
The concept of 'narrative autonomy' provides criteria to distinguish between tenable and untenable claims to the right to refuse vaccination. Narrative autonomy understands autonomy as essentially linked to identity, as this provides the moral framework with which we assess our first-order preferences.
The above-mentioned concept of autonomy is derived from the concept of narrative identity as described by Marya Schechtman. She suggests that the application of the Articulation Constraint and the Reality Constraint enables us to establish the validity of personal narratives. Additionally, form and content features of identity, as proposed by Anthony Laden, will be used as criteria to establish the compatibility of the defectors' arguments with shared scientific and political values. Such compatibility is essential to accommodate respect for autonomy in the context of public health.  相似文献   

15.
Three-dimensional cellular structures formed by MCF-7 human mammary carcinoma cells within collagen gels were isolated with collagenase and cultivated on plastic substratum to examine whether the cytoskeleton specific for cells forming cellular structures (S-type) changes to that specific for cells grown as monolayers (M-type). The cytoskeleton isolated as 0.05% Triton-insoluble fraction from the cellular structures after culture for 1 day on plastic was exclusively S-type. However, both types of cytoskeletons were observed in the cellular structures cultivated for 7 days on plastic as well as in the cells grown as monolayers for 2 days after dissociation of the cellular structures with trypsin. By use of an antibody raised against a 65-kD polypeptide that was specific for the M-type cytoskeleton, the presence of the polypeptide was found to be restricted to the cells grown out as monolayers from the edge of the cellular structures. In the cells grown for 2 days as monolayers, a mixture of cells both having and lacking the polypeptide was observed. After a 7-day culture of the dissociated cells as monolayers on plastic, however, most of the cells had M-type cytoskeletons. The present results show that the apparent change in the cytoskeleton of MCF-7 cells from S-type to M-type does not occur in cells involved in the three-dimensional cellular structures even in the absence of collagen gels, but that it occurs in cells which are grown as monolayers for at least 7 days on plastic substratum.  相似文献   

16.
Rat ear reattachment as an animal model   总被引:4,自引:0,他引:4  
The external ear of the rat is an excellent model for practicing microsurgical dissection and for the refinement of microvascular anastomoses, techniques that are crucial for microvascular en bloc tissue transfer and replantation. Preparation of the rat ear for replantation requires familiarity with the vascular anatomy and gentle tissue handling with atraumatic dissection of arterial and venous pedicles, steps similarly crucial in raising free flaps for microvascular transfer. The strategy of performing accurate reduction and stabilization of the tubal cartilage prior to vessel repairs, anastomosing the more deeply seated external carotid artery prior to the more superficial posterior facial vein, is as critical to rat ear replantation as for digital reattachment. In addition, the rat ear as compared to other animal models such as the rabbit ear or canine hindlimbs is much less expensive. Compared to the rat hindlimb model, rat ears are much easier to observe, which is a distinct advantage when used as a model for long-term study of replantation, revascularization, or transplantation.  相似文献   

17.
WHO Collaborating Centres (CCs) form part of an international collaborative network set up by WHO in support of its mandated programme at the country, intercountry, regional, interregional and global levels, as appropriate. As part of its mandate in the area of biologicals, WHO has broadened the scope of its work and has expanded the range of activities devoted to the establishment of international standards for vaccines. In line with global immunization goals, the need for standards for evaluation of quality, safety and efficacy of new vaccines, as well as those that have been in use for a long time, has significantly increased. Furthermore, complex issues related to new production methodologies, more sophisticated techniques for characterization and laboratory testing, and for nonclinical and clinical evaluation of vaccines have raised a number of regulatory challenges for WHO when requested to assist its Member States. In this context, CCs in the area of standardization of vaccines and biotherapeutics (excluding blood products) have provided technical assistance and have broadened the scope of their work over time. In the area of standardization and regulatory evaluation of vaccines, WHO currently has six CCs as well as one candidate centre for which the designation process has been initiated and a further three candidate centres with great potential. The purpose of the meeting held on 24–26 April 2012 was to improve understanding of WHO's priorities in setting standards, to facilitate their implementation, and to increase transparency of the roles and responsibilities of CCs. The meeting was also an excellent opportunity to explore possibilities for improving collaboration between WHO and CCs, as well as among CCs themselves by working as a CC network. All CCs expressed a wish for increased interaction, information-sharing, collaboration and other ways of working together that may lead to cross-fertilization between the CCs. Synergy was recognized as a significant mechanism for leveraging existing resources in responding to global public health challenges and in addressing WHO's priorities. Agreement was reached for operating as a network of CCs.  相似文献   

18.
A nonadecanucleotide has been used both as a site specific mutagen to introduce a T leads to A transversion mutation in the human beta-globin gene cloned in pBR322 as well as a probe to screen transformed colonies for the desired mutant. The specificity of the oligonucleotide as a mutagen and as a hybridization probe provide a general method for producing site specific mutations in DNA cloned in plasmid vectors such as pBR322.  相似文献   

19.
绿色屋顶项目通过释放屋顶空间的利用潜能,满足人们应对气候变化的挑战、在越加拥挤的城市中的公共场所进行休闲娱乐的需求,以及需要更加环保城市的同时,建造道路、停车场及其他类型建筑的需求。屋顶绿化是一种独特的解决途径,能够为人们带来众多益处,因此它也被认为是城市开发中最具有可持续发展、最能适应气候变化的手法之一。它是工业化城市向环保类型城市转变的关键。为推进这一进程,我们必须关注屋顶绿化的重要性,并将其纳入未来城市规划政策之中。  相似文献   

20.
The terms biosphere, ecosphere, and Gaia are used as names for the global ecosystem. However, each has more than one meaning. Biosphere can mean the totality of living things residing on the Earth, the space occupied by living things, or life and life-support systems (atmosphere, hydrosphere, lithosphere, and pedosphere). Ecosphere is used as a synonym of biosphere and as a term for zones in the universe where life as we know it should be sustainable. Gaia is similar to biosphere (in the sense of life and life-support systems) and ecosphere (in the sense of biosphere as life and life-support systems), but, in its most extreme form, refers to the entire planet as a living entity. A case is made for avoiding the term Gaia (at least as a name for the planetary ecosystem), restricting biosphere to the totality of living things, and adopting the ecosphere as the most apt name for the global ecosystem.  相似文献   

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