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1.
Denise Meyerson 《Bioethics》2015,29(5):342-352
Demands for access to experimental therapies are frequently framed in the language of rights. This article examines the justifiability of such demands in the specific context of surgical innovations, these being promising but non‐validated and potentially risky departures from standard surgical practices. I argue that there is a right to access innovative surgery, drawing analogies with other generally accepted rights in medicine, such as the right not to be forcibly treated, to buy contraceptives, and to choose to have an abortion, including a post‐viability abortion where the mother's life or health is threatened by the pregnancy. I argue that we accept these rights because we believe that people are entitled to try to preserve their lives and health and to make choices of an important and intensely personal kind, and I suggest that a person's choice of medical treatment should be seen in the same light. However, since few rights are absolute, I also consider the circumstances in which it may be justifiable to limit the right to access innovative surgery. In discussing this question, I apply the human rights standard of proportionality, comparing the importance of the reasons for limiting the right with the severity of the invasion on liberty.  相似文献   

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Somatic embryogenesis was achieved in callus cultures dervied from 40-day-old semimature zygotic embryos ofDalbergia sissoo on semi-solid Murashige and Skoog (MS) salts and vitamins supplemented with 0.46–1.16 M kinetin, 6.78–9.04 M 2,4-dichlorophenoxy acetic acid (2,4-D) and 30 g/1 sucrose. Somatic embryos proliferated rapidly by secondary somatic embryogenesis after transfer to half-strength basal MS medium supplemented with 0.46-1.16 M kinetin and 6.78–9.04 M 2,4-D with 2% (w/v) sucrose. The light-green somatic embryos germinated on half-strength MS salts and vitamins supplemented with 0.5 mg/1 abscisic acid and 2% (w/v) sucrose. The developmental stages of somatic embryogenesis were studied by light and scanning electron microscopy.Abbreviations ABA Abscisic acid - BA 6-benzyladenine - Kn kinetin - 2,4-D 2,4-dichlorophenoxyacetic acid - NAA 1-naphthaleneacetic acid - MS Murashige and Skoog (1962) basal medium  相似文献   

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This article reports findings from a study investigating undergraduate biological sciences students' use of technology and computer devices for learning and the effect of providing students with a tablet device. A controlled study was conducted to collect quantitative and qualitative data on the impact of a tablet device on students' use of devices and technology for learning. Overall, we found that students made extensive use of the tablet device for learning, using it in preference to laptop computers to retrieve information, record lectures, and access learning resources. In line with other studies, we found that undergraduate students only use familiar Web 2.0 technologies and that the tablet device did not alter this behavior for the majority of tools. We conclude that undergraduate science students can make extensive use of a tablet device to enhance their learning opportunities without institutions changing their teaching methods or computer systems, but that institutional intervention may be needed to drive changes in student behavior toward the use of novel Web 2.0 technologies.  相似文献   

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The standard approach in a biological two-player game is toassume both players choose their actions independently of oneanother, having no information about their opponent's action(simultaneous game). However, this approach is not realisticin some circumstances. In many cases, one player chooses hisaction first and then the second player chooses her action withinformation about his action (Stackelberg game). We comparethese two games, which can be mathematically analyzed into twotypes, depending on the direction of the best response function(BRF) at the evolutionarily stable strategy in the simultaneousgame (ESSsim). We subcategorize each type of game into two cases,depending on the change in payoff to one player, when both playersare at the ESSsim, and the other player increases his action.Our results show that in cases where the BRF is decreasing atthe ESSsim, the first player in the Stackelberg game receivesthe highest payoff, followed by both players in the simultaneousgame, followed by the second player in the Stackelberg game.In these cases, it is best to be the first Stackelberg player.In cases where the BRF is increasing at the ESSsim, both Stackelbergplayers receive a higher payoff than players in a simultaneousgame. In these cases, it is better for both players to playa Stackelberg game rather than a simultaneous game. However,in some cases the first Stackelberg player receives a higherpayoff than the second Stackelberg player, and in some casesthe opposite is true.  相似文献   

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C Dietrich  J Hart  D Raila  U Ravaioli  N Sobh  O Sobh  C Taylor 《ZooKeys》2012,(209):165-181
InvertNet, one of the three Thematic Collection Networks (TCNs) funded in the first round of the U.S. National Science Foundation's Advancing Digitization of Biological Collections (ADBC) program, is tasked with providing digital access to ~60 million specimens housed in 22 arthropod (primarily insect) collections at institutions distributed throughout the upper midwestern USA. The traditional workflow for insect collection digitization involves manually keying information from specimen labels into a database and attaching a unique identifier label to each specimen. This remains the dominant paradigm, despite some recent attempts to automate various steps in the process using more advanced technologies. InvertNet aims to develop improved semi-automated, high-throughput workflows for digitizing and providing access to invertebrate collections that balance the need for speed and cost-effectiveness with long-term preservation of specimens and accuracy of data capture. The proposed workflows build on recent methods for digitizing and providing access to high-quality images of multiple specimens (e.g., entire drawers of pinned insects) simultaneously. Limitations of previous approaches are discussed and possible solutions are proposed that incorporate advanced imaging and 3-D reconstruction technologies. InvertNet couples efficient digitization workflows with a highly robust network infrastructure capable of managing massive amounts of image data and related metadata and delivering high-quality images, including interactive 3-D reconstructions in real time via the Internet.  相似文献   

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A nontraditional approach to construction of metabolic charts is proposed. It is based on the discovery of symmetry in the structure of the network of metabolic reactions. So if compounds and reactions are located on the metabolic chart according to their chemical features, the chart structure will acquire a periodic pattern. The charts thus created have a natural two-dimensional coordinate system of the metabolic network. Points on the X-axis correspond to number of carbon atoms in the carbon skeleton of compounds in columns and points on the Y-axis correspond to number of -COOH groups in compounds filing in series of rows on the charts. As a result this coordinate system sections the field of the charts into rectangular blocks each of which containing compounds with the same numbers of carbon atoms and the same numbers of -COOH groups. The latter substantially improves the charts and makes them a more valid source of metabolic data possessing heuristic properties. The periodicity of the metabolic network structure enables us easily to remember information about biochemical reactions and their products. The charts can also be used as a universal key for any biological database information that is systematically connected with the metabolic information. The charts can be important for medicine and pharmacology because they can help to understand the metabolic processes involved in decomposition of a particular drug or to find the chain of reactions blocked or initiated by administering this drug into a living organism.Translated from Biokhimiya, Vol. 69, No. 12, 2004, pp. 1691–1699.Original Russian Text Copyright © 2004 by Malygin.  相似文献   

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Bodvin  Torjan  Indergaard  Mentz  Norgaard  Erik  Jensen  Arne  Skaar  Arne 《Hydrobiologia》1996,335(1):83-86
A method has been developed for the determination of H2S and FeS in sediments. FeS is converted into H2S which is flushed from the samples directly into an excess of chlorine bleach, NaC1O or KClO with some Zn2+ added. Either the excess can be titrated back potentiometrically with As2O3, or the sulphate formed can be measured colorimetrically. The precision is primarily controlled by the homogeneity of the sediment suspensions and can be better than 99%.  相似文献   

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Background, aim, and scope

The term “information module” has been initially introduced by ISO 14025 (ISO 14025 2006) which specifies Type III environmental declarations. It comprises a set of predetermined parameters (PDPs) assigned to a process. Such a process can be part of a product system, i.e., a unit process or a combination of unit processes as, e.g., the production processes of a company. Independent information modules (IIMs) of processes within a system are modeled in a way that the predetermined parameters of the information modules related to these processes are identical and sufficiently independent so they can be added up to the predetermined parameters of such a system, typically after multiplication with specific factors based on the reference flow of the system.

Materials and methods

This paper shows how IIMs can be used as powerful approach in life cycle management and how operations, goods, and services of a company can be modeled efficiently with the help of IIMs. To define environmental objectives of their operations, organizations typically assess their foreground processes but do not apply system expansion for each of the foreground processes to include background processes. With the help of IIMs, background processes can be easily included, and the PDPs, therefore, also include both direct and indirect elementary flows, i.e., emissions and resources. In a “plant ecobalance” the PDPs of the different (foreground and background) processes of an organization can be determined and added up. This provides each process owner with important information about the environmental aspects which he or she can control and shows options for setting and implementing environmental objectives. For specific purposes, the number of PDPs can be restricted or even limited to one parameter, e.g., the carbon footprint. This paper illustrates the method with one example of the aluminum industry (carbon footprint of an automotive bumper beam) and shows how PDPs of product systems can be built up from IIMs which represent the different stages of a life cycle; how such results can show the influence of these stages in a transparent way, as required as a part of the life cycle interpretation phase.

Results and discussion

Life cycle assessments (LCAs) based on IIMs follow the principles and requirements of ISO 14040 (2006) and ISO 14044 (2006), as applicable. However, as a specific approach of life cycle management, they can obtain the required information with less effort than “conventional” LCAs where, following the guidance of ISO 14044, indicator results are calculated after the inventory data have been aggregated for the whole product system. Future efforts in ISO standardization should strengthen the role of LCA as a tool of environmental management.
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The industrial sector is becoming increasingly interested in eliminating potential pollution at source and reducing energy use. Biotechnology provides cheaper, cleaner alternatives to a wide range of traditional processes--but its adoption has been slower than expected. If industry is to become truly compatible with the environment, companies and the public will have to be convinced of the ecological and economic value of clean technology.  相似文献   

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Extensive enthusiasm surrounds the potential for human DNA information to sustain and enhance the pharmaceutical industry's profitability. Nevertheless, persons whose health makes their DNA of commercial interest are routinely expected simply to give their DNA and the information in it to pharmaceutical or genomics companies or their academic intermediaries, voluntarily and without compensation. This state of affairs is increasingly recognized as paradoxical, but it is favored by conventional bioethical opinion. Given that most DNA information is now collected for commercial purposes and is worth considerably more than is generally imagined, bioethical objections to compensation of individuals for their DNA information are inappropriate. This paper suggests approaches by which individuals and representative governments and patient interest groups can negotiate compensation. Appreciable attitudinal change is required if those individuals personally involved are to be included fairly in the commercialization of human DNA information. Ultimately, however, such change is necessary if commercial genetic research is to respect human dignity and human rights.  相似文献   

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TRAIL, a putative anticancer cytokine, induces extrinsic cell death by activating the caspase cascade directly (Type I cells) via the death-inducing signaling complex (DISC) or indirectly (Type II cells) by caspase-8 cleavage of Bid and activation of the mitochondrial cell death pathway. Cancer cells are characterized by their dependence on aerobic glycolysis, which, although inefficient in terms of ATP production, facilitates tumor metabolism. Our studies show that TRAIL-induced cell death is significantly affected by the metabolic status of the cell. Inhibiting glycolysis with 2-deoxyglucose potentiates TRAIL-induced cell death, whereas glucose deprivation can paradoxically inhibit apoptosis. These conflicting responses to glycolysis inhibition are modulated by the balance between the Akt and AMPK pathways and their subsequent downstream regulation of mTORC1. This results in marked changes in protein translation, in which the equilibrium between anti- and pro-apoptotic Bcl-2 family member proteins is decided by their individual degradation rates. This regulates the mitochondrial cell death pathway and alters its sensitivity not only to TRAIL, but to ABT-737, a Bcl-2 inhibitor. Taken together, our studies show that the sensitivity of cancer cells to apoptosis can be modulated by targeting their unique metabolism in order to enhance sensitivity to apoptotic agents.  相似文献   

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Summary The two principal mycobacterial diseases — tuberculosis and leprosy — remain major causes of human suffering in many parts of the world. The struggle against these diseases has been hampered by the inadequacy of methods for their diagnosis, prevention and therapy. Improvements in diagnostic methods, especially for tuberculosis, are required as existing bacteriological techniques are time consuming and insensitive, but immunological tests suffer from a lack of specificity and a failure to distinguish active disease from past sensitization. Tests are required that will either detect the presence of mycobacterial antigens or the occurrence of immune reactions specific to active infection. Prophylaxis by BCG vaccine is never complete and in some regions appears virtually ineffective. In order to determine the reason for this variation, to produce better vaccines, and to use BCG more effectively, a deeper understanding of the immune reactions in mycobacterial disease is required. In particular, the bacterial determinants of virulence and protection and the mode of action of BCG require detailed study. The therapy of tuberculosis and, to a lesser extent, leprosy has undergone an extensive transformation since the introduction of rifampicin. Nevertheless the cost of modern short course regimens for tuberculosis limit their application. Even shorter regimens, made possible by more potent bactericidal drugs or by agents that stimulate the host's defences are thus required. Recent advances in biotechnology could therefore lead to significant advances in the control of these diseases but only if they are integrated into local, self-reliant public health initiatives.
Enfermedades producidas por microbacterias. Un desafío a la biotecnologia
Resumen La dos principales enfermedades producidas por micobacterias — tuberculosis y lepra —persisten como las causas más importantes del sufrimiento humano en muchas partes del mundo. La lucha contra estas enfermedades se ha visto dificultada por lo inadecuado de los métodos para su diagnosis, prevención y terapia. Es necesaria una mejora de los métodos de diagnosis, especialmente en el caso de la tuberculosis, ya que las técnicas bacteriológicas existentes son poco sensibles y consumen mucho tiempo y los tests inmunológicos son inespecíficos y no permiten distinguir entre la enfermedad activa y la sensibilidad adquirida. Se necesitan tests capaces de detectar la presencia de antígenos microbacterianos o la existencia de reacciones de inmunización específicas de la infección activa. La profilaxis con la vacuna BCG no es nunca completa y en algunas regiones es virtualmente enefectiva. Con objeto de determinar las razones de esta variación, de producir mejores vacunas y de usar la BCG de forma más eficiente, se necesita entender con más profundidad las reacciones de inmunización en las enfermedades por micobacterias. En particular los determinantes bacterianos de la virulencia y de la protección y la forma de actuar de la BCG precisan de un estudio detallado. La terapia de la tuberculosis y en menor grado la de la lepra, han sufrido una extensa transformación desde la introducción de la rifampicina. Sin embargo, el costo de los modernos tratamientos a corto plazo de la tuberculosis limítan su aplicación. Se requieren tratamientos aún más cortos basados en el desarrollo de drogas bactericidas más potentes o de agentes que estimulen las defensas del enfermo. Los recientes avances en biotecnología podrían por tanto conducir a avances importantes en el control de estas enfermedades pero solamente si se integran en iniciativas médicas públicas consistentes.

Les maladies à mycobactéries — Un enjeu pour les biotechnologies
Résumé Les deux principales maladies à mycobactéries — la tuberculose et la lèpre — sont toujours des causes majeures de souffrance humaine dans de nombreuses parties du monde. La lutte contre ces maladies est entravée par l'inadéquation des méthodes diagnostiques, préventives et thérapeutiques. Spéciallement en ce qui concerne la tuberculose, l'amélioration des moyens de diagnostic est rendue nécessaire par le fait que les techniques bactériologiques existantes sont longues et peu sensibles, et que les tests immunologiques, n'étant pas spécifiques, ne permettent pas de distinguer entre une maladie en évolution et une sensibilisation ancienne. On a besoin de tests permettant de déceler soit la présence d'antigènes mycobactériens, soit l'apparition de réactions immunitaires spécifiques au cours d'une infection évolutive. La prophylaxie par le BCG n'est jamais complète et parait être pratiquement inefficace dans certaines régions. Pour expliquer cette variation géographique, produire de meilleurs vaccins, et utiliser le BCG efficacement, il convient de mieux connaître les réactions immunitaires au cours des maladies à mycobactéries. En particulier, les déterminants bactériens de la virulence et de la protection, ainsi que le mode d'action du BCG sont à approfondir. La rifampicine a considérablement transformé la thérapeutique de la tuberculose et, à un moindre degré, de la lèpre. Néanmoins, le coût des nouveaux traitements intensifs de la tuberculose limite leur application. Il est nécessaire que des médicaments bactéricides plus puissants ou des agents stimulant les défenses de l'hôte puissent raccourcir encore davantage la durée des traitements. Le progrès biotechnologique peut donc améliorer de façon significative le contrôle des maladies considérées, à la seule condition que ce but soit volontairement intégré dans les initiatives locales en matière de santé publique.
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Information specificity can be important to animals in makingoptimal decisions. However, it is not always necessary to useevery level of specificity. We analyzed the response of thepredatory mite Phytoseiulus persimilis to plant-produced informationrelated to a nonprey herbivore. This predator is a specialistfeeding on spider mites in the genus Tetranychus. Caterpillarsof Spodoptera exigua cannot serve as prey. Plants respond toan infestation by herbivores with the emission of volatilesthat attract carnivorous enemies of the herbivores. Conspecific plants infested with different herbivore species can emit blendsthat are qualitatively identical, while differing in the ratiosof blend components. However, different plant species emitvolatile blends that differ qualitatively. We demonstratedthat the predator P. persimilis is attracted to volatiles frombean plants infested with S. exigua caterpillars, but thatthis attraction is affected by predator starvation and host-plantexperience. One-hour and 24-h starved predators were made to represent predators that just lost a prey patch versus predatorsthat have totally lost a prey patch. Predators reared on spidermites on bean were attracted to bean plants infested with caterpillarswhen starved for 1 h but not when starved for 24 h. Both predatorgroups were attracted to bean plants infested with prey (i.e.,spider mites). One-hour starved predators can use the odorto relocate the rewarding prey patch they just lost contactwith, and using a general olfactory representation of the blendis sufficient for relocation. In contrast, for 24-h starvedpredators, the perception of a plant's odor blend is unlikelyto represent the prey patch lost, and discriminating betweenan odor blend representing prey or nonprey will avoid investingtime in finding a nonprey herbivore. In contrast, predatorsthat had been reared on spider mites on cucumber and thus hadexperienced a qualitatively different odor blend were not attractedto volatiles from caterpillar-infested bean plants. They wereattracted to spider mite-infested bean plants, irrespectiveof starvation level. To cucumber-experienced predators, theperception of bean plant odor cannot represent the prey patch lost, but only a new prey patch. Being discriminative and onlyresponding to prey-infested plants is adaptive in this situation.Our results are discussed in the context of optimal informationprocessing.  相似文献   

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