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1.
Self-Determination vs. Family-Determination: Two Incommensurable Principles of Autonomy 总被引:3,自引:0,他引:3
Ruiping Fan 《Bioethics》1997,11(3&4):309-322
Most contemporary bioethicists believe that Western bioethical principles, such as the principle of autonomy, are universally binding wherever bioethics is found. According to these bioethicists, these principles may be subject to culturally-conditioned further interpretations for their application in different nations or regions, but an 'abstract content' of each principle remains unchanged, which provides 'an objective basis for moral judgment and international law'. This essay intends to demonstrate that this is not the case. Taking the principle of autonomy as an example, this essay argues that there is no such shared 'abstract content' between the Western bioethical principle of autonomy and the East Asian bioethical principle of autonomy. Other things being equal, the Western principle of autonomy demands self-determination, assumes a subjective conception of the good and promotes the value of individual independence, whilst the East Asian principle of autonomy requires family-determination, presupposes an objective conception of the good and upholds the value of harmonious dependence. They differ from each other in the most general sense and basic moral requirement. 相似文献
2.
Fan R 《Bioethics》1997,11(3-4):309-322
Most contemporary bioethicists believe that Western bioethical principles, such as the principle of autonomy, are universally binding wherever bioethics is found. According to these bioethicists, these principles may be subject to culturally-conditioned further interpretations for their application in different nations or regions, but an 'abstract content' of each principle remains unchanged, which provides 'an objective basis for moral judgment and international law'. This essay intends to demonstrate that this is not the case. Taking the principle of autonomy as an example, this essay argues that there is no such shared 'abstract content' between the Western bioethical principle of autonomy and the East Asian bioethical principle of autonomy. Other things being equal, the Western principle of autonomy demands self-determination, assumes a subjective conception of the good and promotes the value of individual independence, whilst the East Asian principle of autonomy requires family-determination, presupposes an objective conception of the good and upholds the value of harmonious dependence. They differ from each other in the most general sense and basic moral requirement. 相似文献
3.
JAKOB ELSTER 《Bioethics》2011,25(9):482-488
Recently, Julian Savulescu and Guy Kahane have defended the Principle of Procreative Beneficence (PB), according to which prospective parents ought to select children with the view that their future child has ‘the best chance of the best life’. I argue that the arguments Savulescu and Kahane adduce in favour of PB equally well support what I call the Principle of General Procreative Beneficence (GPB). GPB states that couples ought to select children in view of maximizing the overall expected value in the world, not just the welfare of their future child. I further argue that Savulescu and Kahane's claim that PB has significantly more weight than competing moral principles, such as GPB, lacks justification. A possible argument for PB having significant weight builds on a principle of parental partiality towards one's own children. But this principle does not support PB; it supports a Principle of Sibling‐Oriented Procreative Beneficence (SPB), according to which parents selecting a child should maximize the benefit of all their children. Indeed, PB itself will in some cases be self‐effacing in favour of SPB. 相似文献
4.
Bo Zhang Yonggao Yu Jiadong Zhou Zhenfeng Wang Haoran Tang Shenkun Xie Zengqi Xie Liuyong Hu Hin‐Lap Yip Long Ye Harald Ade Zhitian Liu Zhicai He Chunhui Duan Fei Huang Yong Cao 《Liver Transplantation》2020,10(12)
In this contribution, a versatile building block, 3,4‐dicyanothiophene (DCT), which possesses structural simplicity and synthetic accessibility for constructing high‐performance, low‐cost, wide‐bandgap conjugated polymers for use as donors in polymer solar cells (PSCs), is reported. A prototype polymer, PB3TCN‐C66, and its cyano‐free analogue polymer PB3T‐C66, are synthesized to evaluate the potential of using DCT in nonfullerene PSCs. A stronger aggregation property in solution, higher thermal transition temperatures with higher enthalpies, a larger dipole moment, higher relative dielectric constant, and more linear conformation are exhibited by PB3TCN‐C66. Solar cells employing IT‐4F as the electron acceptor offer power conversion efficiencies (PCEs) of 11.2% and 2.3% for PB3TCN‐C66 and PB3T‐C66, respectively. Morphological characterizations reveal that the PB3TCN‐C66:IT‐4F blend exhibits better π–π paracrystallinity, a contracted domain size, and higher phase purity, consistent with its higher molecular interaction parameter, derived from thermodynamic calculations. Moreover, PB3TCN‐C66 offers a higher open‐circuit voltage and reduced energy loss than most state‐of‐the‐art wide‐bandgap polymers, without the need of additional electron‐withdrawing substituents. Two additional polymers derived from DCT also demonstrate promising performance with a higher PCE of 13.4% being achieved. Thus, DCT represents a versatile and promising building block for constructing high‐performance, low‐cost, conjugated polymers for application in PSCs. 相似文献
5.
Justice and equal opportunities in health care 总被引:2,自引:0,他引:2
Harris J 《Bioethics》1999,13(5):392-404
The principle that each individual is entitled to an equal opportunity to benefit from any public health care system, and that this entitlement is proportionate neither to the size of their chance of benefitting, nor to the quality of the benefit, nor to the length of lifetime remaining in which that benefit may be enjoyed, runs counter to most current thinking about the allocation of resources for health care. It is my contention that any system of prioritisation of the resources available for healthcare or of rationing such resources must be governed by this principle.
This can have apparently paradoxical conclusions in that it can seem wasteful to give someone with a very slim chance of a lifesaving treatment the same priority as someone with a much better chance. In an important and thoughtful recent paper, Julian Savulescu has concentrated on this apparent weakness and has argued for a particular conception of the good or benefit to be achieved by a healthcare system which purports to demonstrate the inadequacies of an equal opportunities approach to prioritisation and to replace it with an altogether better account. This paper will show that a rational 'reasons based consequentialism' is more in line with the equal opportunities approach, which I defended some time ago in these pages, than with that of Savulescu. I shall then examine more closely the conception of equal opportunities in health care and show that if we give weight to an individual's reasons, and what is expected to be good for them, we will opt for exactly the equality based account of distributive justice that I have recommended. 相似文献
This can have apparently paradoxical conclusions in that it can seem wasteful to give someone with a very slim chance of a lifesaving treatment the same priority as someone with a much better chance. In an important and thoughtful recent paper, Julian Savulescu has concentrated on this apparent weakness and has argued for a particular conception of the good or benefit to be achieved by a healthcare system which purports to demonstrate the inadequacies of an equal opportunities approach to prioritisation and to replace it with an altogether better account. This paper will show that a rational 'reasons based consequentialism' is more in line with the equal opportunities approach, which I defended some time ago in these pages, than with that of Savulescu. I shall then examine more closely the conception of equal opportunities in health care and show that if we give weight to an individual's reasons, and what is expected to be good for them, we will opt for exactly the equality based account of distributive justice that I have recommended. 相似文献
6.
Caroline Harnacke 《Bioethics》2016,30(3):141-150
The ‘Ashley treatment’ (growth attenuation, removal of the womb and breasts buds of a severely disabled child) has raised much ethical controversy. This article starts from the observation that this debate suffers from a lack of careful philosophical analysis which is essential for an ethical assessment. I focus on two central arguments in the debate, namely an argument defending the treatment based on quality of life and an argument against the treatment based on dignity and rights. My analysis raises doubts as to whether these arguments, as they stand in the debate, are philosophically robust. I reconstruct what form good arguments for and against the treatment should take and which assumptions are needed to defend the according positions. Concerning quality of life (Section 2), I argue that to make a discussion about quality of life possible, it needs to be clear which particular conception of the good life is employed. This has not been sufficiently clear in the debate. I fill this lacuna. Regarding rights and dignity (section 3), I show that there is a remarkable absence of references to general philosophical theories of rights and dignity in the debate about the Ashley treatment. Consequently, this argument against the treatment is not sufficiently developed. I clarify how such an argument should proceed. Such a detailed analysis of arguments is necessary to clear up some confusions and ambiguities in the debate and to shed light on the dilemma that caretakers of severely disabled children face. 相似文献
7.
Andrew Hotke 《Bioethics》2014,28(5):255-262
In the last ten years, there have been a number of attempts to refute Julian Savulescu's Principle of Procreative Beneficence; a principle which claims that parents have a moral obligation to have the best child that they can possibly have. So far, no arguments against this principle have succeeded at refuting it. This paper tries to explain the shortcomings of some of the more notable arguments against this principle. I attempt to break down the argument for the principle and in doing so, I explain what is needed to properly refute it. This helps me show how and why the arguments of Rebecca Bennett, Sarah Stoller and others fail to refute the principle. Afterwards, I offer a new challenge to the principle. I attack what I understand to be a fundamental premise of the argument, a premise which has been overlooked in the literature written about this principle. I argue that there is no reason to suppose, as Savulescu does, that morality requires us to do what we have most reason to do. If we reject this premise, as I believe we have reason to do, the argument for Procreative Beneficence fails. 相似文献
8.
Stephanie Pincetl Mikhail Chester Giovanni Circella Andrew Fraser Caroline Mini Sinnott Murphy Janet Reyna Deepak Sivaraman 《Journal of Industrial Ecology》2014,18(6):871-882
This synthesis article presents an overview of an urban metabolism (UM) approach using mixed methods and multiple sources of data for Los Angeles, California. We examine electric energy use in buildings and greenhouse gas emissions from electricity, and calculate embedded infrastructure life cycle effects, water use and solid waste streams in an attempt to better understand the urban flows and sinks in the Los Angeles region (city and county). This quantification is being conducted to help policy‐makers better target energy conservation and efficiency programs, pinpoint best locations for distributed solar generation, and support the development of policies for greater environmental sustainability. It provides a framework to which many more UM flows can be added to create greater understanding of the study area's resource dependencies. Going forward, together with policy analysis, UM can help untangle the complex intertwined resource dependencies that cities must address as they attempt to increase their environmental sustainability. 相似文献
9.
Ben Saunders 《Bioethics》2021,35(1):90-97
Douglas Diekema influentially argues that interference with parental decisions is not in fact guided by the child’s best interests, but rather by a more permissive standard, which he calls the harm principle. This article first seeks to clarify this alternative position and defend it against certain existing criticisms, before offering a new criticism and alternative. This ‘harm principle’ has been criticized for (i) lack of adequate moral grounding, and (ii) being as indeterminate as the best interest standard that it seeks to replace. I argue that these are not serious problems. I take Diekema’s negative point to be right—our actual standard for intervention is not literally the best interests of the child—but I disagree with his proposed replacement. First, Diekema’s proposed harm threshold should be more carefully distinguished from Mill’s harm principle. Second, there is no reason to assume that the standard for permissible intervention coincides with the threshold for harm (or serious harm). Thus, I propose that the best alternative to the best interests standard is not a harm principle, but rather a sufficiency threshold between adequate (or ‘good enough’) and inadequate (or ‘substandard’) parenting. 相似文献
10.
Pavlinov IIa 《Zhurnal obshche? biologii》2006,67(2):83-106
Rise of non-classical science during XX century had certain influence upon development of biological taxonomy. Scientific pluralism (especially normative naturalism of Laudan), contrary to positivist and early post-positivist treatments, made taxonomy acknowledged scientific discipline of its own right. The present state of some schools of taxonomy makes it possible to consider them as a part of non-classical science and constituting the non-classical taxonomy. The latter is characterized by the following most important features. Ontological substantiation of both classificatory approaches and particular classifications is requested which invalidates such formal approaches as nominalistic and phenetic (numerical) schools. This substantiation takes a form of content-wise background preferably causal models which include certain axioms and presumptions about taxonomic diversity being studied, together with its causes, and thus define initial conditions of classificatory procedures. From this viewoint, phylogenetic classificatory approach is the most developed part of non-classical taxonomy. The entire taxonomic diversity is structured into several aspects of different levels of generality, each being outlined by a particular consideration aspect. The latter makes personal knowledge constituting an irremovable part of any scientific statement about taxonomic diversity, thus opposition of "objectively" and "subjectively" elaborated classifications becomes vague. Interrelation of various species concepts corresponding to its different consideration aspects is described by uncertainty relation principle. Classificatory algorithms are to be compatible with the conditions of a background model to ensure particular classifications obtained by their means are interpretable within the same model: this is provided by the correspondence principle. Classification is considered as a taxonomic hypothesis, i.e. a conjectural judgement about structure of particular fragment of taxonomic diversity considered within given consideration aspect; wich is to be forwarded and tested according to certain rules. Recognition of different aspects of taxonomic diversity makes it "legal" to elaborate several classifications of equal status, each reflecting a particular aspect of a fixed fragment of that diversity. This viewpoint makes classical ideas of the "ultimate" Natural (whatever might be its definition) or the best reference systems futile. In general, any pretension of an approach to be "the best" in reflecting taxonomic divesrity is contr-productive. Instead, elaboration of particular spectra of complementary classifications becomes the main task of non-classical taxonomy which describes in sum the entire taxonomic diversity. So, not opposition but correct mutual interpretation of such classifications and uniting them into the comprehensive picture of taxonomic diversity become focal points of non-classical taxonomy. 相似文献
11.
Procreative beneficence: why we should select the best children 总被引:8,自引:0,他引:8
Savulescu J 《Bioethics》2001,15(5-6):413-426
Eugenic selection of embryos is now possible by employing in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD). While PGD is currently being employed for the purposes of detecting chromosomal abnormalities or inherited genetic abnormalities, it could in principle be used to test any genetic trait such as hair colour or eye colour.
Genetic research is rapidly progressing into the genetic basis of complex traits like intelligence and a gene has been identified for criminal behaviour in one family. Once the decision to have IVF is made, PGD has few 'costs' to couples, and people would be more inclined to use it to select less serious medical traits, such as a lower risk of developing Alzheimer Disease, or even for non-medical traits. PGD has already been used to select embryos of a desired gender in the absence of any history of sex-linked genetic disease.
I will argue that: (1) some non-disease genes affect the likelihood of us leading the best life; (2) we have a reason to use information which is available about such genes in our reproductive decision-making; (3) couples should select embryos or fetuses which are most likely to have the best life, based on available genetic information, including information about non-disease genes. I will also argue that we should allow selection for non-disease genes even if this maintains or increases social inequality. I will focus on genes for intelligence and sex selection.
I will defend a principle which I call Procreative Beneficence: couples (or single reproducers) should select the child, of the possible children they could have, who is expected to have the best life, or at least as good a life as the others, based on the relevant, available information. 相似文献
Genetic research is rapidly progressing into the genetic basis of complex traits like intelligence and a gene has been identified for criminal behaviour in one family. Once the decision to have IVF is made, PGD has few 'costs' to couples, and people would be more inclined to use it to select less serious medical traits, such as a lower risk of developing Alzheimer Disease, or even for non-medical traits. PGD has already been used to select embryos of a desired gender in the absence of any history of sex-linked genetic disease.
I will argue that: (1) some non-disease genes affect the likelihood of us leading the best life; (2) we have a reason to use information which is available about such genes in our reproductive decision-making; (3) couples should select embryos or fetuses which are most likely to have the best life, based on available genetic information, including information about non-disease genes. I will also argue that we should allow selection for non-disease genes even if this maintains or increases social inequality. I will focus on genes for intelligence and sex selection.
I will defend a principle which I call Procreative Beneficence: couples (or single reproducers) should select the child, of the possible children they could have, who is expected to have the best life, or at least as good a life as the others, based on the relevant, available information. 相似文献
12.
Jasmina Vidic Charles-Adrien Richard Christine Péchoux Bruno Da Costa Nicolas Bertho Sandra Mazerat Bernard Delmas Christophe Chevalier 《The Journal of biological chemistry》2016,291(2):739-751
PB1-F2 is a small accessory protein encoded by an alternative open reading frame in PB1 segments of most influenza A virus. PB1-F2 is involved in virulence by inducing mitochondria-mediated immune cells apoptosis, increasing inflammation, and enhancing predisposition to secondary bacterial infections. Using biophysical approaches we characterized membrane disruptive activity of the full-length PB1-F2 (90 amino acids), its N-terminal domain (52 amino acids), expressed by currently circulating H1N1 viruses, and its C-terminal domain (38 amino acids). Both full-length and N-terminal domain of PB1-F2 are soluble at pH values ≤6, whereas the C-terminal fragment was found soluble only at pH ≤ 3. All three peptides are intrinsically disordered. At pH ≥ 7, the C-terminal part of PB1-F2 spontaneously switches to amyloid oligomers, whereas full-length and the N-terminal domain of PB1-F2 aggregate to amorphous structures. When incubated with anionic liposomes at pH 5, full-length and the C-terminal part of PB1-F2 assemble into amyloid structures and disrupt membrane at nanomolar concentrations. PB1-F2 and its C-terminal exhibit no significant antimicrobial activity. When added in the culture medium of mammalian cells, PB1-F2 amorphous aggregates show no cytotoxicity, whereas PB1-F2 pre-assembled into amyloid oligomers or fragmented nanoscaled fibrils was highly cytotoxic. Furthermore, the formation of PB1-F2 amyloid oligomers in infected cells was directly reflected by membrane disruption and cell death as observed in U937 and A549 cells. Altogether our results demonstrate that membrane-lytic activity of PB1-F2 is closely linked to supramolecular organization of the protein. 相似文献
13.
M. MacGarvin 《Helgoland Marine Research》1995,49(1-4):647-662
Marine biological monitoring programmes frequently attempt to determine “safe” levels of contamination, based on assumptions
about the assimilative capacity of the environment. This paper argues that such assumptions lack scientific rigour, and do
not form the basis upon which a precautionary policy can be built. It notes the problems associated with assessing toxicological
effects, but centres its attention on the crucial (yet far less discussed) weaknesses in theoretical ecology that make it
extremely unlikely that biological monitoring can determine safe levels of contamination that leave ecosystems unaffected.
It is argued that many marine biologists, if pressed, would concede these shortcomings but believe that, in the face of the
technical difficulties and high costs of pollution prevention, we have no choice but to use such methods. This paper argues,
with examples, that pollution prevention, often with considerable economic savings, is becoming a reality for even the most
problematic substances. The difficulty is that the development of “clean production” methods lie outside the sphere of interest
of those carrying out monitoring, so that measures that attempt to determine safe levels of contamination continue to be advocated.
This gulf needs to be bridged so that the continuation of monitoring programmes that are part of dilute and disperse policies
become regarded as inappropriate, indeed unethical. The paper concludes that this does not mean the end of marine monitoring.
Instead, reliable methods for assessing physical levels of contamination will be required to determine whether the reduction
targets set—as part of the introduction of clean production—are being met. Formidable difficulties will remain, requiring
a precautious approach. Nevertheless, monitoring will no longer carry the burden of attempting to demonstrate that a particular
level of environmental contamination is safe, which is currently destroying its scientific credibility. 相似文献
14.
ALBERT GARTH THOMAS 《Bioethics》2012,26(2):101-107
The President's Council on Bioethics has recently released a report supportive of the continued use of brain death as a criterion for human death. The Council's conclusions were based on a conception of life that stressed external work as the fundamental marker of organismic life. With respect to human life, it is spontaneous respiration in particular that indicates an ability to interact with the external environment, and so indicates the presence of life. Conversely, irreversible apnoea marks an inability to carry out the necessary work of life, an inability which the Council considers an indicator of death. This conception has been conceived to circumvent criticisms of the previous model of loss of somatic integration, a model the Council admits that, in the presence of evidence of continuing functional integration in brain dead patients, was looking less than convincing. Nevertheless, by focusing on external work and ignoring the more essential work of integrative unity, the Council's conception of the nature of life is untenable, and of no assistance in supporting a relation of equivalence between the concepts of brain death and death. Consequently, the Council's conclusions do little to advance the definition of death debate, a potentially intractable debate that may necessitate the investigation of alternate ethical justifications for organ harvesting. 相似文献
15.
Jukka Varelius 《Bioethics》2019,33(1):195-200
In the end‐of‐life context, alleviation of the suffering of a distressed patient is usually seen as a, if not the, central goal for the medical personnel treating her. Yet it has also been argued that suffering should be seen as a part of good dying. More precisely, it has been maintained that alleviating a dying patient’s suffering can make her unable to take care of practical end‐of‐life matters, deprive her of an opportunity to ask questions about and find meaning in and for her existence, and detach her from reality. In this article, I argue that the aims referred to either do not support suffering or are better served by alleviating it. When the aims would be equally well served by enduring suffering and relieving it, the latter appears to be the preferable option, given that the distress a patient experiences has no positive intrinsic value. Indeed, as the suffering can be very distressing, it may not be worth bearing even if that was the best way to achieve the aims: the distress can sometimes be bad enough to outbalance the worth of achieving the goals. Having considered an objection to the effect that a patient can have a self‐regarding moral duty to endure the distress she faces at the end of life, I conclude that the burden of proof is on the side of those who maintain that the suffering experienced at the end of life ought to be endured as a part of dying well. 相似文献
16.
Den Hartogh G 《Bioethics》1997,11(1):43-66
In Life's Dominion Dworkin aims at defusing the controversy about abortion and euthanasia by redefining its terms. Basically it is not a dispute about the right to life, but about its value. Liberals should grant that human life has not only a personal, but also an intrinsic value; conservatives should accept the principle of toleration which requires to let people decide for themselves about matters of intrinsic value. Dworkin fails, however, to distinguish between two kinds of personal value: (1) the value of something to a person, when he actually or dispositionally desires it, or finds it pleasant; and (2) the value of something to a person, when it's objectively contributes to his well-being, as defined by reference to his personal point of view, whether or not he ever perceives it as so contributing. He also fails to distinguish between two meanings of the concept of 'intrinsic value': (3) ultimate, i.e. non-instrumental personal value of kind (2); (4) the impersonal value of something which is not good-for-anybody, but simply good, i.e. not a constituent of someone's well-being. Dworkin argues that the human fetus from conception onwards has a value, that it is not a personal value of kind (1), and therefore must be an intrinsic value. But the value of the life of the fetus is not a personal value of kind (2) either and therefore not an intrinsic value of kind (3): it is normally a constituent of the well-being of the pregnant woman, but that doesn't constitute its value, and it is not good 'for' the fetus itself in the relevant sense, because it doesn't have a personal point of view. If, however, the fetus' life is allowed to have an intrinsic value of kind (4), the conservative cannot be refuted by appeal to the principle of toleration, for this only concerns intrinsic value of kind (3). The liberal, indeed, should recognize that the fetus' life has a value, but it is neither a personal value (1) or (2), nor an impersonal value (4), but rather a relational value which gradually develops from some point substantially later than conception. 相似文献
17.
Breeding behavior of female white‐tailed deer relative to conception: Evidence for female mate choice
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Jeffery D. Sullivan Stephen S. Ditchkoff Bret A. Collier Charles R. Ruth Joshua B. Raglin 《Ecology and evolution》2017,7(7):2395-2402
Female white‐tailed deer (Odocoileus virginianus) are thought to choose between two behavioral strategies to maximize the quality of potential mates: sit and wait, characterized by concentrating activity within a restricted area, and excursive behavior, characterized by increased activity and excursions outside the home range. As movement patterns may influence conception, our goal was to examine the patterns of female white‐tailed deer movements to evaluate which breeding strategy was employed. We equipped 36 female white‐tailed deer with GPS collars from August 2013 to December 2015. We found that movement rate and probability of activity were greatest near the peak of the breeding season, and we observed increases in both metrics during the 40 days prior to estimated conception. Peak size of home range and core area occurred in the days surrounding conception. We found that 11 deer performed an excursion, ranging from 43 days before until 36 days after conception, with the peak probability of being outside of an individual home range occurring 1 day prior to conception. Our results suggest that female white‐tailed deer may attempt to maximize the quality of their mates by advertising availability for breeding through excursive behaviors just prior to entering estrus. 相似文献
18.
Improved Electrochemical Performance of Na‐Ion Batteries in Ether‐Based Electrolytes: A Case Study of ZnS Nanospheres
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Sodium‐ion batteries are considered as a promising technology for large‐scale energy storage applications, owing to their low cost. However, there are many challenges for developing sodium‐ion batteries with high capacity, long cycle life, and high‐rate capability. Herein, the development of high‐performance sodium‐ion batteries using ZnS nanospheres as anode material and an ether‐based electrolyte, which exhibit improved electrochemical performance over the pure alkyl carbonate electrolytes, is reported. ZnS nanospheres deliver a high specific capacity of 1000 mA h g?1 and high initial Columbic efficiency of 90%. Electrochemical testing and first‐principle calculations demonstrate that the ether‐based solvent can facilitate charge transport, reduce the energy barrier for sodium‐ion diffusion, and thus enhance electrochemical performances. Ex situ measurements (X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) mapping) reveal that ZnS nanospheres maintain structural integrity during the charge and discharge processes over 100 cycles. As anode material for sodium‐ion batteries, ZnS nanospheres deliver high reversible sodium storage capacity, high Coulombic efficiencies, and extended cycle life. 相似文献
19.
Milkevitch M Shim H Pilatus U Pickup S Wehrle JP Samid D Poptani H Glickson JD Delikatny EJ 《Biochimica et biophysica acta》2005,1734(1):1-12
DU145 human prostatic carcinoma cells were treated with the differentiating agents phenylacetate (PA) and phenylbutyrate (PB) and examined in perfused cultures by diffusion-weighted 1H and 31P nuclear magnetic resonance spectroscopy (NMR). PA and PB (10 mM) induced significant (>3-fold) time-dependent increases in the level of NMR-visible lipids and total choline in 1H spectra, and glycerophosphocholine levels in the 31P spectra, with the increases being greater for PB. These effects were accompanied by significant increases in cytoplasmic lipid droplets and intracellular lipid volume fraction as observed by morphometric analysis of Oil Red O-stained cells. PB treatment caused cell cycle arrest in the G1 phase and induction of apoptosis. In contrast, PA-treated DU145 cells showed an accumulation of cells in G2/M and no evidence of apoptosis. These results demonstrate that significant differences exist in the mechanism of PA and PB activity, although both compounds cause similar, but graded alterations in lipid metabolism. The simultaneous accumulation of mobile lipid and glycerophosphocholine suggests that PB and PA induce phospholipid catabolism via a phospholipase-mediated pathway. The mobile lipid accumulation following the induction of either apoptosis and cytostasis by related differentiating agents indicate that the presence of NMR-visible lipids may not be a specific event causally resulting from the induction of apoptosis. 相似文献
20.
Golovlev EL 《Mikrobiologiia》2001,70(4):437-443
An attempt is made to sum up the results of the many years of using the conception of ecological strategy in bacterial ecology. Taking into account the specificities of microorganisms and their natural selection and the coevolution of microorganisms within evolving microbial communities, an inference is derived that the ecological strategy of most bacteria is the sum of a number of particular canonical strategies, some of which are common to higher organisms. It is proposed to term these particular strategies ecological tactics. The author considers this review as a basis for discussion. 相似文献