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1.
Darwin’s treatment of morality in The Descent of Man has generated a wide variety of responses among moral philosophers. Among these is the dismissal of evolution as irrelevant to ethics by Darwin’s contemporary Henry Sidgwick; the last, and arguably the greatest, of the Nineteenth Century British Utilitarians. This paper offers a re-examination of Sidgwick’s response to evolutionary considerations as irrelevant to ethics and the absence of any engagement with Darwin’s work in Sidgwick’s main ethical treatise, The Methods of Ethics. This assessment of Sidgwick’s response to Darwin’s work is shown to have significance for a number of ongoing controversies in contemporary metaethics.  相似文献   

2.
The effect of change of number of OTU’s (operational taxonomic units) in a numerical taxonomic study was investigated using 28 taxospecies of the genusSalix in California and 22 sites of sect.Sitchenses of the genus. A coefficient of Euclidean distance was used to estimate relationships among the OTU’s based on 99 morphological characters. Two methods of clustering were employed: 1) Tryon’s key communality cluster analysis, and 2) the unweighted pair group method. The latter results in a phenogram. It was found that the number of OTU’s employed does make a difference. But the difference is not random and is centered around those OTU’s most closely related to the OTU’s being added.  相似文献   

3.
河南省淮河流域鳑鲏亚科5种鱼形态差异分析   总被引:1,自引:0,他引:1  
为进一步从可量性状比较中华鳑鲏(Rhodeus sinensis)、越南鱊(Acheilongnathus tonkinensis)、大鳍鱊(A. macropterus)、兴凯鱊(A. chankaensis)和斑条鱊(A. taenianalis)的种间形态差异, 丰富鳑鲏亚科鱼类的形态分类特征, 研究采用多变量形态度量学方法对河南省淮河流域这5种鱼的形态进行比较分析。结果表明: 这5种鱼在体宽/体长、头长/体长、吻长/体长、尾柄长/体长、背鳍基底长/体长、腹鳍长/体长、臀鳍长/体长和头长/吻长8个比值性状上存在极显著性差异(P< 0.01), 在全长/体长、体高/体长2个比值性状上存在显著性差异(P<0.05), 这些差异主要集中在鱼体的头部、尾部和鳍等部位。主成分分析、聚类分析和判别分析显示5种鱼存在显著性形态差异, 斑条鱊与越南鱊的差异程度最大, 与大鳍鱊差异程度最小。判别分析获得的判别准确率在82.35%—100.00%变化, 可以从一定的角度区分这5种鱼。  相似文献   

4.
ABSTRACT

This article takes the occasion of the publication of two lengthy volumes about the life and work of Claude Lévi-Strauss to assess certain elements of Maurice Godelier’s Marxist encounter with structuralism. While providing an overall view of each book, and the way they speak to each other, I also explore particular dimensions of Godelier’s engagement with Lévi-Strauss, including in relation to Godelier’s attempt to introduce psychoanalysis into his Marxist-structuralist equations. Four broad themes are addressed: the horizontal and vertical dimensions of kinship as alliance and descent; domination and the so-called ‘exchange of women’; Godelier’s limited appeal to Freud, especially in relation to his near occlusion of Lacan; and Godelier’s ‘suspicious’ humanist relationship to sacred belief as ideological illusion. This last matter leads to a concluding section which, drawing on Loyer’s biography, contrasts Godelier’s version of late Enlightenment humanism with what was arguably the more radically expanded humanism of the mature Lévi-Strauss.  相似文献   

5.
Objective: The effect of Helicobacter pylori on Barrett’s esophagus is poorly understood. We conducted a meta‐analysis to summarize the existing literature examining the effect that H. pylori has on Barrett’s esophagus. Design: We performed a comprehensive search to identify studies pertaining to the association between H. pylori and Barrett’s esophagus. We conducted meta‐regression analyses to identify sources of variation in the effect of H. pylori on Barrett’s esophagus. Results: Our analysis included a total of 49 studies that examined the effect of H. pylori on Barrett’s esophagus and seven studies that examined the effect of cag A positivity on Barrett’s esophagus. Overall, H. pylori, and even more so cag A, tended to be protective for Barrett’s esophagus in most studies; however, there was obvious heterogeneity across studies. The effect of H. pylori on Barrett’s esophagus varied by geographic location and in the presence of selection and information biases. Only four studies were found without obvious selection and information bias, and these showed a protective effect of H. pylori on Barrett’s esophagus (Relative risk = 0.46 [95% CI: 0.35, 0.60]). Conclusions: Estimates for the effect of H. pylori on Barrett’s esophagus were heterogeneous across studies. We identified selection and information bias as potential sources of this heterogeneity. Few studies without obvious selection and information bias have been conducted to examine the effect of H. pylori on Barrett’s esophagus, but in these, H. pylori infection is associated with a reduced risk of Barrett’s esophagus.  相似文献   

6.

Several recent studies have suggested past gene flow between the Przewalski’s horse and modern domestic horse and questioned the wild origin of the Przewalski’s horse. Mitochondrial DNA has placed representatives of the Przewalski’s horse into three among the eighteen haplogroups detected from the modern horse. Of these, two haplogroups have so far been found exclusively in the Przewalski’s horse, while the one shared with the domestic horse includes captive individuals that have uncertain pedigrees. We recently found five domestic horse individuals of North European horse breeds to carry a mitochondrial haplogroup that was previously confined only to the Przewalski’s horse. These individuals were sequenced for 6039 bp of mitochondrial DNA and used, together with domestic and Przewalski’s horse sequences presenting all horse haplogroups, to examine the phylogenetic relationships and to date the divergence time between Przewalski’s and domestic horse clusters within this haplogroup. The divergence was dated to have likely occurred about 13,300–11,400 years ago, which coincides with the time of the Younger Dryas.

  相似文献   

7.
IntroductionProstate cancer growth and progression may be linked to neurogenesis and to medical anti- Parkinson treatment, but results are inconclusive. Therefore, we examined the association between Parkinson’s disease and risk of prostate cancer in a population based case-control study.MethodsWe identified 45,429 patients diagnosed with incident prostate cancer during 1997–2010 from the National Cancer Registry. Five age-matched population controls (n = 227,145) were selected for each case. Odds ratios (ORs) adjusted for age and comorbidity for prostate cancer associated with Parkinson’s disease were computed using conditional logistic regression. Analyses were stratified by duration of Parkinson’s disease and stage of prostate cancer (localized and advanced).ResultsIn total, 245 patients (0,5%) and 1656 controls (0,7%) had Parkinson’s disease. Overall, patients with Parkinson’s disease had a 27% lower risk of prostate cancer compared with patients without Parkinson’s disease (adjusted OR (ORa) 0.73; 95% confidence interval (CI), 0.63–0.83).Risk of prostate cancer decreased with increasing duration of Parkinson’s disease.The odds ratios were slightly lower for advanced prostate cancer (ORa, 0.68; 95% CI, 0.52–0.88) than for localized prostate cancer (ORa 0.76; 95% CI, 0.61–0.93).ConclusionParkinson’s disease was associated with a risk reduction overall (27%), which decreased with increasing duration of Parkinson’s disease.  相似文献   

8.
Phytoprostanes (PhytoP’s) are formed in higher plants from α-linolenic acid via a nonenzymatic free radical-catalyzed pathway and act as endogenous mediators capable of protecting cells from damage under various conditions related to oxidative stress. Humans are exposed to PhytoP’s, as they are present in relevant quantities in vegetable food and pollen. The uptake of PhytoP’s through the olfactory epithelium of the nasal mucosa, upon pollen grain inhalation, is of interest as the intranasal pathway is regarded as a direct route of communication between the environment and the brain. On this basis, we sought to investigate the potential activities of PhytoP’s on immature cells of the central nervous system, which are particularly susceptible to oxidative stress. In neuroblastoma SH-SY5Y cells, used as a model for undifferentiated neurons, B1-PhytoP’s, but not F1-PhytoP’s, increased cell metabolic activity and protected them from oxidant damage caused by H2O2. Moreover, B1-PhytoP’s induced a moderate depolarization of the mitochondrial inner membrane potential. These effects were prevented by the PPAR-γ antagonist GW9662. When SH-SY5Y cells were induced to differentiate toward a more mature phenotype, they became resistant to B1-PhytoP activities. B1-PhytoP’s also influenced immature cells of an oligodendroglial line, as they increased the metabolic activity of oligodendrocyte progenitors and strongly accelerated their differentiation to immature oligodendrocytes, through mechanisms at least partially dependent on PPAR-γ activity. However, B1-PhytoP’s did not protect oligodendrocyte progenitors against oxidant injury. Taken together, these data suggest that B1-PhytoP’s, through novel mechanisms involving PPAR-γ, can specifically affect immature brain cells, such as neuroblasts and oligodendrocyte progenitors, thereby conferring neuroprotection against oxidant injury and promoting myelination.  相似文献   

9.
In this paper I address an important question in Aristotle’s biology, What are the causal mechanisms behind the transmission of biological form? Aristotle’s answer to this question, I argue, is found in Generation of Animals Book 4 in connection with his investigation into the phenomenon of inheritance. There we are told that an organism’s reproductive material contains a set of “movements'' which are derived from the various “potentials'' of its nature (the internal principle of change that initiates and controls development). These “movements,'' I suggest, function as specialized vehicles for communicating the parts of the parent’s heritable form during the act of reproduction. After exploring the details of this mechanism, I then take up Aristotle’s theory of inheritance proper. At the heart of the theory are three general principles (or ‘laws’) that govern the interactions between the maternal and paternal movements, the outcome of which determines the pattern of inheritance for the offspring. Although this paper is primarily aimed at providing a detailed analysis of Aristotle’s account of inheritance, the results of that analysis have implications for other areas of Aristotle’s biology. One of the most interesting of these is the question of whether Aristotle’s biology is anti-evolutionary (as traditionally assumed) or whether (as I argue) it leaves room for a theory of evolution by natural selection, even if Aristotle himself never took that step.  相似文献   

10.
《Plains anthropologist》2013,58(15):2-23
Abstract

A re-study based upon translations of the original documents is made of the many published routes suggested for Coronado’s and Oñate’s routes into the Plains. The point is made that disagreements among historians stem from the differing initial point of reference, a bridge thrown across a large river. Others have identified this river as the Pecos but Schroeder feels the evidence shows this is the Canadian River. Coronado’s route is then traced across the Plains to the Cimarron River. From this point to Quivira Schroeder is in agreement with other historians that the route was along the Arkansas River. He also agrees with Wedel’s archaeological location of Quivira as being in the Rice-McPherson County area of Kansas. The separate routes of Coronado’s army and party are then traced back to the Pecos Pueblo along what Schroeder deduces to have been more or less a straight line across the Oklahoma-Texas Panhandles.

Oñte’s later trip into the Plains is compared with Coronado’s. Considered in some detail are the intervening location of the Apachean and Plains Caddoan groups in relation to each other as suggested by the statements of the various chroniclers. The conclusion is reached that Oñate’s Quivira was located farther south than that visited by Coronado. Schroeder feels that Wedel’s archaeological work supports this view and concludes that Oñate’s Quivira extended slightly farther south along the Chicaskia River near Ponca City, Oklahoma.  相似文献   

11.
For decades historians of science and science writers in general have maintained that Charles Darwin was not the ‘naturalist’ or ‘official naturalist’ during the 1831–1836 surveying voyage of HMS Beagle but instead Captain Robert FitzRoy’s ‘companion’, ‘gentleman companion’ or ‘dining companion’. That is, Darwin was primarily the captain’s social companion and only secondarily and unofficially naturalist. Instead, it is usually maintained, the ship’s surgeon Robert McCormick was the official naturalist because this was the default or official practice at the time. Although these views have been repeated in countless accounts of Darwin’s life, this essay aims to show that they are incorrect.  相似文献   

12.
Le Pentatomidae (Insecta : Hemiptera) d’origine asiatique Halyomorpha halys (Stal 1855) a été trouvée en Ile de France (Paris intra muros et Lardy, Essonne) à la fin de l’année 2013. Ces occurrences font suite à celle de l’été 2013 dans l’agglomération de Strasbourg, près de la frontière allemande. Il s’agit de la 5e mention de cette espèce en Europe après la Suisse, l’Allemagne, et l’Italie. Il serait nécessaire de surveiller l’expansion de cette espèce polyphage et dommageable à des nombreuses cultures, dont l’expansion en Europe est très rapide, et qui peut être un agent allergénique.  相似文献   

13.
This paper analyzes the impact that Lamarckian evolutionary theory had in the scientific community during the period between the advent of Zoological Philosophy and the publication Origin of Species. During these 50 years Lamarck’s model was a well known theory and it was discussed by the scientific community as a hypothesis to explain the changing nature of the fossil record throughout the history of Earth. Lamarck’s transmutation theory established the foundation of an evolutionary model introducing a new way to research in nature. Darwin’s selectionist theory was proposed in 1859 to explain the origin of species within this epistemological process. In this context, Charles Lyell’s Principles of Geology and Auguste Comte’s Cours de Philosophie Positive appear as two major works for the dissemination of Lamarck’s evolutionary ideology after the death of the French naturalist in 1829.  相似文献   

14.
ABSTRACT

The 1913 volcanic eruption on the island of Ambrym (Vanuatu) struck both groups composing the island’s population at the time, the Islanders and the British Presbyterians who had come to ‘civilise’ them. Through the lens of Peirce’s semiosis, particularly his notion of the ‘indexical sign’, this article examines the chronological development of the two groups’ divergent, and also at times convergent interpretations of the eruption as a sign. This semiotic analysis is then extended into the island’s socio-historical context, from the Presbyterians’ first attempts at missions to the catastrophic upheaval that decimated the island’s population until the 1940s, to study how the two groups interpreted themselves, each other, Western Christianity and the traditional Ambrymese belief and authority system.  相似文献   

15.
Judith Woolf 《Anthrozo?s》2019,32(3):305-318
The paper considers the cultural exploitation of bears, especially white ones, from the late sixteenth century to the present, both in drama and literary fiction and in the bear pits, theatres, circuses, zoos, and natural habitats in which real biological bears have found themselves mythologized and marketed. Beginning and ending with Bryndís Snæbjörnsdóttir and Mark Wilson’s art project nanoq: flat out and bluesome (2006), the argument explores the use and abuse of fictive and real white bears in the changing contexts of Elizabethan and Jacobean politics and performance history, eighteenth and nineteenth century colonialism, and present day anxieties about habitat degradation and global warming, and also in the light of the perennial and “almost inescapable anthropomorphism” which, as Snæbjörnsdóttir and Wilson point out, causes us to see the bear as “a potent symbol” rather than a creature with its own life experience and autonomy. In addition to nanoq: flat out and bluesome, which attempts to break its audience out of that mind-set by confronting them with the mortal remains and individual histories of 34 taxidermic bears, the paper discusses George Peele’s The Old Wives Tale (c. 1594), the anonymous 1590s play Mucedorus, Ben Jonson’s masque Oberon, the Fairy Prince (1611), Laurence Sterne’s Tristram Shandy (1760), Robert Bage’s Jacobin novel Hermsprong (1796), James Hogg’s novella The Surpassing Adventures of Allan Gordon (1834), Philip Pullman’s Northern Lights (1995), Yoko Tawada’s Memoirs of a Polar Bear (2016), and Martin Rowe’s The Polar Bear in the Zoo (2013).  相似文献   

16.
Gerday  Colette  Juan  Caroline  Dubois  Michel  Demoulin  André 《Andrologie》1993,3(1):29-37
L’analyse de 1132 tentatives de FIV montre comment le taux de récolte détermine la fiabilité de l’estimation de l’échec de fécondation. L’étude de 64 couples ayant réalisé plusieurs tentatives dont une au moins s’est soldée par un échec de fécondation montre que 68,7% d’entre eux obtiennent des embryons lors d’une autre tentative. Les embryons replacés ont les mêmes aptitudes d’implantation et de développement que ceux obtenus par 130 couples ayant subi un premier échec d’implantation. Ces résultats sont mis en relation avec ceux obtenus par insémination subzonale après deux échecs de FIV.  相似文献   

17.
Les criquets représentent un taxon central dans les chaînes alimentaires et sont de bons indicateurs à la fois des caractéristiques des milieux et des perturbations de leurs habitats. Associés exclusivement aux habitats herbacés pérennes, ils sont menacés dans les zones d’agriculture intensive. Du fait de leur importance dans les réseaux trophiques, notamment comme ressources alimentaires pour un grand nombre d’espèces aviaires, ils font l’objet d’une attention croissante des écologistes et des gestionnaires des milieux dans le cadre d’études de conservation pour évaluer quantitativement leurs populations. L’objectif de cette étude est de décrire une technique d’échantillonnage et un plan d’échantillonnage destinés à estimer la densité de criquets dans les milieux prairiaux. Cette étude se base sur 7 années d’observations de terrain, menées sur un vaste site d’étude en plaine agricole intensive. Nous montrons que le biocénomètre d’1 m2 de base est une technique robuste vis-à-vis des conditions de température durant l’échantillonnage. L’étude établit pour l’ensemble des espèces et pour deux espèces particulières, Pezotettix giornae et Calliptamus italicus, la relation qui lie la variance et la moyenne des effectifs par m2. C’est grâce à cette relation qu’on peut établir les tailles d’échantillons qui permettent d’atteindre des objectifs de précision choisis pour les estimateurs de la densité. Nous montrons que la réalisation de 15 lancers aléatoirement par parcelle permet d’obtenir des estimations de la densité de criquets/m2 dont la précision, définie par l’intervalle de confiance, varie selon la densité de 50% pour les densités inférieures à 1/m2 à 30% pour les densités de 2 à 7/m2 et à 20% pour les densités supérieures à 7/m2.  相似文献   

18.
19.
The aim of the present study was to determine the bioactive compounds in four essential oils (EO’s) from Origanum heracleoticum, Origanum vulgare, Thymus vulgaris and Thymus serpyllum and to assess their antimicrobial and anti-biofilm activity against Salmonella Enteritidis. Strains were previously characterized depending on the expression of the extracellular matrix components cellulose and curli fimbriae as rdar (red, dry and rough) and bdar morphotype (brown, dry and rough). This study revealed that the EO’s and EOC’s (carvacrol and thymol) investigated showed inhibition of biofilm formation at sub-minimum inhibitory concentration. Comparing the efficacy of EO’s and EOC’s in the inhibition of biofilm formation between the strains with different morphotype (rdar and bdar) did not show a statistically significant difference. Results related to the effectiveness of EO’s and EOC’s (the essential oil components, carvacrol and thymol) on eradication of preformed 48?h old biofilms indicated that biofilm reduction occurred in a dose-dependent manner over time.  相似文献   

20.
The following problems are discussed: generalities; punctuation marks, conjunctions, and prepositions used in the citations of the authors’ names; citation of other persons; identification of the author(s) in complicated cases; determining the author’s surname or its equivalent; citation and abbreviation of the author’s surname.  相似文献   

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