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1.
In spite of the importance of auditory ossicles in anthropological studies, very little attention has been paid to these bones, which are only rarely recovered in archaeological excavations and in osteological collections. In this paper, we attempt to review some studies that started in the 1960 from when we first collected and prepared ossicles from the early Egyptian osteological collection of Giovanni Marro in Turin (Italy). We attempt to delineate the potential of ear bones in the study of man. In a few cases, archaeological ossicles were discussed in connection with some forms of pathology. Other studies examined the phylogeny of primates based on auditory ossicles. The function of the ossicles is to transmit sound waves to the cochlear endolymph. The energy transmitted through the ossicles is conserved by the action of two levers, which convert the relatively wide and low-energy movements of the hammer into smaller high-energy movements of the stirrup. It is a matter of argument whether the different proportions of the ossicles may imply variations in auditory perception in primates, including man. While the hammer of modern humans and that of the great apes show similar absolute sizes, nevertheless, the ape manubrium is appreciably greater than that of man. This difference, combined with stirrup proportions, causes a strong “low-gear” effect in apes and, as a consequence, probably a different auditory acuity. Although only a few fossil Neanderthal auditory ossicles are known, it may be, nevertheless, of interest studying the ossicles from the viewpoint of vibration transfer impedance function. The methodology may also be appropriate to study the few Australopithecine ossicles that are known. It is a matter of question whether the ossicles may have a meaning in distinguishing human populations; nevertheless, at least a case of clear distinction between human population has been achieved as in the case of Antinoe Roman–Egyptians. 相似文献
2.
Richard Huxtable 《Journal of bioethical inquiry》2009,6(3):327-336
Amongst the latest, and ever-changing, pathways of death and dying, “suicide tourism” presents distinctive ethical, legal
and practical challenges. The international media report that citizens from across the world are travelling or seeking to
travel to Switzerland, where they hope to be helped to die. In this paper I aim to explore three issues associated with this
phenomenon: how to define “suicide tourism” and “assisted suicide tourism”, in which the suicidal individual is helped to
travel to take up the option of assisted dying; the (il)legality of assisted suicide tourism, particularly in the English
legal system where there has been considerable recent activity; and the ethical dimensions of the practice. I will suggest
that the suicide tourist—and specifically any accomplice thereof—risks springing a legal trap, but that there is good reason
to prefer a more tolerant policy, premised on compromise and ethical pluralism. 相似文献
3.
Historical evidence suggests that the Christian Coptic population of Antinoe necropolis, probable descendants of Dynastic
Egyptians, may reflect admixture from Greek and Roman populations. Within the anthropological surveys on Antinoe skeletal
remains (A.D. 300–600), a sample of auditory ossicles was compared with a Dynastic Egyptian sample (“G. Marro” osteological
collection), from Asiut and Gebelen Univariate and multivariate statistical analyses were applied, to this end.
The auditory ossicles are generally larger in the Coptic group; in both groups shape measurements have a high variability,
while size measurements are relatively invariable. Univariate variances are homogeneous but the means are significantly different.
This suggests genetic changes, but identical patterns of variation.
The stepwise discriminant functions analysis and the Generalized Distance, suggesting a biological heterogeneity in the Antinoe
sample in spite of some similarity of the two groups, tend to support this.
Further analyses of the auditory ossicles in Greek and Roman populations are however needed to confirm the gene flow hypothesis
in the Antinoe population, suggested by historical data. 相似文献
4.
C. Dall’Asta S. Sforza A. Moseriti G. Galaverna A. Dossena R. Marchelli 《Mycotoxin Research》2005,21(4):218-223
Zearalenone is a mycotoxin mainly produced by severalFusarium species, which are known to colonize grains in temperate climates. The purpose of the study is to provide a reliable isotope
dilution method for the quantification of this mycotoxin. A derivative of the analyte to be used as standard is obtained by
reaction with acetic anhydride, which is available in two pure isotopic forms, a protonated (“light”) and a hexadeuterated
(“heavy”). The derivatized standards are added to the matrix split intwo parts. Then, the derivatization procedure is repeated
on both matrices derivatizing the part containing the “heavy” labelled standard with the “light” acetic anhydride and the
part containing the “light” labelled standard with the “heavy” acetic anhydride. Both extracted mixtures are analyzed by LC/MS,
monitoring the “light” and the “heavy” labelled analytes and using the former as standard for the latter in one case and viceversa
in the other case. The method allowed to obtain very good results, without the need of IAC purification.
Presented at the 27th Mykotoxin-Workshop, Dortmund, Germany, June 13–15, 2005.
Financial support: The Italian Ministry of Health 相似文献
5.
Victoria N. Alexander 《Biosemiotics》2009,2(1):77-100
Hackles have been raised in biosemiotic circles by T. L. Short’s assertion that semiosis, as defined by Peirce, entails “acting
for purposes” and therefore is not found below the level of the organism (2007a:174–177). This paper examines Short’s teleology and theory of purposeful behavior and offers a remedy to the disagreement.
Remediation becomes possible when the issue is reframed in the terms of the complexity sciences, which allows intentionality
to be understood as the interplay between local and global aspects of a system within a system. What is called “acting for
purposes” is not itself a type of behavior so much as a relationship between a dynamic system that “exists for a purpose”
and its microprocesses that “serve purposes.” The “intentional object” of philosophy is recast here as the holistic self-organized
dynamics of a system, which exists for the purpose of self-maintenance, and that constrains the parts’ behaviors, which serve
the purpose of forming the system. (A “system” can be any emergent, e.g. an abiotic form, an adapted species, a self, a conditioned response, thought, or a set of ideas.) The self-organized whole,
which is represented to the parts in their own constrained behaviors, assumes the guiding function so long attributed to the
mysterious “intentional object.” If emergent self-causation is not disallowed, creative originality, as well as directionality, becomes part of the definition of purposeful behavior. Thus, key tools used here, required for understanding emergence, come
from poetics rather than semoitics. In the microprocesses of self-organization, I find what I call “accidental” indices and
icons — which are poetic in the sense that they involve mere metonymic contiguity and metaphoric similarity — and which are
preferentially selected under constrained conditions allowing radically new connections to habituate into an “intentional”
self-organized system that, not coincidentally, has some of the emergent characteristics of a conventional symbolic system.
相似文献
Victoria N. AlexanderEmail: |
6.
T. E. Hetherington E. D. Lindquist 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1999,184(4):395-401
The mechanisms of hearing in the fire-bellied toad Bombina orientalis, an “earless” species of amphibian that lacks a standard tympanic middle ear, were studied using laser Doppler vibrometric
and neurophysiological techniques. Laser vibrometry demonstrated that the anterolateral body wall overlying the lung is much
more responsive to sound than the lateral head surface overlying the inner ear. Covering the lateral body wall with silicone
grease dramatically decreased auditory midbrain sensitivity at all frequencies examined, elevating thresholds by 20–25 dB.
Filling the lungs with oxygenated saline produced similar decrements in hearing sensitivity, and both manipulations strongly
suggest that the lung is the primary route of sound reception in this species. The precise route of transfer of sound energy
from the body wall and lungs to the inner ear remains unclear. The lung-based hearing system of “earless” fire-bellied toads
may represent the retention of the first auditory mechanism used by early tetrapod vertebrates for detection of airborne sound.
Accepted: 10 December 1998 相似文献
7.
Anatol Rapoport 《Bulletin of mathematical biology》1961,23(4):321-335
As a “base line” of memorization performance, the behavior of a “perfect learner” is considered. He is characterized by a
perfect memory and by the ability to choose the best search procedure in problems where the correct response from a given
repertoire is to be found to each of several stimuli under the condition of “right” and “wroing” promptings by the experimenter.
Expected learning curves are derived for the case of disjoint response repertoires associated with the stimuli under cyclic
and random presentation of the stimuli and for the case of a single response repertoire (a one-to-one matching problem) under
cyclic presentation. 相似文献
8.
9.
Source-sink landscape theory and its ecological significance 总被引:2,自引:0,他引:2
Exploring the relationships between landscape pattern and ecological processes is the key topic of landscape ecology, for
which, a large number of indices as well as landscape pattern analysis model were developed. However, one problem faced by
landscape ecologists is that it is hard to link the landscape indices with a specific ecological process. Linking landscape
pattern and ecological processes has become a challenge for landscape ecologists. “Source” and “sink” are common concepts
used in air pollution research, by which the movement direction and pattern of different pollutants in air can be clearly
identified. In fact, for any ecological process, the research can be considered as a balance between the source and the sink
in space. Thus, the concepts of “source” and “sink” could be implemented to the research of landscape pattern and ecological
processes. In this paper, a theory of sourcesink landscape was proposed, which include: (1) In the research of landscape pattern
and ecological process, all landscape types can be divided into two groups, “source” landscape and “sink” landscape. “Source”
landscape contributes positively to the ecological process, while “sink” landscape is unhelpful to the ecological process.
(2) Both landscapes are recognized with regard to the specific ecological process. “Source” landscape in a target ecological
process may change into a “sink” landscape as in another ecological process. Therefore, the ecological process should be determined
before “source” or “sink” landscape were defined. (3) The key point to distinguish “source” landscape from “sink” landscape
is to quantify the effect of landscape on ecological process. The positive effect is made by “source” landscape, and the negative
effect by “sink” landscape. (4) For the same ecological process, the contribution of “source” landscapes may vary, and it
is the same to the “sink” landscapes. It is required to determine the weight of each landscape type on ecological processes.
(5) The sourcesink principle can be applied to non-point source pollution control, biologic diversity protection, urban heat
island effect mitigation, etc. However, the landscape evaluation models need to be calibrated respectively, because different
ecological processes correspond with different source-sink landscapes and evaluation models for the different study areas.
This theory is helpful to further study landscape pattern and ecological process, and offers a basis for new landscape index
design.
__________
Translated from Acta Ecologica Sinica, 2006, 26(5): 1444–1449 [译自: 生态学报] 相似文献
10.
We report a phylogenetic analysis of “core” Malvales (Tiliaceae, Sterculiaceae, Bombacaceae, and Malvaceae) based on morphological,
anatomical, palynological, and chemical features. The results of the analyses lead to the conclusion that Tiliaceae, Sterculiaceae,
and Bombacaceae, as variously delimited, are paraphyletic; only the Malvaceae are likely monophyletic. The genera of “core”
Malvales form a well-defined clade. Genera of “Tiliaceae” constitute the basal complex within “core” Malvales. The “Sterculiaceae”
(most genera)+ “Bombacaceae” + Malvaceae form a clade on the basis of a monadelphous androecium; “Bombacaceae”+ Malvaceae
also form a clade, which is diagnosable on the basis of monoloculate anthers. It is clear that the traditional classification,
with its arbitrarily delimited evolutionary grades, is unsatisfactory, especially if one seeks to reflect phylogeny accurately.
Thus, Malvaceae is redefined to refer to the most recent common ancestor of plants previously considered to be “Tiliaceae,”
“Sterculiaceae,” “Bombacaceae,” and Malvaceae, and all of the descendants of that ancestor. This broadly circumscribed Malvaceae
can be diagnosed by several presumed synapomorphies, but we draw special attention to the unusual floral nectaries that are
composed of densely packed, multicellular, glandular hairs on the sepals (or less commonly on the petals or androgynophore). 相似文献
11.
Promoters of the PhyloCode have mounted an intensive and deceptive publicity campaign. At the centerpiece of this campaign
have been slogans such as that the Linnaean System will “goof you up,” that the PhyloCode is the “greatest thing since sliced
bread,” and that systematists are “afraid” to propose new names because of “downstream consequences.” Aside from such subscientific
spin and sloganeering, proponents of the PhyloCode have offered nothing real to back up claims of greater stability for their
new system. They have also misled many into believing that the PhyloCode is the only truly phylogenetic system. The confusion
that has been fostered involves several discrete arguments, concerning: a new “method” of “designating” names, rank-free taxonomy,
uninomial nomenclature, and issues of priority. Claims that the PhyloCode produces a more stable nomenclature are false, as
shown with the example of “paleoherbs.” A rank-free system of naming requires an annotated reference tree for even the simplest
exchanges of information. This would be confusing at best and would cripple our ability to teach, learn, and use taxonomic
names in the field or in publications. We would be confronted by a mass of polynomial names, tied together only by a tree
graphic, with no agreed name (except a uninomial, conveying no hierarchy) to use for any particular species. The separate
issue of stability in reference to rules of priority and rank can be easily addressed within the current codes, by implementation
of some simple changes, as we will propose in this article. Thus there is no need to “scrap” the current Linnaean codes for
a poorly reasoned, logically inconsistent, and fatally flawed new code that will only bring chaos. 相似文献
12.
Protein evolution is not a random process. Views which attribute randomness to molecular change, deleterious nature to single-gene
mutations, insufficient geological time, or population size for molecular improvements to occur, or invoke “design creationism”
to account for complexity in molecular structures and biological processes, are unfounded. Scientific evidence suggests that
natural selection tinkers with molecular improvements by retaining adaptive peptide sequence. We used slot-machine probabilities
and ion channels to show biological directionality on molecular change. Because ion channels reside in the lipid bilayer of
cell membranes, their residue location must be in balance with the membrane’s hydrophobic/philic nature; a selective “pore”
for ion passage is located within the hydrophobic region. We contrasted the random generation of DNA sequence for KcsA, a
bacterial two-transmembrane-domain (2TM) potassium channel, from Streptomyces lividans, with an under-selection scenario, the “jackprot,” which predicted much faster evolution than by chance. We wrote a computer
program in JAVA APPLET version 1.0 and designed an online interface, The Jackprot Simulation
, to model a numerical interaction between mutation rate and natural selection during a scenario of polypeptide evolution.
Winning the “jackprot,” or highest-fitness complete-peptide sequence, required cumulative smaller “wins” (rewarded by selection)
at the first, second, and third positions in each of the 161 KcsA codons (“jackdons” that led to “jackacids” that led to the
“jackprot”). The “jackprot” is a didactic tool to demonstrate how mutation rate coupled with natural selection suffices to
explain the evolution of specialized proteins, such as the complex six-transmembrane (6TM) domain potassium, sodium, or calcium
channels. Ancestral DNA sequences coding for 2TM-like proteins underwent nucleotide “edition” and gene duplications to generate
the 6TMs. Ion channels are essential to the physiology of neurons, ganglia, and brains, and were crucial to the evolutionary
advent of consciousness. The Jackprot Simulation illustrates in a computer model that evolution is not and cannot be a random
process as conceived by design creationists. 相似文献
13.
Kenichi Ohara Momoko Hotta Daisuke Takahashi Takashi Asahida Hitoshi Ida Tetsuya Umino 《Ichthyological Research》2009,56(4):373-379
The genetic diversity and relationship among four morphotypes of Rhinogobius sp. OR, Gobiidae (“Tōshoku,” “Shinjiko,” “Gi-tōshoku,” and “Shimahire”) were investigated with seven microsatellite DNA loci,
and amphidromy of these morphotypes was verified by strontium (Sr) and calcium (Ca) deposition in the otolith. Samples of
“Tōshoku,” “Shinjiko,” “Gi-tōshoku,” and “Shimahire” were collected from, respectively, three, three, two, and four locations
in Japan. Microsatellite analysis detected high genetic diversity (based on the number of alleles, allelic richness, and average
observed heterozygosity) in the “Tōshoku” and “Shinjiko” morphotypes relative to the “Shimahire” morphotype; the “Gi-tōshoku”
morphotype had an intermediate level of variation. Almost all pairwise F
ST values were significantly different from zero (P < 0.001), except between two populations of “Tōshoku.” Clear genetic independence was observed between the “Shinjiko” and
“Shimahire” morphotypes in the Maruyama River. A principle component analysis based on microsatellite data indicated that
the “Tōshoku,” “Shinjiko,” and “Gi-tōshoku” morphotypes were genetically similar. Furthermore, the three populations of “Tōshoku”
were closely related each other, and two of those collected from the Lake Biwa system were a single population. There was,
however, a high degree of genetic differentiation between “Shimahire” and the other morphotypes; moreover, there was high
genetic divergence among four populations of the “Shimahire” morphotype. Amphidromous migratory histories were indicated by
Sr:Ca ratios in two of three populations of the “Shinjiko” morphotype and in one of two “Gi-tōshoku” morphotypes, whereas
all populations of the “Shimahire” morphotype were freshwater residents. The large genetic divergence and low genetic diversity
in “Shimahire” are likely related to migration history. 相似文献
14.
Maree Porter Ian H. Kerridge Christopher F. C. Jordens 《Journal of bioethical inquiry》2012,9(1):41-47
Umbilical cord blood banking is one of many biomedical innovations that confront pregnant women with new choices about what
they should do to secure their own and their child’s best interests. Many mothers can now choose to donate their baby’s umbilical
cord blood (UCB) to a public cord blood bank or pay to store it in a private cord blood bank. Donation to a public bank is
widely regarded as an altruistic act of civic responsibility. Paying to store UCB may be regarded as a “unique opportunity”
to provide “insurance” for the child’s future. This paper reports findings from a survey of Australian women that investigated
the decision to either donate or store UCB. We conclude that mothers are faced with competing discourses that force them to
choose between being a “good mother” and fulfilling their role as a “good citizen.” We discuss this finding with reference
to the concept of value pluralism. 相似文献
15.
V. V. Shakhparonov 《Biology Bulletin》2011,38(5):528-532
The behavior of frogs from southern areas with an arid climate released during the reproductive period between their “home”
pond and a less distant river is shown to be independent of weather conditions. The experiments were performed on frogs living
near the village of Dosang, Astrakhan oblast. The frogs were released 60 to 150 m from their “home” breeding waterbody and
60 to 80 m from an “alien” waterbody. Four experiments were performed on 27 individuals. The movements of the frogs were traced
by the method of “tracking by a thread.” The results revealed no preference in the frogs to return to their own breeding ponds,
rather than to the nearby river. This behavior is peculiar to frogs of southern populations. 相似文献
16.
Approximately 1 500 angiosperm species, in previous papers, have been sampled for the assessment of the amino acids (a. a.)
in their nectar. We reaffirm that the findings provide statistically significant data linking differences in the concentration
with pollinator type. Flowers that are pollinated by animals that have alternative sources of protein-building a. a.’s show
lower a. a. concentration than those that are not. There is a tendency for woody plant nectar a. a.’s to be less concentrated
than those of herbaceous plants, but there can be “phylogenetic constraints” which may reduce the correlations of a. a. concentration
with pollinator type and with life form. The individual a. a.’s form complements which are qualitatively extremely constant
within species. Proline is a normal constituent of many nectars and does not necessarily indicate contamination of the nectar
by pollen. Criticism of our findings byGottsberger & al. (1984) is answered by reference to our previous publications and those of other workers, and to the presentation of
data from California native species, not published previously. All previous postulates are borne out by these new data with
the exception of positive correlations of a. a. concentration with “primitive” and “advanced” floral characteristics taken
one at a time, which appear to be inconsistent and are affected strongly by the nature of the family in which they occur.
Summary data are provided for families and genera which indicate that high or low a. a. concentration can typify certain families
and genera of both relatively “primitive” and relatively “advanced” nature. Needs for future research on an ecosystem basis
are quoted. 相似文献
17.
Microtubules (MT) are composed of 13 protofilaments, each of which is a series of two-state tubulin dimers. In the MT wall,
these dimers can be pictured as “lattice” sites similar to crystal lattices. Based on the pseudo-spin model, two different
location states of the mobile electron in each dimer are proposed. Accordingly, the MT wall is described as an anisotropic
two-dimensional (2D) pseudo-spin system considering a periodic triangular “lattice”. Because three different “spin-spin” interactions
in each cell exist periodically in the whole MT wall, the system may be shown to be an array of three types of two-pseudo-spin-state
dimers. For the above-mentioned condition, the processing of quantum information is presented by using the scheme developed
by Lloyd. 相似文献
18.
Through the use of principal components analysis of the correlation matrix between excentricity quotients of intra- and inter-individual
transitions between pairs of the 22 most frequent behaviour elements of male and female gelada baboons observed in captivity,
the total variance could be described in terms of a low number of causal factors. In intra-individual sequences the five factors
requested of the analysis explain 74 per cent of the total variance. The following intra-individual groupings were found:
(I) “autostimulation”, (II) “intensive social” versus “groom”, (III) “male sexual”, (IV) “attack” versus “sexual presentation”,
and (V) “greeting” versus “threat”. In inter-individual transitions, the five factors explain 68 per cent of the variance.
The following communicative sets were found: (1) “female-sexual releasing”, (2) “greeting and approaching releasing” versus
“groom releasing”, (3) “austostimulation releasing” versus “male-sexual releasing”, (4) “fight releasing”, and (5) “conflict”.
Mimetic induction of same acts or acts within one particular intra-individual set was frequent. 相似文献
19.
Morris H. Baslow 《Biosemiotics》2011,4(1):39-53
The human brain is a complex organ made up of neurons and several other cell types, and whose role is processing information
for use in elicitation of behaviors. To accomplish this, the brain requires large amounts of energy, and this energy is obtained
by the oxidation of glucose (Glc). However, the question of how the oxidation of Glc by individual neurons in brain results
in their collective ability to rapidly generate feats of cognition that allow them to recognize the nature of the universe
in which they live and to communicate this information remains unclear. In this article, insights into this process are provided
by first considering the brain’ s homeostatic “operating system” for supply of energy to stimulated neurons, and how this
system defines the basic unit of brain “structure”. This is followed by consideration of the brain’s “two-cell” neuronal communication
mechanism which defines the basic unit of brain “function”. Finally, an analysis of the nature of frequency-encoded “neuronal
languages” that enable ensembles of neurons to translate energy derived from the oxidation of Glc into a collective “mind”,
the aggregate of all brain processes including those involving perception, thought, insight, foresight, imagination and behavior. 相似文献
20.
Willson SJ 《Bulletin of mathematical biology》2007,69(8):2561-2590
Suppose G is a phylogenetic network given as a rooted acyclic directed graph. Let X be a subset of the vertex set containing the root, all leaves, and all vertices of outdegree 1. A vertex is “regular” if
it has a unique parent, and “hybrid” if it has two parents. Consider the case where each gene is binary. Assume an idealized
system of inheritance in which no homoplasies occur at regular vertices, but homoplasies can occur at hybrid vertices. Under
our model, the distances between taxa are shown to be described using a system of numbers called “originating weights” and
“homoplasy weights.” Assume that the distances are known between all members of X. Sufficient conditions are given such that the graph G and all the originating and homoplasy weights can be reconstructed from the given distances. 相似文献