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The Etruscan culture is documented in Etruria, Central Italy, from the 8th to the 1st century BC. For more than 2,000 years there has been disagreement on the Etruscans’ biological origins, whether local or in Anatolia. Genetic affinities with both Tuscan and Anatolian populations have been reported, but so far all attempts have failed to fit the Etruscans’ and modern populations in the same genealogy. We extracted and typed the hypervariable region of mitochondrial DNA of 14 individuals buried in two Etruscan necropoleis, analyzing them along with other Etruscan and Medieval samples, and 4,910 contemporary individuals from the Mediterranean basin. Comparing ancient (30 Etruscans, 27 Medieval individuals) and modern DNA sequences (370 Tuscans), with the results of millions of computer simulations, we show that the Etruscans can be considered ancestral, with a high degree of confidence, to the current inhabitants of Casentino and Volterra, but not to the general contemporary population of the former Etruscan homeland. By further considering two Anatolian samples (35 and 123 individuals) we could estimate that the genetic links between Tuscany and Anatolia date back to at least 5,000 years ago, strongly suggesting that the Etruscan culture developed locally, and not as an immediate consequence of immigration from the Eastern Mediterranean shores.  相似文献   

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The subcommissural organ (SCO) secretes glycoproteins into the cerebrospinal fluid (CSF) that aggregate and form Reissner's fiber (RF). The factors involved in this aggregation are not known. One factor may be the hydrodynamics of the CSF when flowing through the aqueduct. This hypothesis was tested by isografting rat SCO and xenografting bovine SCO into the lateral ventricle of rats. Xenografts were either fresh bovine SCO or explants cultured for 30 days before transplantation. The grafts were investigated by electron microscopy and immunocytochemistry using antibodies against RF glycoproteins, serotonin and the glucose transporter I. Maximal time of transplantation was 43 days for isografts and 14 days for xenografts. The isografts were not reinnervated but were revascularized; they secreted into the ventricle RF glycoproteins that became progressively packed into pre-RF and RF structures identical to those formed by the SCO in situ. RF was confined to the host ventricle and at its distal end the constituent proteins disassembled. Xenografts were neither reinnervated nor revascularized and secreted into the host ventricle a material that never formed an RF. These findings indicate that the CSF factor responsible for the formation of RF is species specific, and that this process does not depend on the hydrodynamics of the CSF. The blood vessels revascularizing the isografted SCO acquired the characteristics of the vessels irrigating the SCO in situ, namely, a tight endothelium displaying glucose transporter I, and a perivascular space containing long-spacing collagen, thus indicating that basal release of glycoproteins may also occur in the grafted SCO.  相似文献   

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Wielkopolska (western Poland) is a region, with good reason, called the main food base of Poland. All indices of agricultural production have always been there (since 19th century) much higher than elsewhere in the country (Ratajczak 1977/1978, Buszko 1984, Gorzelak 1989, Czyzewski et al. 1992; table 1). Such a situation had a beneficial effect on the amount of the income generated by a family of Wielkopolska and, thus, decided on its better financial status. Additionally, rural inhabitants of this region have always been characterised by a more advantageous educational structure in comparison with people of other Polish villages. Generally, it is easy to detect the relationship between the life standard, the level of education and family planning. The aim of this paper is to assess fertility of women from villages of Wielkopolska in the period of transformation of the political and economic system in Poland.  相似文献   

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The essay attempts to delineate how Maurice Merleau-Ponty’s phenomenology of perception can be applied to theories of sign processes, and how it reworks the framework of the phenomenalist conception of communication. His later philosophy involved a reformulation of subjectivity and a resolution of the subject/object dualism. My claim is that this non-reductionist theory of perception reveals a different view of nature as we experience it in an expressive and meaningful interaction. The perspective that another living being has and communicates entails a form of depth, the invisible dimension of the visible or audible. These two aspects of perception and dialogue are intertwined in a dialectic of presence and absence, so that sense arises in the perceptual field rather than in subjectivity. This, I argue, is the most fundamental result of his theory. The origination of meaning in the workings of the chiasm of visible and invisible in perception opens up an objective sense of intersubjective nature. The essay also deals with the role of the phenomenological reduction; a suspension of beliefs and existence claims in experience. The reduction enables us to take a step back and look more closely at our understanding of nature in light of the historical and cultural influence on our thinking.  相似文献   

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We present ataxonomic revision of the ‘manna lichens’ based on morphological, chemical, ecological and molecular data. A large number of herbarium specimens and fresh collections were examined. Phylogenetic analyses were performed using nuclear ribosomal (nrITS, nrLSU) and mitochondrial small subunit (mtSSU) sequences. Some notable phenotypic characters were plotted on the phylogenetic tree, and the analysis reveals that some of these characters are useful for genus and species level distinction of certain ‘manna lichens.’ Phylogeny of the Megasporaceae was revised using a combined data set of nrLSU and mtSSU and performing parsimony and Bayesian analyses. Five genera (Aspicilia, Circinaria, Lobothallia, Megaspora and Sagedia) are recognized. Further, the relationships of five presumably closely related genera of ‘manna lichens’, namely Agrestia (vagrant), Aspicilia (crustose) Circinaria (crustose), Chlorangium (vagrant) and Sphaerothallia (vagrant) with different growth forms were analysed. The analyses revealed that ‘manna lichens’ do not form a monophyletic group but occur in different clades within the genus Circinaria. The genera Agrestia, Chlorangium and Sphaerothallia are assigned as new synonyms under the genus Circinaria and no vagrant or erratic species remain in the genus Aspicilia. The analyses also show that five new erratic, vagrant and crustose species can be recognized. In this study two ‘manna lichens’, viz. Circinaria rostamii sp. nov. (Azerbaijan, Iran and Turkey), and Circinaria gyrosa sp. nov. (Armenia, Azerbaijan, Iran, Turkey, Turkmenistan and Spain) are described as new to science. Three potentially new species with crustose and erratic forms need additional study. Aspicilia fruticolosofoliacea is reduced to synonymy under C. alpicola, and a lectotype is designated for C. aspera. Thirteen new combinations in Circinaria are presented. The phenomenon of vagrancy is briefly discussed, and the biogeography of the ‘manna lichens’ is outlined. Illustrations, distribution maps, and an identification key to the species are provided.  相似文献   

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Pablo Jaramillo 《Ethnos》2013,78(4):464-489
This article analyses the co-occurrence of two concerns often expressed by indigenous leaders involved with reparations for victims of paramilitaries in Colombia. These concerns revolve around discomfort with the intense use of hegemonic ‘gender’ discourses in the context of the reparations, and a feeling that leaders' involvement in the latter brings about a betrayal of the family and of themselves. By engaging with the local category of eirruku (flesh), I argue that ways of engaging women in reparations entail the commoditisation of caring relationships. This article, based on 13 months of fieldwork with an indigenous organisation and the communities integrated into it between 2007 and 2008, contributes to the understanding of the articulation of gender and ethnic/racial identification in the context of contemporary forms of governance of indigenous peoples, while delving into ‘carnality’ as a concept to understand gendered forms of reproduction, reparation and selfhood.  相似文献   

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Robin Nunn has argued that we should stop using the terms ‘placebo’ and ‘placebo effect’. I argue in support of Nunn’s position by considering the logic of why we perform placebo comparisons. Like all comparisons, placebo comparison is just a case of comparing one thing with another, but it is a mistake, I argue, to think of placebo comparison as a case where something is compared to ‘a placebo’. Rather, placebo comparison should be understood as a situation which sets-up the treatment and control groups in a particular way; not as a case involving objects or procedures called ‘placebos’ employed in order to control for ‘placebo effects’.  相似文献   

10.
The zooplankton composition is studied in the thermokarst, glacial and meteorite lakes, channels, former riverbeds, and hollows in the basin of Anadyr’. We found 174 taxa: 78, Rotatoria, 55, Cladocera, and 41, Copepoda. The most diverse is the lake fauna: 51 taxa of Rotatoria, 48, Cladocera, and 37, Copepoda. The thermokarst Lake Maiorskoe hosts 68 taxa: 31, Rotatoria, 14, Cladocera, and 23, Copepoda, wheras the cold ultraoligotrophic Lake El’gygytgyn features only one species of Cyclop of the group scutifer Cyclops neymanae Strel., and Rotatoria and Cladocera are present as allochtonous forms. The Copepoda illustrate the relations of the Anadyr’ fauna with those of Europe, North America, and Japan.  相似文献   

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Objective

We estimated the extent to which Canadian expectant parents would seek medical care in a febrile neonate (age 30 days or less). We also evaluated expectant parents’ knowledge of signs and symptoms of fever in a neonate, and explored the actions Canadian expectant parents would take to optimize the health of their child.

Methods

We conducted a cross-sectional survey of a sample of expectant parents from a large urban center in Canada. We recruited participants from waiting rooms in an obstetrical ultrasound clinic located in an urban tertiary care hospital in Montreal, Canada. We asked participants nine questions about fever in neonates including if, and how, they would seek care for their neonate if they suspected he/she were febrile.

Results

Among the 355 respondents, (response rate 87%) we found that 75% of parents reported that they would take their febrile neonate for immediate medical assessment, with nearly one fifth of the sample reporting that they would not seek medical care. We found no significant associations between the choice to seek medical care and expectant parents socio-demographic characteristics.

Conclusions

Despite universal access to high quality health care in Canada, our study highlights concerning gaps in the knowledge of the care of the febrile infant in one fifth of expectant parents. Physicians and health providers should strive to provide early education to expectant parents about how to recognize signs of fever in the neonate and how best to seek medical care. This may improve neonatal health outcomes in Canada.  相似文献   

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The lambeosaurine Tsintaosaurus spinorhinus has traditionally been reconstructed with an elevated, hollow, spike-like crest composed entirely of the nasal bones, although this has been disputed. Here, we provide a new reconstruction of the skull of this species based on reexamination and reinterpretation of the morphology and articular relationships of the type and Paratype skulls and a fragmentary crest. We confirm the presence of a supracranial crest composed of the elevated nasal bones, but also including the premaxillae. We hypothesize that the crest is a tall, lobate, hollow structure that projects dorsally and slightly caudally a distance greater than the height of the skull along the quadrate. In our reconstruction, the nasal passage passes through the crest, but enters the skull rostral to the tubular process of the nasals, not through it. Tsintaosaurus spinorhinus is rediagnosed on the basis of a suite of cranial autapomorphies including a circumnarial fossa subdivided into three accessory fossae, prefrontal with ascending rostral process and lateral flange, nasals fused sagittally to form elongate tubular process that rises dorsally from skull roof, each nasal being expanded rostrocaudally into a rhomboid distal process, and medial processes of premaxillae at the summit of the cranial crest inserted between rhomboid processes of nasals. Tsintaosaurus spinorhinus lacks characters that are present in more derived lambeosaurines (parasaurolophins and lambeosaurins), such as rotation of the caudal margin of the crest to an acute angle with the skull roof, lateral processes of the nasals that enclose part of the intracranial cavity and participate in the formation of the walls of the common median chamber, and a smooth narial fossa lacking ridges and accessory fossae. We hypothesize that ancestrally the rostrum of lambeosaurines may have been more similar to that in Saurolophinae, and became subsequently reduced in complexity during evolution of the group.  相似文献   

14.
This study provides a critical historical review and analysis of the variety of human expressions which have been erroneously labeled under the grandiose category mass hysteria. It is argued that Western science reductionist approaches to the classification of mass hysteria treat it as an entity to be discovered transculturally, and in their self-fulfilling search for universals systematically exclude what does not fit within the autonomous parameters of its Western-biased culture model, exemplifying what Kleinman (1977) terms a category fallacy. As a result of objectivist methodologies, the etiology of actions labeled as mass hysteria is typically viewed as deviant, irrational or abnormal behavior resulting from a malfunctioning proper social order. However, what constitutes the correct social order is a function of a researcher's historical sociocultural and/or scientific milieu. This study reviews the problem, advocating Geertz's (1973) culturally relativistic approach to understanding various cross-cultural behavior that is sensitive to and tolerant of the unique context and milieu of participants. Mass or epidemic hysteria is viewed as an invention of Western psychiatry and should be abandoned and replaced with the term collective exaggerated emotions. Instead of attempting to discover a neatly packaged, unitary external disease entity, the focus of a meaning-oriented approach emphasizes the deciphering of foreign realities, semantic networks and symbol systems.  相似文献   

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Wedekind C  Evanno G  Urbach D  Jacob A  Müller R 《Genetica》2008,132(2):199-208
Some models of sexual selection predict that individuals vary in their genetic quality and reveal some of this variation in their secondary sexual characteristics. Alpine whitefish (Coregonus sp.) develop breeding tubercles shortly before their spawning season. These tubercles are epidermal structures that are distributed regularly along the body sides of both males and females. There is still much unexplained variation in the size of breeding tubercles within both sexes and with much overlap between the sexes. It has been suggested that breeding tubercles function to maintain body contact between the mating partners during spawning, act as weapons for defence of spawning territories, or are sexual signals that reveal aspects of genetic quality. We took two samples of whitefish from their spawning place, one at the beginning and one around the peak of spawning season. We found that females have on average smaller breeding tubercles than males, and that tubercle size partly reveals the stage of gonad maturation. Two independent full-factorial breeding experiments revealed that embryo mortality was significantly influenced by male and female effects. This finding demonstrates that the males differed in their genetic quality (because offspring get nothing but genes from their fathers). Tubercle size was negatively linked to some aspects of embryo mortality in the first breeding experiment but not significantly so in the second. This lack of consistency adds to inconsistent results that were reported before and suggests that (i) some aspects of genetic quality are not revealed in breeding tubercles while others are, or (ii) individuals vary in their signaling strategies and the information content of breeding tubercles is not always reliable. Moreover, the fact that female whitefish have breeding tubercles of significant size while males seem to have few reasons to be choosy suggests that the tubercles might also serve some functions that are not linked to sexual signaling.  相似文献   

18.
Disbalance of zinc (Zn2+) and copper (Cu2+) ions in the central nervous system is involved in the pathogenesis of numerous neurodegenerative disorders such as multisystem atrophy, amyotrophic lateral sclerosis, Creutzfeldt-Jakob disease, Wilson-Konovalov disease, Alzheimer’s disease, and Parkinson’s disease. Among these, Alzheimer’s disease (AD) and Parkinson’s disease (PD) are the most frequent age-related neurodegenerative pathologies with disorders in Zn2+ and Cu2+ homeostasis playing a pivotal role in the mechanisms of pathogenesis. In this review we generalized and systematized current literature data concerning this problem. The interactions of Zn2+ and Cu2+ with amyloid precursor protein (APP), β-amyloid (Abeta), tau-protein, metallothioneins, and GSK3β are considered, as well as the role of these interactions in the generation of free radicals in AD and PD. Analysis of the literature suggests that the main factors of AD and PD pathogenesis (oxidative stress, structural disorders and aggregation of proteins, mitochondrial dysfunction, energy deficiency) that initiate a cascade of events resulting finally in the dysfunction of neuronal networks are mediated by the disbalance of Zn2+ and Cu2+.  相似文献   

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ABSTRACT

This essay responds to David Roediger's Seizing Freedom: Slave Emancipation and Liberty for All. After a brief examination of the central themes of the book, I turn to the author's emphasis upon political agency. I argue that this emphasis is necessary, given the political and scholarly aims of the book. At the same time, I suggest that the agency depicted in Seizing Freedom was simultaneously constrained by the cultural, political, and social forces discussed in Roediger's earlier companion volume, The Wages of Whiteness. I end the essay with a short discussion of the labour leader William Sylvis that attempts to synthesize insights from Seizing Freedom and The Wages of Whiteness in order to explain the ‘strange blindness’ that led white labour to systematically ignore and repress the activity of black workers.  相似文献   

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