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1.
The structure of the Dutch Relational Archaeobotanical Database (RADAR) is presented. RADAR is a rather compact archaeobotanical database that is controlled centrally, but can be distributed to individual scientists. For this reason RADAR contains only the most important archaeobotanical data. For detailed archaeological, botanical and regional palaeoenvironmental information, links can be established with the national archaeological database (ARCHIS), the national botanical database (BBR) and the European Pollen Database (EPD). The software used for manipulation of the database is PARADOX for reasons of its highly visible nature, its control facilities for data entry and the ease of importing and exporting data from and to many other programs. The potential of the database is demonstrated with query examples. 相似文献
2.
The region of Asturias, northwest Spain, is highly unusual in that a cereal crop (spelt wheat) is cultivated on a garden
scale using horticultural methods. A floristic survey was made of the weeds in 65 spelt plots in this region. The ecological
attributes of the weed species were then measured and compared to an earlier study of the functional characteristics of weeds
associated with pulse crops on the Greek island of Evvia. In this earlier study, it was possible to distinguish between plots
cultivated intensively on a garden-scale and plots cultivated extensively in fields, on the basis of a suite of functional
attributes of the weed species. The cereal plots from Asturias were correctly identified as gardens on the basis of the same
suite of attributes. The Asturias plots were also compared to weed associations from autumn- and spring-sown crops in Germany,
using a different suite of attributes, and were classified either as autumn-sown or ambiguously. This is consistent with the
sowing time in Asturias, which is spread over late autumn to winter. These results demonstrate that the suites of functional
attributes identified to distinguish intensive and extensive cultivation, and to recognise sowing time, can be applied in
another geographical area and to another crop type. This paves the way for the application of these attributes to the identification
of past agricultural practices from archaeological weed assemblages.
Received September 12, 2001 / Accepted December 12, 2002 相似文献
3.
The oldes Neolithic crab apple ( Malus sylvestris L.) remains have been found in the Gwoździec 2 site (southeast Poland), archaeologically dated to the earliest part of the
Linear Pottery Culture. There is also another find of apple pips from Poland (Dąbki site) identified as Malus sylvestris L. and after a long discussion archaeologically dated to the proto-Neolithic period. Wild apple fruits were gathered and
dried for storage, as was the case in several other sites in Europe.
Received October 10, 2000 / Accepted December 13, 2000 相似文献
4.
The Neolithic site at Hidden Valley, Farafra Oasis, Egypt (6028±150 – 5163±374 cal B. C.) on the shores of a playa (dry lake
basin in the desert), yielded a large quantity of carbonized plant remains from post-holes, hearths, querns and a corridor.
The plant remains could have become carbonised during food preparation, or when fuel included seeds. Rich and diverse floras
were retrieved from 40 soil samples, in all 534 seeds, grains, spikelets, culm fragments and leaflet fragments which were
attributed to 30 taxa in the flora of Egypt. Wild grasses from almost all samples represent 83% of the plant remains. Quantitative
correlation between plants remains and archaeological contexts is discussed. The highest density of plant remains was recorded
from pot-holes (in which pots were stood), while sediments recovered near querns show the lowest. The economy of the site
was apparently based mainly on herding associated with the gathering of grasses which suggests that the climate at Farafra
during the middle Holocene (6077–4511 cal B. C.) was wetter than today's, with winter and summer rainfall. A reconstruction
of the vegetation around the site comprises reed plant cover, aquatic and wetland plants and desert savanna.
Received March 8, 2001 / Accepted June, 2001 相似文献
5.
Archaeobotanical evidence is presented for early agriculture at southwestern Ljubljansko barje (Ljubljana Moor), Slovenia.
Archaeobotanical finds from the Eneolithic site at Hočevarica, and pollen records from an archaeological profile and from
a nearby core were analysed. Numerous charred grains of cultivated cereals together with fossil seeds of Chenopodium sp. demonstrate that during the occupation of the settlement at Hočevarica, agriculture was well established. The majority
of identified grains were of Hordeum vulgare (cultivated barley) and the rest were Triticum monococcum and T. turgidum ssp. dicoccum (cultivated wheats). Large amounts of cereal pollen and pollen of Chenopodiaceae also suggest strong human impact on the
surrounding vegetation and landscape. Pollen and archaeobotanical data from Hočevarica show a large consistency in timing
of the appearance of agriculture. In the pollen record from the core at Hočevarica a significant increase (up to 40%) in cereal
pollen was detected at 4881 ± 50 B.P. (3770-3630 cal B.C.). Charred cereal grains were dated to 4800 ± 40 B.P. (3650-3520
cal B.C.). The grains of cultivated cereals from Hočevarica represent the oldest archaeobotanical evidence for agriculture
in central Slovenia.
Received February 18, 2002 / Accepted October 21, 2002 相似文献
6.
The results produced by charcoal analysis are used in conjuction with pollen evidence, geomorphological data and ecological
analogues, in order to reconstruct ancient woodland vegetation in the Konya Basin and its surroundings during the Neolithic.
Emphasis is placed on the structure, diversity and seasonal habit of different vegetation types, as well as their potential
response to natural and/or anthropogenic disturbance. It is argued that such an approach to vegetation reconstruction enables
better insights into palaeoenvironments as experienced by human groups in the past, and thus offers fruitful avenues for investigating
the relationship of human societies with the natural environment.
Received December 2, 1999 / Accepted June 9, 2000 相似文献
7.
Analysis of charred plant macro-remains, including wood charcoals, cereals, seeds, tubers and fruits from the Neolithic site
of ?atalh?yük has indicated complex patterns of plant resource use and exploitation in the Konya plain during the early Holocene.
Evidence presented in this paper shows that settlement location was not dictated by proximity to high quality arable land
and direct access to arboreal resources (firewood, timber, fruit producing species). A summary of the patterns observed in
sample composition and species representation is outlined here together with preliminary interpretations of these results
within their broader regional context.
Received September 4, 2001 / Accepted April 9, 2002 相似文献
8.
Neolithic settlements in the Kujawy region of central Poland are represented by seven archaeological sites which have botanical
material archaeologically dated to the Linear Pottery culture (LBK) (ca. 5400-5000 cal. B.C.) and the Lengyel culture (ca.
4400-4000 cal. B.C.). The composition of plant remains suggests that Stipa pennata s.l. played a certain role in the economy of the Neolithic settlers. The presence of this xerothermic grass is best explained
by local gathering rather than distant transport or coming into the sediment by chance. The finding of Hierochlo? cf. australis grains represents the first identification of this plant in archaeobotanical material from Poland. This, now rare, plant
contains coumarin and for this reason could have been useful in prehistory. Other plants such as Bromus spp., Chenopodium album type, Fallopia convolvulus and Galium spp. were found in large quantities, and although common weeds now, they could also have been collected by the Neolithic
settlers. Plants such as Corylus avellana and Vaccinium vitis-idaea that are typically considered to be collected as foods are present in the studied material but in very small quantities.
Received September 17, 2001 / Accepted March 13, 2002 相似文献
9.
Despite widespread criticism, the shifting cultivation model continues to inform discussion of Neolithic farming in Europe,
beginning with early Neolithic ( Linearbandkeramik or LBK) communities concentrated in the loess belt of western-central Europe. Hundreds of LBK and later Neolithic sites have
been excavated in this region and many of them sampled for charred plant remains. Archaeobotanical data on the weed floras
harvested with crops provide the most direct archaeological evidence of crop husbandry practices, including the permanence
of crop fields, but have played a limited role in the debate over shifting cultivation. The Hambach Forest experiment, conducted
in the 1970s-80s near Cologne, Germany, provides valuable comparative data on the weed floras growing in newly cleared cultivation
plots in an area of longlived mixed oak woodland on loess-based soil. Correspondence analysis of the Hambach weed survey data
suggests that weed floras of fields managed under a shifting cultivation regime would be rich in perennial species, including
woodland perennials. Comparison of these results with Neolithic weed assemblages from the loess belt of western-central Europe
strongly suggests that Neolithic crop fields were not recently cleared of woodland vegetation but were long-established.
Received September 5, 2001 / Accepted February 26, 2002 相似文献
10.
Summary. Gliotransmission is a process in which astrocytes are dynamic elements that influence synaptic transmission and synaptogenesis.
The best-known gliotransmitters are glutamate and ATP. However, in the past decade, it has been demonstrated that D-serine,
a D-amino acid, acts as a gliotransmitter in glutamatergic synapses. The physiological relevance of D-serine is sustained
by the way in which it modulates the action of glutamatergic neurotransmission, neuronal migration and long-term potentiation
(LTP). In addition, the synthesis and degradation mechanisms of D-serine have been proposed as potential therapeutic targets
for the treatment of Alzheimer’s disease, schizophrenia and related disorders. In the present review, detailed information
is provided about the physiological and physiopathological relevance of D-serine, including metabolic and regulation aspects. 相似文献
11.
To investigate the molecular mechanisms controlling the process of cold acclimation and to identify genes involved in plant
freezing tolerance, mutations that impaired the cold acclimation capability of Arabidopsis thaliana (L.) Heynh. were screened for. A new mutation, frs1 ( freezing sensitive 1), that reduced both the constitutive freezing tolerance as well as the freezing tolerance of Arabidopsis after cold acclimation was characterized. This mutation also produced a wilty phenotype and excessive water loss. Plants
with the frs1 mutation recovered their wild-type phenotype, their capability to tolerate freezing temperatures and their capability to
retain water after an exogenous abscisic acid (ABA) treatment. Measurements of ABA revealed that frs1 mutants were ABA deficient, and complementation tests indicated that frs1 mutation was a new allele of the ABA3 locus showing that a mutation in this locus leads to an impairment of freezing tolerance. These results constitute the first
report showing that a mutation in ABA3 leads to an impairment of freezing tolerance, and not only strengthen the conclusion that ABA is required for full development
of freezing tolerance in cold-acclimated plants, but also demonstrate that ABA mediates the constitutive freezing tolerance
of Arabidopsis. Gene expression in frs1 mutants was altered in response to dehydration, suggesting that freezing tolerance in Arabidopsis depends on ABA-regulated proteins that allow plants to survive the challenges imposed by subzero temperatures, mainly freeze-induced
cellular dehydration.
Received: 16 December 1999 / Accepted: 31 March 2000 相似文献
12.
We have developed a new strategy designated SIMF (Systematic Insertional Mutagenesis of Families), to identify DNA insertions
in many members of a gene family simultaneously. This method requires only a short amino acid sequence conserved in all members
of the family to make a degenerate oligonucleotide, and a sequence from the end of the DNA insertion. The SIMF strategy was
successfully applied to the large maize R2R3 Myb family of regulatory genes, and Mutator insertions in several novel Myb genes were identified. Application of this technique to identify insertions in other large gene families could significantly
decrease the effort involved in screening at the same time for insertions in all members of groups of genes that share a limited
sequence identity.
Received: 1 June 2000 / Accepted: 26 June 2000 相似文献
13.
Summary. To date, the majority of therapeutic peptides and proteins have to be administered via parenteral routes, which are painful
and inconvenient. In order to gain sufficient high blood concentrations after oral application, various barriers in the gastrointestinal
tract have to be overcome. Apart from a poor membrane uptake and intense enzymatic degradation, this study will demonstrate
that thiol–disulphide reactions are an underestimated essential part of the presystemic metabolism. Glutathione, integrative
part of the antioxidant defence system in the gastrointestinal tract, may play an important role in the inactivation of orally
given peptides and proteins. In order to verify this hypothesis, desmopressin which bears a single disulphide bond was used
as model peptide drug. Desmopressin was incubated with GSH in various concentrations, and the extent of thiol/disulphide exchange
reactions between the peptide drug and GSH was investigated in dependence on pH and ratio of reactants determined as a function
of time via HPLC, LC-MS and Maldi-Tof-MS analyses.
Results showed that desmopressin is degraded by 1% reduced glutathione at pH 4 and pH 5.5. In presence of 0.01%, 0.1% and
1% of reduced glutathione 6.1%, 19.4% and 52.1% of desmopressin, respectively, were degraded. The masses of the conjugates
after deconvolution measured by liquid chromatography and electrospray ionisation mass spectrometric detection were m/ z 1069.67, m/ z 1376.50, m/ z 1683.40 and m/ z 2138. These molecular masses, confirmed by Maldi-Tof-MS analysis, correspond with the masses of conjugates expected in theory.
Under defined conditions, these results reveal that thiol–disulphide exchange reactions have a considerable impact on the
alteration of peptide drugs and proteins. 相似文献
14.
The French Mediterranean zone is one of the richest of the country, with 3200 species and many endemics. Because of its interest as a synthetic tool to store and manage data, an ecological Mediterranean flora database was created. Built around five tables, BASECO allows several queries about the botanical and ecological characteristics of about 1800 plants. The database was implemented in Access, which is a relational database management system. Each species is identified by a code and is characterised by several qualitative traits relating to morphology, reproduction, life forms and biogeographical distribution, including several modalities. Each trait is informed from one or two pre-defined reference botanical handbooks as much as possible. There are many different possible uses of this database, even at a huge scale, allowing to reveal patterns hard to detect with the taxonomic approach alone. 相似文献
15.
Summary. Epilepsy research relies heavily on animal models that mimic some, or all, of the clinical symptoms observed. We have previously
described a new developmental rat model of epilepsy that demonstrates both behavioural seizures and changes in hippocampal
morphology. In the current study we investigated whether these rats also show changes in cognitive performance as measured
using the Morris water maze task, and emotionality as measured using the Elevated plus maze task. In the water maze, significant
differences between male and female rats were found in several performance variables regardless of treatment. In addition,
female but not male rats, treated neonatally with domoic acid had significant impairments in learning new platform locations
in the water maze. In the elevated plus maze, a significant proportion of female rats spent more time in the open arm of the
maze following prior exposure to the maze whereas this effect was not seen in male rats. We conclude that perinatal treatment
with low doses of domoic acid results in significant gender-based changes in cognition and emotionality in adult rats. 相似文献
16.
The value of scientific studies increases and is extended when their data are stored in a manageable and accessible format. This is demonstrated through development of a raccoon ecology database (REDB) to store, manage and disseminate available peer-reviewed and unpublished data on raccoon ( Procyon lotor) biology, ecology and raccoon rabies, including citations for data sources. Over 800 documents were identified and citations for them entered into the database as literature references. Approximately 1000 trait values were entered from almost 200 of these sources. These data included estimates of population density, survival rates, rabies incubation period, litter size, body weight, dispersal distance and home-range size, often by age or sex class. Each datum is linked to a citation for its source, and to information about location and land use in the study area, time of year the study was undertaken, sample size, and variance. The relational database design enables querying and easy updating and manipulation of data. The relational data model is presented, as is its application in further developing an individual-based, spatially-explicit population model of raccoon rabies. Using information queried from the REDB benefits model development by: i) assessing the appropriateness of input parameter values, ii) providing sources for citing input values, iii) parameterising the model to different geographic regions, iv) enabling meta-analyses for evaluating model structure, as well as further contributing to parameterisation at specific locations, and v) providing biologically appropriate parameter input values for model sensitivity testing. The REDB is a useful research resource that will increase in value with ongoing inclusion of data from future raccoon and raccoon rabies studies and serves as a model for database design and research applications to other species. The database and an empty database for use with other species are available online (http://redb.nrdpfc.ca). 相似文献
17.
Summary. Imatinib, a tyrosine kinase inhibitor directed against the enzymatic domain of KIT protein, was found to produce dramatic
clinical responses in metastatic gastrointestinal stromal tumors (GISTs). However, resistance usually develops thus determining
treatment failure. The present study was performed to analyse the expression of somatostatin receptor (SSTR) subtypes, modulators
of tissue transglutaminase, in a series of GISTs and leiomyosarcomas by immunohistochemistry to identify a new potential therapeutic
target. Sixteen cases (8 males and 8 females, age range: 38–73; 11 GISTs, 4 leiomyosarcomas, 1 leiomyoma) were studied. Immunohistochemical
detection of the relevant SSTRs was performed on paraffin-embedded tissue sections, stained with polyclonal antibodies directed
against the five somatostatin receptor subtypes. We found 7 out of 16 (44%) tumors expressing all SSTRs and 14 out of 16 (87%)
tumors positive for at least 3 subtypes. SSTR2 A was the most represented subtype in the tumors studied, being expressed in approximately 70% of cases exhibiting an intense
labeling in most of these cases. The significant expression of SSTRs shown in this series of GISTs and gastrointestinal leiomyosarcomas
suggests a potential therapeutic target to be explored alone and/or in combination with other therapeutic agents in the setting
of refractory GI stromal tumors. 相似文献
18.
Proteins that are preferentially produced in developing xylem may play a substantial role in xylogenesis. To reveal the identity
of these proteins, comparative two-dimensional polyacrylamide gel electrophoresis was performed on young differentiating xylem,
mature xylem, and bark of poplar ( Populus trichocarpa Hook. cv. `Trichobel') harvested at different times of the year. The most-abundant xylem proteins were identified by microsequence
analysis. For 17 of these proteins a putative function could be assigned based on similarity with previously characterized
proteins, and for 15 out of these corresponding expressed sequence tags (ESTs) were found in the poplar EST database. The
identified xylem–preferential proteins, defined by comparing the protein patterns from xylem and bark, were all involved in
the phenylpropanoid pathway: two caffeoyl-coenzyme A O-methyltransferases (CCoAOMT), one phenylcoumaran benzylic ether reductase (PCBER), one bispecific caffeic acid/5-hydroxyferulic
acid O-methyltransferase (COMT), five S-adenosyl- L-methionine synthetases, and one homologue of glycine hydroxymethyltransferase (GHMT). Remarkably, the biological function
of the two most-abundant xylem-preferential proteins (PCBER and a GHMT homologue) remains unclear. In addition, several housekeeping
enzymes were identified: two enolases, two glutamine synthetases, one 70-kDa heat-shock cognate, one calreticulin, and one
α-tubulin. In comparison to the xylem-preferential proteins, the housekeeping proteins were expressed at significant levels
in the bark as well. Also, several additional protein spots were detected for CCoAOMT, PCBER, and COMT by immunoblot. Our
data show that for the study of xylogenesis, two-dimensional protein gel comparisons combined with systematic protein sequencing
may yield information complementary to that from EST sequencing strategies.
Received: 28 June 1999 / Accepted: 3 September 1999 相似文献
19.
In this paper a mathematical model is developed to describe the effect of nonuniform growth on the mechanical stress experienced
by cells within an avascular tumour. The constitutive law combines the stress-strain relation of linear elasticity with a
growth term that is derived by analogy with thermal expansion. To accommodate the continuous nature of the growth process,
the law relates the rate of change of the stress tensor to the rate of change of the strain (rather than relating the stress
to the strain directly). By studying three model problems which differ in detail, certain characteristic features are identified.
First, cells near the tumour boundary, where nutrient levels and cell proliferation rates are high, are under compression.
By contrast, cells towards the centre of the tumour, where nutrient levels are low and cell death dominant, are under tension.
The implications of these results and possible model developments are also discussed.
Received: 15 November 1999 / Published online: 5 May 2000 相似文献
20.
Summary. Caffeine- and taurine-containing drinks have been on the European market for about a decade, and research on the individual
constituents of these drinks indicates an improvement in cognitive performance resulting from consumption of such drinks.
In this double-blind, placebo-controlled study using 10 graduate students, we obtained the P300 components of event-related
potential (ERP) waveforms following an auditory oddball paradigm, measured motor reaction time, and applied the d2 test for
the assessment of attention. Status of mood was assessed by the “Basler-Befindlichkeitsbogen” questionnaire, a standard test
for evaluation of feelings of well-being. Measurements were made at night, prior to and starting one hour after consumption
of energy drink ingredients or placebo.
At the end of the experiment (midnight), P300 latency and motor reaction time were significantly longer compared with baseline
measurements in the placebo group, but were unchanged in the energy drink group. In the test system for evaluating feelings
of well-being, total scores, vitality scores and social extrovertedness scores were significantly decreased in the placebo
group but not in the energy drink group.
The findings clearly indicate that the mixture of three key ingredients of Red Bull R Energy Drink used in the study (caffeine, taurine, glucuronolactone) have positive effects upon human mental performance
and mood. These effects may be mediated by the action of caffeine on purinergic (adenosinergic) receptors and taurine modulation
of receptors. As half of the study cohort were non-caffeine users, the described effects cannot be explained in terms of the
restoration of plasma caffeine levels to normal following caffeine withdrawal.
Received January 5, 2000/Accepted June 5, 2000 相似文献
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