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1.
J. Robb 《Human Evolution》1994,9(3):215-229
In recent years anthropologists have made much progress in understanding ancient activities from skeletal remains. In this
paper, material from the Iron Age cemetery at Pontecagnano (VII-IV century BC) is used to illustrate activity-related traits
of eight basic categories:
These traits, and others, can be used not only singly but in conjunction to define (a) patterns of activity and occupational
specialization for individuals, and (b) distributions within society reflecting the basic division of labor by geneder and
class. 相似文献
| (1) | idiosyncratic patterns of dental wear |
| (2) | activity-related articular degeneration |
| (3) | non-pathological functional alterations (neoformations, contact facets) |
| (4) | mechanical remodelling of bone architecture |
| (5) | enthesopathies (muscular lesions) |
| (6) | traumatic lesions |
| (7) | activity-related pathologies |
| (8) | activity-related nutritional characteristics |
2.
Conclusions
This work was supported byKBN grant no. 7 A203 013 07. 相似文献
| (1) | The aminoesters inhibit glucose-stimulated proton extrusion by yeast cells. |
| (2) | The inhibitory activity depends on aliphatic carbon chain length. |
| (3) | The inhibition of proton extrusion is concentration-dependent. |
| (4) | The aminoesters stimulate quinacrine accumulation in vacuoles of yeast cells so they should possess affinities for lysosomes. |
3.
Victy Mercy Gerald 《Hydrobiologia》1976,49(2):103-109
| 1. | At 28°C conversion efficiency of total nitrogen (TN) was inversely related to size. |
| 2. | In the pre-adult stage protein nitrogen (PN) conversion efficiency was high whereas in the Post-adult stage non-protein nitrogen (NPN) conversion efficiency was high. |
| 3. | Lower temperature (20°C) was not congenial for PN conversion. |
| 4. | Higher temperature favoured PN conversion for smaller fish but NPN for larger fish. |
4.
Phytoplanktonic populations were studied in Tazenat lake by three methods:
A comparison of the results obtained gives an insight into the utilisation and transformation of energy by the biota of the lake 相似文献
| – | Primary production using 14C technic |
| – | Standing crop estimation |
| – | Amount of chlorophyll a |
5.
| 1. | The relative abundance in Lake Bonney of the trace elements studied was BM>Fe>Cu>Ni>Mo>Co, with more than 90 per cent of each element in the monimolimnion. |
| 2. | The monimolimnion contains concentrations of B which are probably toxic to phytoplankton, and Cu concentrations which are at least potetially toxic to these organisms. |
| 3. | Concentrations of B, Cu, and Mn in the mixolimnion occassionally reach potentially toxic concentrations, but there exist mitigating influences such as high calcium levels. |
| 4. | The relative amounts of trace elements contributed by the Sollas-Lacroix meltstream to the lake were Mn>Fe>Cu>NiCo>B. Except for Co and Mo, the Sollas-Lacroix meltstream did not appear to contribute trace elements in quantities which would explain the weekly changes found in the mixolimnion. |
6.
Cannibalism in teleost fish 总被引：1，自引：0，他引：1
| 1. | Cannibalistic behaviour in fish is reviewed here for the first time. |
| 2. | Cannibalism has been recorded in 36 out of 410 teleost families according to the published literature, but is considered to be more widespread than this. Finding examples of cannibalism is not difficult, and it may be more interesting to look for taxa in which the behaviour does not take place. |
| 3. | The families that have provided the most information include the Engraulididae, Esocidae, Poeciliidae, Gasterosteidae, Percidae and Cichlidae. |
| 4. | Cannibalism has been classified into seven types, depending on life-history stage, age difference between cannibal and prey, and whether or not they are related. |
| 5. | Although in captive populations, cannibalism tends to increase with increasing density and decreasing food availability, its role in population regulation has not been unequivocally demonstrated in any wild population, and obtaining the necessary data presents a formidable challenge to fish ecologists. |
| 6. | Cannibalism is of some economic importance in aquaculture, but its impact can be reduced relatively easily, by frequent grading to reduce size variability. |
| 7. | The main proximate advantage conferred by cannibalism is assumed to be nutritional. In an ultimate sense the behaviour may have evolved as a particularly effective competitive strategy. |
| 8. | Finally, it is considered that cannibalism deserves more attention from fish biologists. Investigations, however, should recognize the different types of cannibalistic interaction, and, in particular, should explore the different implications of kin and nonkin cannibalism |
7.
John C. Montgomery John A. Macdonald Gary D. Housley 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1988,163(6):827-833
| 1. | Non-visual sensory systems are likely to be important in antarctic fish since these fish inhabit an area where low light levels occur for long periods. This study was undertaken to examine the suitability of the lateral line system for prey detection. |
| 2. | Recordings were made from afferent fibres of the anterior lateral line in the antarctic fishPagothenia borchgrevinki. |
| 3. | A vibrating probe was used to stimulate the lateral line at a range of frequencies between 10 and 100 Hz. |
| 4. | Most units responded best at a stimulus frequency of 40 Hz. Below the best frequency the response typically declined steeply and at higher frequencies it was usually better sustained. |
| 5. | Crustacea identified as major components of the diet ofPagothenia borchgrevinki were individually attached to a force transducer to determine the vibrations produced by swimming movements. |
| 6. | The Fourier amplitude spectra of swimming crustaceans exhibited prominent low frequency peaks at 3–6 Hz and higher frequency peaks in the 30–40 Hz range. |
| 7. | It is concluded that the overlap in the frequency response characteristics of the anterior lateral line and the frequencies produced by crustacean prey clearly establishes the suitability of the lateral line for prey detection. |
| 8. | In several instances recordings were made from fish primary afferent neurons responding to a swimming amphipod. These recordings confirm that crustacean swimming is indeed a potent natural stimulus of the lateral line system. |
8.
Gustaaf M. Hallegraeff 《Aquatic Ecology》1976,10(2):87-95
| 1. | Spectrophotometric and paper chromatographic analyses have been made of pigments in the summer phytoplankton of eight lakes that widely differ in trophic characteristics. |
| 2. | A comparison has been made between Margalef's pigment ratio, the carotenoid/chlorophyll-a ratio, the pigment diversity expressed as the number of coloured spots on a paper chromatogram, and the pigment diversity calculated by using the Shannon formula. |
| 3. | No evidence has been found for an increase of diversity of phytoplankton pigments along a gradient from eutrophic towards oligotrophic lakes. |
| 4. | Pigment diversity cannot be simply used as a measure of lake maturity according to Margalef's ideas. |
9.
Gareth Rice Roland Clift Richard Burns 《The International Journal of Life Cycle Assessment》1997,2(1):53-59
Twelve of the main European LCA software packages currently available are examined wirh the aim of establishing which are
the most appropriate for LCAs on industrial processes. The packages performances are assessed in terms of
The review concludes with a Specification Table which summarises the facilities available on each software package.
The general conclusion from this study is that for industrially based LCAs, there are four packages which may offer advantages
over the rest. These are The Boustead Model, The Ecobilan Group’s TEAM™, PEMS 3.0 and SimaPro 3.1. 相似文献
| – | • Volume of Data |
| – | • WindowsTM environment |
| – | • Network Capabilities |
| – | • Impact Assessment |
| – | • Graphical representation of the inventory results |
| – | • Sensitivity analysis |
| – | • Units |
| – | • Cost |
| – | • User Support |
| – | • Flow Diagrams |
| – | • Burdens allocation |
| – | • Transparency of data |
| – | • Input & output parameters |
| – | • Demo version |
| – | • Quality of data |
10.
Jiří Doskočil 《Molecular and cellular biochemistry》1976,10(3):137-143
| (1) | The inactivation of various forms of nucleoside transport with reagents blocking thiol groups was studied in whole cells ofE. coli B. No positive correlation between the efficiency of active transport and the extent or rate of inactivation could be demonstrated. |
| (2) | The most efficient constitutive nucleoside-transporting system was found to comprise a specific thiol component characterized by low rate of inactivation with N-ethylmaleimide; the less efficient inducible transport and the facilitated diffusion of guanosine require the integrity of another thiol component which is rapidly inactivated with N-ethylmaleimide. |
| (3) | The constitutive nucleoside-transporting system is completely inactivated with T4 phage, while other modes of nucleoside transport are much less affected. |
| (4) | Inactivation of constitutive transporting system in cells exposed to N-ethylmaleimide for a limited period of time continues long after the inhibitor has been removed, indicating storage of the inhibitor in some cellular compartment. Addition of dithiothreitol stops the inactivation immediately. |
11.
The content of neuraminic acid (NA) of different developmental stages of trout eggs was determined.
相似文献
| 1. | The total NA increases from about 13 g NA per egg (6–8 weeks before spawning) to 50 g directly before spawning until hatching. |
| 2. | In freshly hatched fish larvae the NA-content is decreased to about 40 per cent as compared with stages before hatching. |
| 3. | The ratio of bound to free NA decreases from values of about 13.5 (6–8 weeks before spawning) to 0.85–1.2 at the hatching-stage. |
| 4. | The bound NA is almost entirely bound to sialo-glycoproteins. |
12.
In the rift valley (North-East of France/South-West of Germany), the Rhine runs freely for 300 km from South to North. The absence of natural obstacles allows the development of a very regular profile of the river. We have therefore an opportunity to study very gradual modifications of the alluvial forest communities of the fluvial corridor from upstream to downstream, according to the gradual evolution of the ecological factors, related to slope decrease and hydrological modifications.We describe, from Basel to Mainz:
相似文献
| 1) | modification of dynamic processes in the forest communities such as successional sequences or sylvigenetic mosaïcs of the terminal stages. |
| 2) | modification of species richness. |
| 3) | reduction of species diversity. |
| 4) | simplification of the forest stratification. |
| 5) | modification of efficiency of the biogeochemical cycling. |
| 6) | ecological vicariances. |
| 7) | modification in species behaviour. |
13.
Dr. Diethard Sanders 《Facies》2000,42(1):227-243
Summary On Kos island, Greece, along an investigated coastal segment 3 km in length, four adjacent sectors were distinguished, (1)
Empros beach, a rocky shore with plunging cliffs and a steeply dipping, submarine talus, (2) Thermi beach, a „coarse-clastic
beach” with a subaerial cliff fringed by a bouldery to coarse gravelly beach with poorly developed zonation, (3) Dimitra beach,
a gravelly beach with well-developed zonation, and (4) Phokas beach, a gravelly beach characterized by finer mean grain size.
The lateral variation in Holocene coastal morphology would lead to different transgressive records: „rapid” sea-level rise
that may be suggested by transgression of the rocky shore is contemporaneous with „gradual” rise recorded by transgression
of the gravelly beaches.
Dimitra beach is an about 500 m long, cuspate, microtidal, wave-dominated gravelly beach. From land offshore, in its fairweather
configuration it shows
During storm upbuilding, the foreshore sand flats disappeared, the gravel ridges were eroded and an even, more gently dipping
storm beachface developed. Beach restoration in a swell regime proceeded in feedback with the emergent fairweather beach morphology.
During ensuing fairweather, the foreshore sand flats were partly winnowed. On Dimitra beach the layer involved in beach face
to uppermost shoreface dynamics was about 1 m thick and 10–15 m wide. In fossil gravelly beach successions, features formed
during highenergy events include both berms and master bedding surfaces. Features of the waning stage are fairweather plunge
steps and relic storm/swell beachfaces (lower beachface). From cuspate gravel ridges of the upper beachface probably only
the basal part is preserved. 相似文献
| (a) | a backshore of rounded gravels to small, rounded boulders, |
| (b) | a winter storm berm paved by disc-shaped clasts, |
| (c) | a belt of beach cusps each centered by an oblique-triangular foreshore sand flat, and flanked by gravel ridges of roughly triangular shape in plan view, |
| (d) | a fairweather plunge step, |
| (e) | a. „relic storm/swell beachface” (uppermost shoreface during fairweather) of clean, rounded coarse gravels to cobbles, |
| (f) | a storm/swell plunge step, and |
| (g) | a vencer of gravels to boulders that, farther seaward, grades into submarine sand flats. |
14.
Oncostatin M, a multifunctional cytokine 总被引：6，自引：0，他引：6
15.
M. Laska R. Hudson 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1993,173(2):249-256
In a task designed to simulate olfactory-guided foraging, the ability of squirrel monkeys to discriminate an artificial 12-component odorant from 3-, 6-, 9- or 11- component submixtures was investigated. A combination of factors was found to contribute to the animals' performance:
相似文献
| 1. | Discriminability generally decreased as the number of components in the submixture increased. |
| 2 | Submixtures did not contribute equally to mixture perception, and one component in particular (cineole) disproportionately influenced stimulus discriminability. |
| 3. | Interactive effects between submixtures resulted in marked deviations from the general pattern of discriminability. |
| 4. | Changes in the relative concentration of submixtures could also influence discriminability. |
| 5. | Finally, individual differences in responsiveness to particular stimuli were apparent. |
16.
Ueda Junichi Miyamoto Kensuke Saniewski Marian Hoshino Tomoki Utsunomiya Maki Okubo Hiroshi 《Acta Physiologiae Plantarum》2002,24(2):187-194
Methyl jasmonate (JA-Me) promoted leaf abscission of succulent plant, Crassula lycopodioides, and exudation from stems and leaves after leaf abscission when it was sprayed in whole plants. Major component of the exudate
was identified as sucrose based on the results described below.
In addition, potassium and sodium were found in the exudate as major inorganic cations. These results suggest that exudate
of Crassula lycopodioides is phloem sap, and JA-Me promotes the excudation due to the inhibition of the synthesis of callose in sieve tubes of succulent
plants. 相似文献
| (1) | The reaction of the excudate was not positive in the Somogyi-Nelson method but in the phenol-sulfuric acid method. |
| (2) | The exudate was hydrolyzed with invertase of Candida utilis, after that showing a positive reaction in the Somogyi-Nelson method. |
| (3) | Only glucose and mannose were identified in the exudate after hydrolysis with trifluoroacetic acid using a gas-liquid chromatograph (GLC). |
| (4) | A single peak corresponding to the retention time of sucrose was observed using a high performance liquid chromatograph (HPLC). |
17.
To compare the efficiency of various whole cell immobilization techniques for the production of gluconic acid by Aspergillus niger were investigated using potassium ferrocyanide-treated cane molasses as the substrate. The techniques followed were:
A comparative analysis of yield has revealed that calcium alginate entrapment was the most suitable technique as it had given the maximum product yield (0.40 g gluconic acid/g total reducing sugar supplied). The properties of immobilized A.niger in sodium alginate gel have been thoroughly investigated and compared with those of free cells under most suitable conditions of fermentation. 相似文献
| (1) | Calcium alginate entrapment, |
| (2) | cross-linking with glutaraldehyde after cell permeabilization with (a) acetone, (b) toluene and (c) isopropanol and |
| (3) | development of granular catalyst. |
18.
A method for quantitative evaluation of light sources from the point of their suitability for algal cultivation is described. Two parameters are used for the evaluation:
相似文献
| (1) | amount of photons emitted in the spectral region absorbed by algae per consumed unit of electrical energy; |
| (2) | fraction of photons intercept by the algae that got effectively transformed into chemical energy. |
19.
The foraging pattern ofPolyrhachis vicina Roger, the composition of food collected, and the abundance and distribution of food sources were studied. Results showed:
相似文献
| 1. | The food collected by workers was mostly honeydew secreted by Homoptera supplemented by small insects and plant secretions. The successful foraging rate was 35% in April, 74% in June, 91 % in August, and 83 % in October. |
| 2. | The variety of food collected by workers increased from April to August and decreased from August to November, reflecting changes in the abundance of different food sources. |
| 3. | The area foraged by workers increased from 112 m2 in March to a maximum of 1196 m2 in August and decreased again to 19 m2 in November. This depended on the demand for food (number and size of colonies), the time available for foraging determined by air temperature, and the abundance and distribution of food sources. |
| 4. | Clearly, foraging for honeydew was directly related to the number of aphids at the source and inversely related to the distance from the nest to the source. |
20.
3DFS is a 3D flexible searching system for lead discovery. Version 1.0 of 3DFS was published recently (Wang, T.; Zhou, J. J. Chem. Inf. Comput. Sci., 1998, 38, 71–77). Here version 1.2 represents a substantial improvement over version 1.0. There are six major changes in version 1.2 compared to version 1.0.
Besides the above, this paper supplies:
Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1007/s0089490050231 相似文献
| 1. | A new rule of aromatic ring recognition. |
| 2. | The inclusion of multiple-type atoms and chains in queries. |
| 3. | The inclusion of more spatial constraints, especially the directions of lone pairs. |
| 4. | The improvement of the query file format. |
| 5. | The addition of genetic search for flexible search. |
| 6. | An output option for generating MOLfiles of hits. |
| 1. | More query examples. |
| 2. | A comparison between genetic search and Powell optimization. |
| 3. | More detailed comparison between 3DFS and Chem-X. |
| 4. | A preliminary application of 3DFS to K+ channel opener studies. |