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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:
(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
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   

2.
Conclusions  
(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.
This work was supported byKBN grant no. 7 A203 013 07.  相似文献   

3.
Giles  N. 《Hydrobiologia》1994,(1):387-392
This paper reviews research results on food competition between a freshwater fish community and a breeding Tufted duck population. After the experimental removal of fish from the Main Lake, the following effects were observed:
(1)  1. Invertebrate (chironomid and gastropod) food for ducklings and adult Tufted ducks increased substantially.
(2)  2. Tufted duckling brood use of the lake increased greatly and Tufted duckling survival appears to have increased.
(3)  3. Shoveler and Pochard nested successfully for the first time.
(4)  4. Submerged aquatic macrophytes grew profusely over the lake bed for the first time leading directly to large increases in use of the Lake by wintering herbivorous waterfowl.
(5)  5. When fish were re-introduced to the Main Lake sampling bay the increases in invertebrate abundance and, to a less marked extent, macrophyte abundance were reversed.
  相似文献   

4.
5.
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
–  • 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
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   

6.
Thiolutin was found to inhibit the utilization of glucose and other growth substrates in Escherichia coli. The inhibition was detected by a sharp drop of the respiration rate after addition of the antibiotic. The actual function affected was allocated to the cytoplasmic membrane of the bacterial cells by the following evidence:
–  - spheroplasts were affected like intact cells,
–  - individual reactions of either the electron transport chain or the glycolytic pathway were not inhibited,
–  - glucose consumption in the culture stopped and the cells accumulated guanosine tetraphosphate as under starvation conditions,
–  - activation of the cell's apo-glucose dehydrogenase restored respiration via bypassing the glucose phosphotransferase system.
It was concluded that the transport of certain substrates across the membrane was inhibited.  相似文献   

7.
1.  Properties of the membrane currents ofDidinium nasutum have been investigated under voltage clamp in different solutions and after deciliation.
2.  Theearly transient Ca2+ inward current activates in a voltage-dependent manner. Inactivation is both Ca2+ -dependent and voltage-dependent.
3.  Alate Ca2+ current rises with time to peak > 50 ms and decays in the order of seconds.
4.  Activation and inactivation of the late Ca2+ current is voltage-dependent.
5.  The delayed outward current is activated by voltage. The kinetics of this K+ current, but not its amplitude, are enhanced in the presence of intracellular EGTA.
6.  The two voltage-dependent Ca2+ channels are located in the cilia, whereas all K+ channels are restricted to the somatic membrane.
  相似文献   

8.
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.
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.
Besides the above, this paper supplies:
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.
Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1007/s0089490050231  相似文献   

9.
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:
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.
  相似文献   

10.
1.  The overall rate of feeding at 28°C bears an inverse relationship to size; the time course of feeding appears to be size-independent and shows a decline with increase in time.
2.  Absorption efficiency is independent of size.
3.  The rates of absorption and conversion and conversion efficiency are inversely related to size.
4.  The rate of feeding is reflected on the rates of absorption and conversion.
  相似文献   

11.
12.
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
(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.
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   

13.
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.
(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).
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   

14.
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:
(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.
  相似文献   

15.
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:
(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.
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   

16.
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.
  相似文献   

17.
Müller  D. G.  Frenzer  K. 《Hydrobiologia》1993,(1):37-44
Culture studies with healthy and virus-infected isolates of Ectocarpus siliculosus, Feldmannia simplex and F. irregularis gave the following results:
–  Virus particles are produced in deformed reproductive organs (sporangia or gametangia) of the hosts and are released into the surrounding seawater.
–  Their infective potential is lost after several days of storage under laboratory conditions.
–  New infections occur when gametes or spores of the host get in contact with virus particles. The virus genome enters all cells of the developing new plant via mitosis.
–  Virus expression is variable, and in many cases the viability of the host is not impaired. Infected host plants may be partly fertile and pass the infection to their daughter plants.
–  Meiosis of the host can eliminate the virus genome and generate healthy progeny.
–  The genome of the Ectocarpus virus consists of dsDNA. Meiotic segregation patterns suggest an intimate association between virus genome and host chromosomes.
–  An extra-generic host range has been demonstrated for the Ectocarpus virus.
–  Field observations suggest that virus infections in ectocarpalean algae occur on all coasts of the world, and many or all Ectocarpus and Feldmannia populations are subject to contact with virus genomes.
  相似文献   

18.
19.
1.  We used laser vibrometry and free field sound stimulation to study the frequency responses of the eardrum and the lateral body wall of awake male Eleutherodactylus coqui.
2.  The eardrum snowed one of two distinct frequency responses depending on whether the glottis was open (GO response) or closed (GC response) during the measurement.
3.  The lateral body wall vibrated with a maximum amplitude close to that of the eardrum and in the same frequency range.
4.  Covering the frog's body wall with vaseline reduced the vibration amplitude of the GC response by up to 15 dB.
5.  When a closed sound delivery system was used to stimulate a local area of the body wall the eardrum also showed one of two types of responses.
6.  These results suggest that sound is transmitted via the lung cavity to the internal surface of the eardrum. This lung input has a significant influence on the vibrations of the eardrum even when the glottis is closed.
7.  The vibration amplitude of the eardrum changed with the angle of sound incidence. The directionality was most pronounced in a narrow frequency range between the two main frequencies of the conspecific advertisement call.
  相似文献   

20.
1.  Direct contact between intra-epithelial nerve endings and ciliated cells was observed in frog (Rana pipiens) palate epithelium.
2.  Electrical stimulation of the palatine nerve to the explant or the explant culture induced an increase in ciliary beat frequency in explant and outgrowth cells.
3.  Atropine inhibited electrically stimulated ciliary beat frequency increase in the explant and outgrowth cells.
4.  Gap junctional intercellular communication appears to be involved in the propagation of stimulated ciliary beat frequency increase from innervated to non-innervated ciliated cells.
  相似文献   

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