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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.
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   

5.
In this report we describe the most suitable protocol for callus formation and plant regeneration for cotton. We screened 15 cotton (Gossypium hirsutum L.) genotypes for metal resistance and two of them, Nazilli M-503 (M503) Nazilli 143 (N-143) selected as Cd, Cu and Ni resistant. The cotyledonary nodes from these genotypes were the best explants for regeneration of shoots (more than 90 %) and roots (50 to 70 %). Shoot apex also gave good shoot regeneration (more than 90 %) but their root regeneration efficiency was low (35 %). These results show that Murashige and Skoog (MS) media containing 0.44 μM naphthaleneacetic acid (NAA) and 0.98 μM indole-3-butyric acid (IBA) was the most suitable recipe for getting high shoot and root regeneration from cotyledonary nodes of N-143 and M503 cotton genotypes.Abbreviations
2,4 D  2,4-dichlorophenoxyacetic acid
BAP  6-benzylaminopurine
GA  gibberellic acid
IBA  indole-3-butyric acid
MS medium  Murashige and Skoog medium
NAA  naphthaleneacetic acid
This work was supported by the Textile Industry grant No. F000301 given to A.R. Memon.  相似文献   

6.
The content of neuraminic acid (NA) of different developmental stages of trout eggs was determined.
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.
  相似文献   

7.
(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.
  相似文献   

8.
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   

9.
10.
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   

11.
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   

12.
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   

13.
1.  The effect of transient forebrain ischemia on endothelin-1 (ET-1) and endothelin-3 (ET-3) production in the hippocampus of stroke-prone spontaneously hypertensive rats (SHRSPs) was investigated using immunohistochemical techniques.
2.  In SHRSPs subjected to 10-min bilateral carotid occlusion, neuronal degeneration in the CA1 pyramidal cell layer of the hippocampus was detectable at 4 days and remarkable at 7 days after reperfusion.
3.  Coinciding with neuronal degeneration, ET-1- and ET-3-like immunoreactivities were intense in the CA1 pyramidal-cell layer, the stratum lacunosum moleculare, and the CA4 subfield of the hippocampus. Almost all of the immunostained cells had morphological characteristics of astrocytes.
4.  The possibility that ET has a role in the development of neuronal cell death following transient forebrain ischemia warrants further attention.
  相似文献   

14.
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   

15.
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   

16.
1.  The excitatory and inhibitory influences on the gill ofAplysia Juliana, which are mediated by the branchial nerve, were studied by means of electrophysiological techniques. Excitatory and inhibitory pathways in the nerve were stimulated simultaneously or selectively.
2.  The branchial nerve was found to contain both excitatory and inhibitory pathways which did not contain synapses in the branchial ganglion. The excitatory pathways caused longitudinal shortening of the gill along the efferent branchial vessel and the inhibitory pathways were modulatory, depressing the longitudinal shortening.
3.  Branchial nerve stimulation elicited two types of excitatory junctional potential (EJP), which were not mediated by the branchial ganglion, in a muscle cell of the efferent branchial vessel. One type was attributed to the central motor neuron and the other type to a motor neuron which is probably situated in the neural plexus of the gill periphery.
4.  Four inhibitory pathways from the central nervous system to the gill were found.
5.  Inhibitory junctional potentials (IJPs) recorded from muscle cells of the efferent branchial vessel in response to branchial nerve stimulation did not have monosynaptic characteristics. It is thought that inhibitory motor neurons which were activated by the branchial nerve might exist at the neural plexus of the gill.
6.  A single EJP which has been induced by a stimulus pulse applied to the excitatory pathway of the branchial nerve may be depressed in an all-or-none manner by a stimulus pulse applied to the inhibitory pathway, if this is done within a distinct short period prior to or after the stimulus inducing the EJP. This indicates that the central motor neuron receives presynaptic inhibition at its periphery.
7.  The motor neurons of the neural plexus seem to receive inhibitory innervation. Suppression of endogenous EJPs in the efferent vessel persisted for a long period even after cessation of stimulation.
8.  A certain branchioganglionic neuron (BGN) was found to receive inhibitory postsynaptic potential (IPSP) inputs from the branchial nerve.
9.  The multimodality of both the excitatory and the inhibitory pathways in the branchial nerve may explain the compound neural modulations of gill movements.
  相似文献   

17.
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   

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)  The influence of sheep grazing of moderate grazing (MG), heavy grazing (HG), inordinate grazing (IG), over grazing (OG), and extinct grazing (EG) on vegetation succession was studied in the Stipa baicalensis steppe during 1984–1986.
(2)  The relationships between the relative sum of dominance ratio (RSDR) and the degree of succession (DS) at all stages of grazing succession in the Stipa baicalensis steppe were revealed in terms of the method of mathematical analysis under five grazing intensities mentioned above.
(3)  The dynamic models of grazing succession that are based on accurate grazing intensities in relation to succession courses were constructed using RSDR5, and DS. The models may explain the rules of grazing succession in the Stipa baicalensis steppe.
  相似文献   

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