A study of the relationship between mechanical characteristics and the coastal vegetation among several broad-leaf trees in Miura Peninsula in Japan

The mechanical properties of broad-leaf tree species in a maritime-wind exposed habitat in central Japan were examined. The broad-leaf trees studied were Celtis sinensis var. japonica, Ilex integra, Eurya japonica, Pittosporum tobira, Euonymus japonicus and Cinnamomum japonicum. The results obtained can be summarized briefly as follows:

1. At places with weaker wind, the number of species increased and the height of the canopy increased.
2. The fracture strength σ_m showed no dependence on tree part or branch thickness, but was constant.
3. The order of strength was Celtis sinensis var. japonica > Ilex integra > Eurya japonica > Pittosporum tobira > Euonymus japonicus > Cinnamomum japonicum, and these six species could best adapt to the wind pressure in the study area.
4. Within species, fracture strength varied directly with wind strength.
5. The strain ε_m decreased as the trunk became thicker.
6. Within species, strain energy U_m varied directly with wind strength.

     

Growth of a floating aquatic weed,Salvinia under standard conditions

1. Growth of the floating aquatic weed, Salvinia, in sterile culture was exponential for at least 2 weeks under standardized conditions.
2. Increase in light intensity or in CO₂ resulted in increases in growth rate, but did not extend the exponential period of growth.
3. This aquatic plant, like many others, discriminates against calcium relative to strontium.
4. In culture Salvinia exhibited luxury consumption of N and P.
5. Because of high C/N ratios, Salvinia may not be a favorable source of animal food, but might be useful in nutrient removal schemes.
6. In sterile culture, S. molesta produced fewer leaves than S. minima, but maintained a significant increase in leaf area and dry weight. This may be correlated with the ability of the first species to rapidly spread over tropical waterways.

     

DNA base composition and biochemical characters of Campylobacter strains

We studied the relationship between ten authentic Campylobacter fetus and two C. bubulus strains, and seventeen named vibrios of animal and human origin. All organisms fall within the genus Campylobacter, as defined. Their DNA base composition ranges from 29.8 to 35.9% (G+C). On the basis of similarity of differential biochemical tests and % (G+C), they can be divided into four closely similar groups.

1. C. fetus var. intestinalis and var. venerialis with 34.7 to 35.9% (G+C).
2. Vibrio fecalis with 32.0 to 32.8% (G+C).
3. C. bubulus with 30.1 and 30.6% (G+C).
4. The cluster V. jejuni, V. coli, Vibrio sp. from fowl, and related vibrios from man and sheep with 29.8 to 34.0% (G+C).

We propose that all the vibrios used here be included in the genus Campylobacter.     

Physiological and biochemical contributions to the taxonomy of the genus Chlorella

1. Rabbit antisera to soluble cytochrome c-553 and to ferredoxin were characterized by double immunodiffusion, the antiserum to cytochrome c-553 also by immuno-electrophoresis and by the quantitative precipitation reaction.
2. Soluble cytochromes c-553 were isolated from 11 strains of Chlorella belonging to 8 species and from one strain of Scenedesmus. Their reactivity with antiserum to soluble cytochrome c-553 from Chlorella fusca var. vacuolata 211-8b was studied.
3. With the double immunodiffusion method, the soluble cytochromes c-553 from C. fusca var. vacuolata 211-8b, C. fusca var. rubescens 232/1, C. fusca var. fusca 343, and Scenedesmus obliquus 276-3b appear immunologically identical.
4. The soluble cytochromes c-553 from C. zofingiensis 211-14a, 211-14b, and 211-14c show in the cross reaction a partial immunological relationship with that from C. fusca var. vacuolata 211-8b.
5. The soluble cytochromes c-553 from C. sorokiniana 211-8k, C. vulgaris 211-11c and 211-19, C. saccharophila 211-1 a, and C. homosphaera 211-8e (Ca.) do not show a cross reaction with that from C. fusca var. vacuolata 211-8b.
6. These results indicate that not only C. fusca var. fusca, but also C. fusca var. vacuolata, C. fusca var. rubescens, and possibly C. zofingiensis might be more closely related to the genus Scenedesmus than to the Chlorella species of the “C. vulgaris group” (i.e., C. sorokiniana, C. vulgaris, and C. saccharophila).
7. An application of the double immunodiffusion method with an antiserum to ferredoxin from C. vulgaris 211-8m revealed that the ferredoxins from 20 strains of 9 Chlorella species and from one strain of Scenedesmus do not exhibit any immunological differences as compared to the homologous antigen.

     

Studien über die Testaceenbesiedlung der Seen und Tümpel des Abisko-Gebietes (Schwedisch-Lappland)

1. From 40 waters of the Abisko-district (Sweden, Lapland) 58 samples were collected (essentially samples from sediments).
2. It is not possible to clear the origin of all discovered tests of sediments. The bottom of most waters was covered with mosses, from which vegetation, tests can come into the sediments. But also tests from other biotopes, can be found at the bottom.
3. Nevertheless we can recognize typical characters of those species living in sediments. The prevalent type is the “Difflugia-type”. Those species of Centropyxis which immigrated into sediments demonstrate a trend towards the “Difflugia-type”. The immigration is possible from Aufwuchs, mosses and soils. 62,7% of the recorded tests belong to Difflugia, 17,8% to Centropyxis.
4. The prevalent species in the sediments of the Abisko-district is Difflugia elegans var. teres, the next is D. glubolosa.
5. A great number of investigated waters contained the oligotrophic species Centropyxis aërophila. Only one lake (Ruontenjaure) shows the association of dystrophic lakes.
6. Some species are described taxonomically, for instance: Centropyxis nauwercki n.sp. C. nauwercki is very much like Difflugia, but is also connected with C. platystoma. The new species shows a trend from Centropyxis to Difflugia.
7. C. aërophila can also immigrate into the Aufwuchs. There the species has membraneous tests.
8. Geographical aspects of the sediment colonization are discussed.

     

New species and new Chinese records of Bionectriaceae (Hypocreales,Ascomycota)

Collections of bionectriaceous fungi from different areas of China were examined, in which 3 new species were encountered. Bionectria intermedia is characterized by smooth perithecia, 2-layered perithecial wall, cylindrical to clavate asci with an apical ring, ascospore striations composed of separate warts, and dimorphic conidiophores. Hydropisphaera yunnanensis has hairy ascomata which are cupulate when dry, clavate asci with a simple apex, and spinulose and very narrow ascospores fusiform and constricted at septum. Nectriopsis apiosporae possesses laterally pinched perithecia when dry, 1-layered perithecial wall, rough perithecial surface, clavate asci with a simple apex, spinulose ascospores with 3 septa, and on Apiospora sp. Four species, Bionectria epichloë, B. kowhaii, B. subquaternata and Hydropisphaera suffulta, are reported as new to China.     

Encoding of plant odours by receptor neurons in the pine weevil (Hylobius abietis) studied by linked gas chromatography-electrophysiology

Receptor neuron responses to plant volatiles, trapped by head-space procedures, were examined in the pine weevil Hylobius abietis, using gas chromatography linked with electrophysiological recordings from single neurons. Seventy-two receptor neurons were tested 173 times for various plant volatile mixtures, either via a polar or a non-polar column.

1. All responses appeared as increased firing rates which followed the concentration profiles of the GC-eluted compounds.
2. The neurons were classified separately for the two column types in 17 and 19 groups respectively, according to the compounds they responded to. It suggests that the plant odour information is encoded by a large, but limited number of receptor neuron types.
3. Most neurons responded to a limited number of compounds (1–5) and showed a marked best response to one of them, whereas additional responses to several other components which seems to be structurally similar, was recorded for some neurons. It suggests that the plant odour receptor neurons are rather narrowly than broadly tuned, and that each neuron is specialized for receiving information about one or a few related compounds.
4. Most neurons responded to monoterpenes, whereas the other neurons responded to compounds of other categories.
5. Both major and minor plant volatile components activated specifically receptor neurons.

     

Effects of the discharge of thermal effluent from a power station on Lake Wabamun,Alberta, Canada — The epipelic and epipsamic algal communities

1. The epipelic algal standing crops were increased by the discharge of thermal effluent into Lake Wabamun, particularly in the discharge canal at station (03–04) and 05.
2. The increase in the standing crop size of the epipelon was due to Oscillatoria amoena and O. borneti in the heated area, while the discharge canal provided the inoculum of the algae for the heated area of the lake.
3. At station (03–04) the increased standing crop size was also a function of increased light penetration to the sediment due to the heated effluent keeping an area of the lake free of ice during the winter.
4. The species composition of the diatoms was similar at all stations except in the discharge canal where there was a reduction in the number of diatom species.
5. Navicula cuspidate developed best in the discharge canal in the summer where water temperatures of 31°C were recorded.
6. Amphora ovalis var. pediculus was the dominant diatom species during the winter under ice-cover.
7. The heated effluent had no effect upon the standing crop or species composition of the epipsammon.
8. Results obtained from the sediment core study showed that the shallow littoral zone of the lake is very disturbed due to wind-induced wave action.

     

Die rezente Verbreitung der Flusskrebse in Hessen (Decapoda: Astacidae)

1. This investigation demonstrates the presence of three different species in Hessen (West Germany). By means of three maps the recent distribution is demonstrated.
2. Astacus astacus is still present in Hessen in small populations.
3. Austropotamobius torrentium is the rarest species and was recorded only in the Taunus-, Spessart- und Odenwald mountains.
4. Oronectes limosus, in the rivers Rhein and Main numerous before 1950, has become scarce. In the river Fulda there have been only two recordings in 1958.

     

The anaerobic metabolism of malate of Saccharomyces bailii and the partial purification and characterization of malic enzyme

1. The main pathway of the anaerobic metabolism of l-malate in Saccharomyces bailii is catalyzed by a l-malic enzyme.
2. The enzyme was purified more than 300-fold. During the purification procedure fumarase and pyruvate decarboxylase were removed completely, and malate dehydrogenase and oxalacetate decarboxylase were removed to a very large extent.
3. Manganese ions are not required for the reaction of malic enzyme of Saccharomyces bailii, but the activity of the enzyme is increased by manganese.
4. The reaction of l-malic enzyme proceeds with the coenzymes NAD and (to a lesser extent) NADP.
5. The K _m-values of the malic enzyme of Saccharomyces bailii were 10 mM for l-malate and 0.1 mM for NAD.
6. A model based on the activity and substrate affinity of malic enzyme, the intracellular concentration of malate and phosphate, and its action on fumarase, is proposed to explain the complete anaerobic degradation of malate in Saccharomyces bailii as compared with the partial decomposition of malate in Saccharomyces cerevisiae.

     

Studies on the enzymatic activities related to varied pattern of diets in the air-breathing cat fish,clarias batrachus (Linn.)

1. Specific activity of amylase, cellulase, protease and lipase in the intestines of the air-breathing catfish, Clarias batrachus (Linn.) has been studied.
2. Excepting amylase and protease, the activity of lipase and cellulase showed practically no changes with change in the nutritional status of the diets.
3. pH optima of all enzymes were between 6.9 and 7.6
4. There is reason to believe from cellulase and high amylase activity in the intestine of the species that its culture operation could be done more economically by giving them a supplementary diet from indigeneously available raw material particularly from plant origin.

     

Somatic embryogenesis and plant regeneration in garden leek

High frequency plant regeneration via somatic embryogenesis has been induced from in vitro shoot-base cultures of seedlings of garden leek (Allium porrum L.). Four main steps are involved in the procedure using BDS medium:

- shoot multiplication with 17.6 mM benzyladenine;

- induction of nodular callus from the in vitro shoot base with 9 mM 2,4-dichlorophenoxyacetic acid;

- initiation of embryogenic callus from nodular callus with 9 mM 2,4-dichlorophenoxyacetic acid +7.6 mM abscisic acid;

- plant regeneration from embryogenic callus with 9.8 mM N⁶-(2-isopentenyl)adenine.

The presence of 2,4-dichlorophenoxyacetic acid in the medium and light conditions were shown to be essential for nodular callus induction and somatic embryogenesis. Abscisic acid was not a prerequiste for somatic embryogenesis, but it significantly increased the frequency.     

An ecological study of the Ponggol Estuary in Singapore

1. An ecological study of the Ponggol Estuary was conducted from July 1965 to June 1966 and the seasonal data on physical, chemical and biological characteristics were presented.
2. The Ponggol River represents a short, narrow and shallow estuary in Singapore. The river mouth is open throughout the year and water from eastern Johore Straits drains in twice a day at high tide. The upper reach, however, is left exposed at low tide.
3. The Ponggol River was classified as a vertically and laterally homogeneous estuary and was found to exhibit a mesohaline to polyhaline environment.
4. Significant hydrological gradients from the river mouth 10 the upper reach were noted in the river system. Salinity, dissolved oxygen and pH increased towards the mouth of the river and other parameters such as nutrients, dissolved organic matter and turbidity increased towards the source.
5. Although the river received organic pollutants at the upper reach the estuary was able to discharge them fairly rapidly through regular flushing by the tides. The transient rise of organic matter did not appear to impart any serious affect on the biota in the estuary.
6. Over 98% of the phytoplankton consisted of diatoms, most of which were brought into the estuary from eastern Johore Straits. Freshwater forms were relatively few.
7. Phytoplankton biomass was considerably higher than the adjoining waters. and was reduced at the upper reach due to high turbidity of the water.
8. 80% of the zooplankton was composed of dinoflagellates,Difflugia, copepods and bivalve larvae dominating at all sections of the estuary.
9. Percentage composition of the zooplankton showed that dinoflagellates and copepod nauplii predominated at high tide whileDifflugia and bivalve larvae were abundant at low tide.
10. Zooplankton standing crop, in general, was higher towards the source at high tide but the reverse was found at low tide, i.e. standing crop increased towards the river mouth. This was attributed to the process of concentration.
11. Species composition of zooplankton was found to be more or less similar to that of the eastern Johore Straits.
12. The nekton consisted predominantly of small and juvenile fish. Close correlation of fish and copepods was found to be statistically valid and it was concluded that the fish entered the estuary to feed rather than to spawn.
13. The squids formed an important catch of the beach seine unit and were caught throughout the year.
14. The fish population could be grouped into four categories: estuarine components, euryhaline components, marine components and migratory components.
15. Benthic invertebrates were abundant. Commercially important species consisted of prawns,Metapenaeus andPenaeus, and crabs,Neptunus pelagicus andScylla serrata.
16. The river bed was inhabited predominantly by molluscs and the distribution resembled that of the sheltered shore of muddy-sand type.

     

Tres adiciones al genero Baccharis (Compositae) en Mexico

1. -Bigelowia pyramidata Rob. & Greenm. from Oaxaca proves to be a dioecious plant and is therefore transferred to the genusBaccharis.
2. -Baccharis matudae sp. nov. is described on the basis of material collected in Zacatecas and San Luis Potosí. The species is closely related toB. pyramidata (Rob. & Greenm.) Rzedowski.
3. -Baccharis zamoranensis sp. nov. is described on the basis of material collected on the border of Querétaro and Guanajuato. The taxon is related toB. multiflora H.B.K., known from central and southern Mexico.

     

The oxygen consumption of mayfly (Ephemeroptera) and stonefly (Plecoptera) larvae at different oxygen concentration

1. The aim of this investigation was to elucidate how four acquatic insect larvae, from different habitats and having different respiratory organs or types of respiratory regulation, react to a lowered oxygen concentration, and how their oxygen consumption is affected. The species investigated were the stoneflies Taeniopteryx nebulosa, Diura nanseni and Nemoura cincerea and the mayfly Cloëon dipterum.
2. The measurements were performed in a respiratory apparatus of open, flowing-water type. Its design is shown in Fig. 1. Water of known oxygen concentration was allowed to flow past the experimental larvae. The oxygen consumption of the larvae was calculated from the lowering of the oxygen concentration in which ensued.
3. The water used in the experiments was standardized, so that the electrode had the necessary stability (conductivity 470 micromhos/cm). The calcium ion was excluded in order to prevent the precipitation of CaCO₃ in the electrode capillary.
4. A large variation in the values of oxygen consumption was found as seen in Fig. 2–5. The reason for that is a corresponding variation in the motor activity of the experimental animals.
5. The physiological reasons for the general form of the curves A and C in Fig. 2–5 are discussed. The curves A and C represent oxygen consumption of the larvae at different degrees of stimulation, entailing different levels of motor activity. Curve A represents intentinally activated animals, curve C non-activated, motionless animals. The curves A and C are boundary curves corresponding to a sort of scope for activity of the animals. Over this scope area a series of curves of the same form could in principal be construed, representing different degrees of stimulation.
6. Within a certain oxygen concentration interval a motor activation was observed caused by a reduced oxygen concentration. The result of that activation can be seen in Fig. 2–5 as a zone with no or very few oxygen consumption values between curve C and D. The more easily activated the species is, the broader the zone will be. Cloën has the most narrow zone and was observed to be less activated than the other species.
7. Small larvae of Cloën (2–4 mm and 42–6 mm) and Nemoura (2–4 mm) showed clearly a greater ability to take up oxygen at low oxygen concentrations than full-grown larvae (see Fig. 8 and 9).
8. The critical point on the curve representing mean oxygen consumption as a function of oxygen concentrations was found to be at 2–5 mg O₂/1 for Taeniopteryx and Diura, at 2.2–2.5 mg O₂/1 for Cloëon, and at about 2–7 mg O₂/1 for Nemoura. The values refer to 8°. Cloëon is the species which is exposed to the greatest variations in oxygen concentration in its natural environment.
9. No influence on the oxygen consumption of starvation for 4 to 5 days was found. No difference between the oxygen consumption values obtained in the presence or in the absence of calcium ions could be observed during the experiments (Fig. 10, 11).
10. The basic picture obtained in this investigation is a set of oxygen consumption values scattered between a curve connecting highest values obtained and a curve of the standard metabolism together with a zone in which the larvae are activated by reduced oxygen concentrations. This picture is presumed to be general in aquatic animals with a well developed motor activity.

     

A study on the rate of water transport of the clam katelysia opima in relation to environmental conditions

1. The neutral red technique was employed to study the rate of filtration in Katelysia opima.
2. The weight specific water filtration was found to be greater for younger clams compared to the older ones.
3. The rate of water filtration increased with decreasing salinity.
4. Water filtration was found to increase as temperature increased, reaching a maximum at 35°C. but then sharply decreasing at 39°C.
5. Light had no significant effect on the rate of filtration.
6. Suspended matter was found to affect the rate of water filtration.
7. The rate of filtration was low at high pH and high in low pH.
8. The rate of water filtration was found to be faster during high tide than during low tide.
9. The presence of the parasitic crab, Pennotheris sp., in the mantle cavity of clams had a marked effect on the particle filtration.
10. Accidental cut of the siphon tips had no effect on the rate of filtration.

     

Charakterisierung eines phagenähnlichen Partikels aus Zellen von Nitrobacter

1. Polyhedral particles were isolated from cells of Nitrobacter winogradskyi and of Nitrobacter strains K₁, K₄ and α₁. Their physical and biological properties are characterized.
2. The investigated strains contain polyhedral particles, 1000–1200 Å in size. With increasing age of the culture more particles are found in cells of Nitrobacter. Simultaneously the number of colony producing nitritoxidants decreases.
3. In strain α₁ the loss of the capability to form colonies is connected with partial lysis of the cell and release of particles.
4. A homogeneous fraction of particles was obtained by zone density gradient centrifugation in Tris-Mg-SH-buffer.
5. The polyhedral particles have a sedimentation coefficient of s _w,20 ⁰ =825S and a CsCl-buoyant density of ?²⁵ g/cm³.
6. Based on the determined properties the particles are classified as phage-like Nitrobacter particles Nb₁.

     

Field studies on the variability of populations of Aster tripolium L. in relation to saltmarsh zonation

1. Aster tripolium is a very variable species of which a number of types have been described both on a morphological and ecological level.
2. In permanent plots along the height gradient in the salt marsh it appeared that differences in the A. tripolium subpopulations occur.
3. In the lowest zone of the marsh, dominated by Spartina anglica (Spartinion), the mean life expectancy of individual adult plants is relatively high but it is relatively low for seedlings.
4. In the higher zones of the marsh the mean life expectancy is relatively lower, but for the seedlings it is higher (Puccinellion maritimae).
5. In the Spartina-zone individual A. tripolium plants have about twice the number of shoots as the plants from the other zones.
6. The plants from the Spartina zone produce per individual more generative shoots (absolute) but these have less capitula than elsewhere in the marsh. The number of ripe seeds per head is almost constant everywhere in the marsh.

     

Growth of Nitrobacter in the presence of organic matter

1. Culture filtrates of heterotrophic bacteria were tested for their stimulatory effect on nitrification of three strains of Nitrobacter.
2. Yeast extract-peptone solution, in which Pseudomonas fluorescens had grown, after removal of the cells was added to autotrophically growing cultures of Nitrobacter agilis; it caused a stimulated nitrite oxidation and growth of Nitrobacter agilis.
3. The degree of stimulation depended on: a) the proportion of the culture filtrate to the autotrophic medium; b) the composition of the complex medium in which Pseudomonas fluorescens had been grown; c) the time the heterotrophic bacterium had been grown in the complex medium.
4. The stimulatory effect was highest with Nitrobacter agilis, less with Nitrobacter winogradskyi and negligible with Nitrobacter K ₄.
5. It was possible to adapt nitrifying cells of Nitrobacter agilis to higher concentrations of yeast extract and peptone. After the nitrite had been completely oxidized the cell-N still increased up to 30% before growth stopped.