Early development and pathogenesis of Lobatostoma manteri Rohde (Trematoda: Aspidogastrea)

The prosobranch Planaxis sulcatus is reported as a new natural host of Lobatostoma manteri at Heron Island, Great Barrier Reef. Planaxis sulcatus and Cerithium moniliferum were experimentally infected with large numbers of eggs. The larvae hatch in the stomach and migrate immediately along the ducts of the digestive gland into the digestive follicles. The larvae feed on the secretion and probably epithelial cells of the follicles. The acetabulum is used for adhesion to the epithelium and contributes to its erosion. In heavily infected snails, the digestive follicles disappear gradually and the larvae live in cavities lined by a flattened epithelium, parts of which show secretory activity. In snails dissected 47–49 and 65–66 days after infection, the cavities are fused, forming several large spaces which communicate with each other; only small parts of the epithelium are still secretory. Concentrations of amoebocytes occur in the walls of the digestive gland and in the wall between digestive gland and stomach of infected Planaxis. Some young worms were found in the stomach of Planaxis. No tissue reactions were seen around the stomach except in the wall between digestive gland and stomach. In Cerithium with 65–67 days old infection, the cavities contain much detritus and disintegrating cells, the epithelium is practically non-secretory and surrounded by loose connective tissue. In larvae with a body length of approximately 0·5–0·6 mm, the acetabulum begins to divide into alveoli and its anterior end grows forward; the anterior alveoli gradually increase in size and new alveoli are formed in the posterior undivided zone. In two specimens of approximately 1·3 mm body length, the whole adhesive disk was divided into half the number of alveoli usually found in adults. Allometric shifts during growth of the worms are analysed.     

The development of the rostellar hooks of Taeni pisiformis.

Beveridge I. &; Rickard M. D. 1976. The development of the rostellar hooks of Taenia pisiformis. International Journal for Parasitology6: 55–59. Growth and development of the rostellar hooks of Taenia pisiformis were examined in experimentally infected rabbits. Hook differentiation and the sizes of various parts of the hook were related to the age of cysticerci, the ability of cysticerci to resist the effects of digestive enzymes in vitro and their ability to infect dogs. Hook growth was completed 56 DAI though cysticerci were capable of evaginating in vitro 35 DAI and of infecting dogs 42 DAI. When 42-day old cysticerci were fed to dogs, no further hook growth occurred.     

INHIBITION OF CHLORELLA (CHLOROPHYCEAE) GROWTH BY FATTY ACIDS, USING THE PAPER DISC METHOD1,2

Using the paper disc-agar plate method, a number of fatty and related acids have been tested for tested activity for inhibiting the growth of Chlorella pyrenoidosa Chick. Of the saturated acids, a peak in growth inhibiting activity wax observed in the C₇–C₁₂ range, where inhibition wax observed when solutions down to 0.02 M were applied to the discs. Most of the unsaturated acids tested showed greater inhibition than did the corresponding saturated acids. Acrylic acid showed detectable inhibition at 0.001 M concentration.     

SODIUM: SOME EFFECTS ON BLUEGREEN ALGAL GROWTH1

The growth of heterocystous bluegreen algae in various concentrations of sodium, was examined in axenic culture as well as in situ studies. Anabaena cylindrica Lemm. with no Na⁺ added, suffered from decreased rates of acetylene reduction, ¹⁴C, assimilation, excretion of organic C as well as lower concentrations of chlorophyll a and particulate organic C compared to cultures supplied with 5, 10, and 50 mg Na⁺·l⁻¹ Sodium deficient algae released, extracellularly a higher percentage of previously fixed C as organic C. No differences in any parameter measured were demonstrable among cultures grown with 5, 10, and 50 mg Na⁺·l⁻¹ High nitrate concentrations (20 mg NO₃⁻·l⁻¹) resulted in decreased rates of acetylene reduction and heterocyst numbers in. Na sufficient, and Na deficient cultures: however, decreased, cellular Na content at high NO₃⁻ levels occurred only in N deficient, cultures. Higher percentages of excreted organic C occurred with increasing NO₃⁻ concentrations in Na deficient cultures. Sodium enrichment of natural bluegreen populations with the addition of 50, 100, and 200 mg Na⁺·l⁻¹ elicited neither a stimulatory nor an inhibitory response in photosynthetic C fixation. In contrast, the addition of small amounts of Na⁺ (5 mg·l⁻) resulted in increased C fixation. However, since the Na. concentration of the lake water, at ca. 5 mg Na⁺·l⁻¹, was sufficient for growth of the bluegreens present, sodium, is not assumed to be limiting under most natural conditions. No increase in in situ acetylene reduction rates occurred with additions of sodium.     

The development of the brine shrimp Artemia salina (L.): a morphometric approach

Growth allomentry in the development of the brine shrimp Artemia salina (L.) was studied. Body width and abdomen length show a negative allometric relation to body length ( k =0.35 and 0.72 respectively) over th eight instars studied. Antennule length shows a negative allometric relation in respect to body length, with a change in the value of the growth constant at Instar Five from 0.31 to 0.75. Thoracic limb length shows a high positive relation to body length ( k =3.0) until Instar Six, when a negative allometric phase ( k =0.4) follows. A change in the sign of the growth constant from positive ( k =0.45) to negative ( k =-1.4) is noted for the length of the 2nd antenna in relation to body length.     

Does directed technological change get greener: Empirical evidence from Shanghai's industrial green development transformation

The degree of technological change biased to the environmental factor is crucial to industrial sustainable development. Using the stochastic frontier analysis method based on the translog production function and the panel data of 32 industrial sub-sectors in Shanghai over 1994–2011, this paper combines the evolution dynamic of the frontier technological structure with the evolution dynamic of technological change direction to estimate the output elasticities of production factors and the growth rate of green total factor productivity. Also, we investigate and compare the degrees of technological change biased to four production factors, i.e., capital, labor, energy, and carbon emissions. The results show that the industrial green total factor productivity in Shanghai presents an overall upward trend and mainly depends on the technical efficiency change. The improvements of labor productivity, R&D intensity, and energy efficiency can effectively enhance the green technical efficiency, while capital deepening has a mitigation effect on the green technical efficiency. The technological change of Shanghai's industrial production biases to energy use and capital saving, causing a high energy demand of industrial development. Under the dual impacts of economic development and energy-saving and emission-reduction policies, the degree of technological change biased to the environmental factor (carbon emissions) displays strong and weak alternations, indicating that the green bias of industrial technological change in Shanghai is not stable and that the green transformation of industrial development model needs to be further advanced.     

A three-step method for isolating a few to several hundred milligrams of protein

An operationally simple general protein isolation method was devised from three previously available separation tools, and was tested by application to two demanding fractionation problems and for yield. One test system was the isolation by gel electrofocusing of two model proteins with pI values of 4.6 and 4.8, bovine serum albumin and ovalbumin, with a load of 220 mg each. The other test was the isolation of 10 mg of human growth hormone isohormone B from a mixture of closely migrating other isohormones. The three-step procedure comprises of: (1) separation into zones of homogeneous protein by gel electrofocusing; (2) excision of the zones of homogeneous protein from the gel followed by concentration of the protein to a small volume of solution by means of Steady-State Stacking; (3) purification from polyacrylamide-like contaminants and non-volatile buffers by gel filtration followed by lyophilization. The average overall recovery was 70--80%.     

Protein Kinase Activity of in vitro Cultured Plant Cells in Relation to Growth and Starch Metabolism

Taking tetcyclacis, a norbornenodiazentine derivative, as an example, the influence of a growth retardant on the shoot growth of sunflower, soybean, and maize seedlings grown and treated in hydroculture was investigated. In detail, the reduction in the length of various shoot sections {epicotyl, 1st internode, leaf blade) caused by the retardant was studied. At low concentrations of the retardant (\lt10^-6 M) the shortening effects are substantially attributable to an influence on cell elongation, whereas cell division is inhibited as the concentration increases (τ10^-6 M). A comparison of the effects of tetcyclacis in cell suspension cultures of appropriate plant species showed that also in this system concentrations τ 10^-6 M inhibited cell division growth, i. e. there is comparability of plant/ cell culture regarding the retardant effect on cell division. In contrast to the intact plants, however, cell elongation appears to be of only subordinate importance for the growth of cell cultures, as it has been shown using parsley cell suspension cultures.It is discussed to what extent influencing the gibberellin or sterol biosynthesis by means of tetcyclacis provides an explanation for the concentration-dependent effect on the cell division and cell elongation processes.     

Mg induced Ca deficiency under alkaline conditions

Little is known about Mg induced Ca deficiency in alkaline conditions, and the relationship between Mg induced Ca deficiency and Na induced Ca deficiency. Dilute nutrient solutions (dominated by Mg) were used to investigate the effect of Ca activity ratio (CAR) on the growth of mungbeans (Vigna radiata (L.) Wilczek cv. Emerald). At pH 9.0, root growth was reduced below a critical CAR of 0.050 (corresponding to 90% relative root length). Root growth was found to be limited more in Mg solutions than had been previously observed for Na solutions. Using a CAR equation modified with plasma membrane binding constants (to incorporate the differing antagonistic effects of Mg and Na), new critical CAR values were calculated for both Na (0.56) and Mg (0.44) dominated solutions. This modified CAR equation permits the calculation of CAR irrespective of the dominant salt present.