BIOLOGICAL CHARACTERISTICS OF FOMES FOMENTARIUS, FOUND ON SPRUCE AND BIRCH

1967 ◽  
Vol 45 (10) ◽  
pp. 1853-1857 ◽  
Author(s):  
P. A. Suvorov

The comparative growth rates and wood destructive ability of two isolates of Tomes fomentarius (Fries) Kickx. were investigated under laboratory conditions. The pure cultures were obtained from 2-year-old fruiting bodies, growing on stumps of birch (Betula verrucosa Ehrh.) and spruce (Picea excelsa L.) trees situated in the same locality. Comparing the rates of growth of these isolates, on beer-must agar, it was found that isolates from spruce stumps grew faster and covered the entire surface of the medium in 11 days, whereas isolates from birch overgrew the same area in 16 days. The wood-destroying ability of spruce isolates was greater on pine, spruce, and oak wood blocks, whereas birch isolates were more destructive to birch, beech, aspen, alder, linden, and maple. The macro-and micro-scopic characteristics of mycelial mats of both isolates, as well as the fruiting bodies, revealed no difference between them.


1989 ◽  
Vol 54 (11) ◽  
pp. 2951-2961 ◽  
Author(s):  
Miloslav Karel ◽  
Jaroslav Nývlt

Measured growth and dissolution rates of single crystals and tablets were used to calculate the overall linear rates of growth and dissolution of CuSO4.5 H2O crystals. The growth rate for the tablet is by 20% higher than that calculated for the single crystal. It has been concluded that this difference is due to a preferred orientation of crystal faces on the tablet surface. Calculated diffusion coefficients and thicknesses of the diffusion and hydrodynamic layers in the vicinity of the growing or dissolving crystal are in good agreement with published values.



1964 ◽  
Vol 44 (3) ◽  
pp. 315-319
Author(s):  
J. M. Bell

Growth records were obtained from 12 research establishments across Canada for pigs fed according to current (1960–63) recommendations of nutrition and management. Growth curves showing age in days and weight in pounds are presented for the various breeds and crossbreds, for between-station comparisons, for comparison of upper and lower quartiles in purebred pigs, and for comparison of growth rates of purebreds with that of Yorkshires of 20 to 25 years ago.Age at 200 lb averaged from 152 to 187 days, among 10 stations for the Yorkshire breed. Pigs of each of the pure breeds reached 200 lb about 3 weeks earlier than that indicated in previous studies. Crossbred pigs of each of four different crosses grew more rapidly than average Yorkshires, some reaching 200 lb in 140 days and having gains in excess of 2.3 lb/day during the finishing period. Yorkshire, Lacombe, and Landrace pigs had similar growth curves. The upper quartile averaged 1.8 and the lower 1.4 lb/day gain between 100 and 200 lb weights. Slow-maturing pigs tended to be below average throughout life but differences in maturity between stations seemed to reflect differing rates of gain in early life, since finishing period gains were similar in 8 of 10 stations.



Author(s):  
Yajie Zou, Fang Du, Haijun Zhang, Qingxiu Hu

Nowadays the study of selenium-rich mushrooms is very popular. In the present study, selenium speciation in fruiting body of Pleurotus tuoliensis was investigated in cultivation substrates with different concentrations of sodium selenite, as well as mycelia growth and mushroom development. The results showed that the P. tuoliensis mycelia appeared good tolerance to selenium at all test concentrations. A selenium concentration of 10 mg/kg promoted fruiting of P. tuoliensis; the fruiting bodies were of good quality and had a low malformation rate. HPLC–ICP-MS determined that organic seleniums enriched in stipes and caps existed mainly in the form of selenoCystine and selenoMethionine at selenium concentrations of 10-100 mg/kg. These findings suggest that P. tuoliensis could be developed as a selenium-rich mushroom product for use as a novel dietary source of bioavailable supplemental selenium.



1930 ◽  
Vol 7 (2) ◽  
pp. 165-174
Author(s):  
M. A. TAZELAAR

Linear measurements of certain appendages and the carapace of P. carcinus were made and plotted in various ways. The following conclusions were drawn: 1. The cheliped shows heterogonic growth in both male and female, but more markedly in the male, the values of k being: male 1.8 and female 1.48 2. The pereiopods in both male and female are slightly heterogonic. The relative growth rates are graded from p3 to p5, that of p3 being slightly greater than that of p5 3. Of the ordinary pereiopods the rate of growth of p1 is the smallest in the male, but the largest in the female. 4. The difference between the rates of growth of p1 and p3 in male and female is greatest where the rate of growth in the heterogonic organ, the cheliped, is most excessive in the male. 5. The growth of the 3rd maxilliped is slightly negatively heterogonic, the value of k in the male being 0.93 and in the female 0.95. Hence there seems to be a correlation between the marked heterogony in the cheliped on the growth rate of neighbouring appendages. In those immediately posterior to the cheliped the growth rate is increased and in those anterior decreased.



2020 ◽  
Vol 367 (1) ◽  
Author(s):  
Bernhard Merget ◽  
Ulrich Dobrindt ◽  
Ken J Forbes ◽  
Norval J C Strachan ◽  
Fiona Brennan ◽  
...  

ABSTRACT Foods of plant origin are recognised as a major source of foodborne pathogens, in particular for Shigatoxigenic Escherichia coli (STEC). Most work for STEC and plant-based fresh produce has focused on the most prevalent outbreak serogroup, O157. However, non-O157 STEC is an emerging hazard, and as such it is important to characterise aspects within this group that reflect their ability to colonise alternative hosts and habitats relevant to horticultural production. Growth kinetics were quantified for a diverse set of clinical enterohaemorrhagic E. coli isolates in extracts made from different tissues of spinach, lettuce or sprouted seeds, or from soil, to represent association with ready-to-eat fresh produce production. For leafy vegetables, spinach apoplast supported the fastest rates of growth and lettuce root extracts generated the slowest growth rates. Growth rates were similar for the majority of isolates in fenugreek or alfalfa sprouted seed extracts. Monosaccharides were the major driver of bacterial growth. No correlations were found for growth rates between different serotypes or for Shigatoxin gene carriage. Thus, growth rates varied in a plant-dependent and isolate-dependent manner, for all plant or soil extracts tested, indicative of isolate-specific differences in metabolic flexibility. These findings are relevant for risk assessment of non-O157 STEC.



2001 ◽  
Vol 67 (6) ◽  
pp. 2526-2530 ◽  
Author(s):  
Bodun A. Rabiu ◽  
Andrew J. Jay ◽  
Glenn R. Gibson ◽  
Robert A. Rastall

ABSTRACT β-Galactosidase enzymes were extracted from pure cultures ofBifidobacterium angulatum, B. bifidum BB-12, B. adolescentis ANB-7, B. infantis DSM-20088, andB. pseudolongum DSM-20099 and used in glycosyl transfer reactions to synthesize oligosaccharides from lactose. At a lactose concentration of 30% (wt/wt) oligosaccharide yields of 24.7 to 47.6% occurred within 7 h. Examination of the products by thin-layer chromatography and methylation analysis revealed distinct product derived spectra from each enzyme. These were found to be different to that of Oligomate 55, a commercial prebiotic galacto-oligosaccharide. Fermentation testing of the oligosaccharides showed an increase in growth rate, compared to Oligomate 55, with products derived fromB. angulatum, B. bifidum, B. infantis, and B. pseudolongum. However B. adolescentis had a lower growth rates on its oligosaccharide compared with Oligomate 55. Mixed culture testing of the B. bifidum BS-4 oligosaccharide showed that the overall prebiotic effect was equivalent to that of Oligomate 55.



1966 ◽  
Vol 23 (6) ◽  
pp. 797-804 ◽  
Author(s):  
R. D. Humphreys

A study of herring was undertaken at the onset of a period of increased exploitation. Catches were examined for length and age composition, growth rates, length–weight relationship, sex, maturity, and fatness.Mean length (33.0 cm) and mean age (8.2 years) were smaller than recorded from earlier investigations, but growth rates have not changed appreciably. Winter-caught herring are of poor quality ranging in fat content between 2.3 and 7.7% of their wet weights.An increase in the proportion of herring with immature gonads as the season progresses and a complete gradation of otolith types from spring-spawned to fall-spawned types suggests: (1) exploitation of fish that previously did not enter the fishery until later in the season, and (2) a spawning season that extends over the spring, summer, and autumn months.



2018 ◽  
Author(s):  
Thomas P Ryan

Background. To gain a greater insight into normal and laminitic hoof growth and to be able to make comparisons between the two groups. Methods. Ten normal and three laminitic equines completed the survey, each hoof was marked with a horizontal file mark in three places, the dorsal wall and each medial and lateral quarter at about 1cm below the coronary band. Measurement of the progression of the file mark was made every 28 days, a total of 1,872 measurements were made. Results. Equine hoof growth rates showed seasonal variation with greater rates of growth during the summer months and slower rates during the winter. In normal horses growth was slower at the quarters compared to the dorsal region but the difference was not statistically significant (p>0.05). During the summer months laminitic hoof growth at the quarters was significantly faster than at the laminitic dorsal region (p< 0.05). The rate of accelerated growth at the laminitic quarters reduced during the winter months and was not statistically significant (p>0.05). Discussion. The results of this measurement survey highlighted that laminitic hoof growth is remarkably different at the quarters. This raises the question of when the transition from normal to laminitic hoof growth takes place. Traditionally changes in hoof shape during laminitis have been assumed to be a consequence of the acute phase but this has never been confirmed. The possibility exists that abnormal hoof growth could commence early in the developmental phase, the implications of abnormal hoof growth commencing at this stage are profound. A new etiology for equine laminitis then becomes possible, based on accelerated hoof growth at the quarters inducing the hoof capsule to change in shape; this process would have the capacity to subject the underlying dorsal dermal laminae to forces of extension which would be capable of destroying the laminal interface.



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