Selection of Eucalypt Plus Trees with Regard to Splitting in the Sawn Timber / SELEKSIE VAN EUCALYPTUS-PLUSBOME MET BETREKKING TOT SPLITSING IN DIE GESAAGDE HOUT     

C. H. Banks  N. J.J. van Vuuren 《Southern Forests》2013,75(1):49-52

A practical method in use in South Africa for quantifying the extent of splitting in the timber of the genus Eucalyptus in order to determine minimum standards for selection purposes, is explained. The standards are used to assist in the choice of phenotypes, the progeny of which it is hoped will produce timber which splits less.  相似文献   

Treatment of Softwoods with CCA at High Moisture Levels     

P. F. Coetzee  A. van Laar 《Southern Forests》2013,75(1):57-63

A literature study on the feasibility of treating wood with aqueous solutions at high moisture levels revealed a positive indication. The objective of the present study was to determine treatability of Pinus radiata and P. pinaster lumber at high moisture levels with commercial CCA in controlled experiments. The wood samples were treated at levels of moisture content ranging from 20 to 100%.

A statistical analysis of the data showed that specific gravity and moisture content influence solution-absorption, the effect being different for different species. Chemical analyses showed a screening out of copper- and arsenic compounds. The effect of higher moisture contents on screening out was negligible. The results indicated that certain wood species can be treated satisfactorily with CCA at moisture levels higher than 25%.  相似文献   

Calculation of E-Moduli of Beams under Third- or Centre-Point Loading: Program for HP-25 Calculator     

W. J. van Wyk  J. Myburgh 《Southern Forests》2013,75(1):79-80

A method for precision sowing Eucalyptus seeds was needed at the Florida Division of Forestry's nursery. A way to do this is to coat cleaned seeds to form uniform pellets, which are easy to handle with mechanical equipment. The small volume of the seed lots to be pelleted in Florida restricted choice of commercial companies that could do the pelleting. Small volumes (50 to 125 ml) of Eucalyptus robusta Sm. seeds were successfully pelleted in-house with a coating of fine silica sand filler and two polyvinyl alcohol (P.V.A.) binders, and by two commercial companies—Germain's, Inc. and Hilleshog Seed Co., Ltd. Nursery performance of sand-P.V.A. and Hilleshog pellets was similar to that of uncoated seeds, although germination speed was slowed. The binder Gelvatol®,¹ a coldwater soluble P.V.A., had advantages over Elvanol®, a cold-water insoluble binder. Plant yield of Germain's Filcoat® pellets was appreciably less than that of uncoated seeds, but the toughness of the Filcoat® pellets might be an advantage in some sowing situations. The Florida Division of Forestry routinely pellets seeds of several Eucalyptus species in a reciprocating-rotating pan using fine sand and Gelvatol®.  相似文献   

Cytosolic streaming in vegetative mycelium and aerial structures of Aspergillus niger     

R. Bleichrodt  A. Vinck  P. Krijgsheld  M.R. van Leeuwen  J. Dijksterhuis  H.A.B. W?sten 《Studies in Mycology》2013,74(1):31-46

Aspergillus niger forms aerial hyphae and conidiophores after a period of vegetative growth. The hyphae within the mycelium of A. niger are divided by septa. The central pore in these septa allows for cytoplasmic streaming. Here, we studied inter- and intra-compartmental streaming of the reporter protein GFP in A. niger. Expression of the gene encoding nuclear targeted GFP from the gpdA or glaA promoter resulted in strong fluorescence of nuclei within the vegetative hyphae and weak fluorescence in nuclei within the aerial structures. These data and nuclear run on experiments showed that gpdA and glaA are higher expressed in the vegetative mycelium when compared to aerial hyphae, conidiophores and conidia. Notably, gpdA or glaA driven expression of the gene encoding cytosolic GFP resulted in strongly fluorescent vegetative hyphae and aerial structures. Apparently, GFP streams from vegetative hyphae into aerial structures. This was confirmed by monitoring fluorescence of photo-activatable GFP (PA-GFP). In contrast, PA-GFP did not stream from aerial structures to vegetative hyphae. Streaming of PA-GFP within vegetative hyphae or within aerial structures of A. niger occurred at a rate of 10–15 μm s^-1. Taken together, these results not only show that GFP streams from the vegetative mycelium to aerial structures but it also indicates that its encoding RNA is not streaming. Absence of RNA streaming would explain why distinct RNA profiles were found in aerial structures and the vegetative mycelium by nuclear run on analysis and micro-array analysis.Key words: aerial hypha, Aspergillus, conidia, conidiophore, cytoplasmic streaming, development, fungus, vegetative mycelium  相似文献   

Germination of conidia of Aspergillus niger is accompanied by major changes in RNA profiles     

M.R. van Leeuwen  P. Krijgsheld  R. Bleichrodt  H. Menke  H. Stam  J. Stark  H.A.B. W?sten  J. Dijksterhuis 《Studies in Mycology》2013,74(1):59-70

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Influence of high solid concentrations on enzymatic wheat gluten hydrolysis and resulting functional properties     

N.A. Hardt  A.J. van der GootR.M. Boom 《Journal of Cereal Science》2013

Enzymatic hydrolysis at increased solid concentrations is beneficial with regard to energy and water consumption. This study examines the influence of the solid concentration on the enzymatic hydrolysis of wheat gluten and the resulting functional properties of the hydrolysate. Wheat gluten was mildly hydrolyzed at a solid concentration varying from 10% to 60% to degrees of hydrolysis (DH%) ranging from 3.2% to 10.2%. The gluten was susceptible to hydrolysis at all solid concentrations but the hydrolysis rate was influenced by increasing solid concentrations. Size-exclusion high-performance liquid chromatography revealed an increase in the ratio of peptides with a molecular mass >25 kDa for solid concentrations of 40% and 60%. The water solubility increased on hydrolysis and was independent of the solid concentration during proteolysis. The foam stability was not influenced by the solid concentration at low DH%. At DH% higher than 8%, high solid concentrations increased the foam stability, which might be related to the presence of more peptides with a molecular mass >25 kDa. In addition, we found increased reactor productivity. The results show the potential of hydrolyzing wheat gluten at high solid concentrations, which could lead to large savings for water and energy when applied industrially.  相似文献   

Fly the coop! Vertical structures influence the distribution and behaviour of laying hens in an outdoor range     

J‐L Rault  A van de Wouw  P Hemsworth 《Australian veterinary journal》2013,91(10):423-426

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Ovine lymph node survey     

J. Irwin  M. van der Wouden  M.A.F. Nelson 《New Zealand veterinary journal》2013,61(3)

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Nutritive Value of Four Soybean Products in Diets for Atlantic Salmon (Salmo salar,L.)     

Jan J. Olli  Åshild Krogdahl  Ted S. G. A. M. van den Ingh  Lars E. Brattås 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):50-60

Abstract

Four processed soybean products were evaluated as protein sources for Atlantic salmon: solvent-extracted soybean meal (SBM44), dehulled and solvent-extracted soybean meal (SBM50), dehulled full-fat soybean meal (FFSBM) and soybean concentrate (SBC). The soybean products replaced high-quality fish meal at levels corresponding to 0, 14, 28, 42 and 56% soybean protein of total protein.

Dietary inclusion of SBC, at the expense of fish meal, did not affect weight gain, carcass lipids, fecal excretion of nutrients or fecal dry matter content significantly. The nutritive value of the SBC protein appeared comparable to that of the fish meal. The three other soybean products impaired performance increasingly with increasing levels of inclusion, indicating lower nutritive value than for the fish meal. The favourable results seen with SBC indicated a great potential of soybean to become an important protein source for Atlantic salmon through improved processing.  相似文献   

Impact of two types of complete pelleted,wild ungulate feeds and two pelleted feed to hay ratios on the development of urolithogenic compounds in meat goats as a model for giraffes     

K. Sullivan  S. Freeman  E. van Heugten  K. Ange‐van Heugten  B. Wolfe  M. H. Poore 《Journal of animal physiology and animal nutrition》2013,97(3):566-576

Urolith formation has been documented in giraffes and goats. As research in giraffes poses logistical challenges, 16 buck goats were used as a model. The impact of two commercially available, pelleted feeds used for giraffes, ADF‐16 and Wild Herbivore (WH), as well as the impact of alfalfa hay and pellet proportions (20% hay:80% pellets, 80P or 80% hay:20% pellet, 20P) on the formation of urolithogenic precursors in goat urine was accomplished in a 2 × 2 factorial balance study. Complete diets contained 0.60, 0.32, 0.35 and 0.26% phosphorus (P) with calcium:P ratios of 1.60, 4.16, 3.06 and 5.23, for 80P‐ADF‐16, 20P‐ADF‐16, 80P‐WH and 20P‐WH respectively. Total faeces and urine were collected over two 5‐day periods to assess N and mineral balance. Fresh urine samples were collected and evaluated microscopically for urolithic crystal content. Urinary nitrogen (N) was lower and N retention was higher in goats fed 80P diets (p < 0.05). Intake of P was greatest for goats fed 80P‐ADF‐16; however, urinary P excretion and P retention were not affected by treatment. Crystal scores were higher in animals receiving 80P diets (p = 0.08), with crystals being composed predominantly of calcium phosphate. Urine pH was alkaline (>8) for all treatments. Urinary P concentration, a risk factor for urolithiasis, was highest (p ≤ 0.06) in the 80P‐ADF‐16 treatment (0.38 vs. 0.01, 0.02 and 0.04 mg/dl for 20P‐ADF‐16, 80P‐WH and 20P‐WH respectively), reflecting its highest dietary P level. Further investigation is recommended to determine the long‐term effects of these diets on urolithogenic compound formation.  相似文献