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261.
Biochar has been shown to be an effective organic soil amendment for the in-situ immobilization of lead (Pb).Little research has been done on the effects of biochar and zeolite interactions on Pb immobilization in contaminated calcareous soils.Therefore,the aim of this study was to investigate the effects of different levels of zeolite (2% and 4%,weight:weight) and biochars (3%,weight:weight) prepared from green compost (GB),poultry manure (PB),and municipal waste (MB) on the content of Pb in sp...  相似文献   
262.
We investigated the resistance of acetylated rattan against soft rot and other soil inhabiting micro-organisms in comparison with wood of beech and Scots pine. Calamus manan of 10 and 13 years old under rubber tree canopy was acetylated to different levels by reaction times (0.25 to 30 hours) and was tested for soft rot decay for 32 weeks. Acetylated rattan at decay protection thresholds of 15.4% and 16.2% weight gain (WG) were fully protected, as shown by both weight loss and strength loss criteria. The static bending properties of untreated rattan decayed by soft rot were significantly lower than for acetylated rattan.  相似文献   
263.
Juniperus species (juniper) are resistant to drought and have medicinal properties. In order to investigatethe condition of juniper reproduction and prevent a decline in its area, largely caused by problems in natural regeneration, the asexual reproduction of juniper has received special attention besides its sexual propagation. Among the six species of juniper in Iran, the most abundant are Juniperus polycarpos and J. excelsa. Juniperus polycarpos is ambi-sexual and J. excelsa unisexual. We show that collecting seeds in September provided for better germination than in November. In sexual propagation 82.0% and in asexual (graft) 47.6% success were achieved. Compared to a mixture of water, lime and hormones, a natural treatment of only water had better results. Diurnal change of temperature increased germination of juniper seeds over a constant temperature. Aphyllous stem cuttings from mature and old trees are less successful in rooting than leafy cuttings of juniper saplings. A treatment with Aaterra significantly reduced the percentage of rooted cuttings and total root length. Aliette, Fongarid, Octave, Benomyl, Delsene M and Maneb fungicides significantly increased the percentage of rooted cuttings but did not affect total root length. Autumn explants formed more calli than spring explants. Successful multiplication was achieved by treating buds with a mixture of 0.7% polyvinyl pyrrolidone (PVP) and 2% sucrose and cultured in a basal MS or WRC medium, with a maximum number of new buds. In consideration of extracted material of juniper species in remedy of infectious, fungus, contagious diseases as well as for drought resistance and longevity of this species in severe arid environmental conditions and various industrial applications, reproduction and seed production by micro propagation and biotechnology are necessary.  相似文献   
264.
Gesunde Pflanzen - A factorial split-plot experiment (2015–17) was carried out in a randomized complete block design with three replications at Karaj, Iran, to investigate...  相似文献   
265.
Background: Human granulocyte colony-stimulating factor (hG-CSF) can serve as valuable biopharmaceutical for research and treatment of the human blood cancer. Transplastomic plants have been emerged as a new and high potential candidate for production of recombinant biopharmaceutical proteins in comparison with transgenic plants due to extremely high level expression, biosafety and many other advantages. Methods: hG-CSF gene was cloned into pCL vector between prrn16S promoter and TpsbA terminator. The recombinant vector was coated on nanogold particles and transformed to lettuce chloroplasts through biolistic method. Callogenesis and regeneration of cotyledonary explants were obtained by Murashige and Skoog media containing 6-benzylaminopurine and 1-naphthaleneacetic acid hormones. The presence of hG-CSF gene in plastome was studied with four specific PCR primers and expression by Western immunoblotting. Results: hG-CSF gene cloning was confirmed by digestion and sequencing. Transplastomic lettuce lines were regenerated and subjected to molecular analysis. The presence of hG-CSF in plastome was confirmed by PCR using specific primers designed from the plastid genome. Western immunoblotting of extracted protein from transplastomic plants showed a 20-kDa band, which verified the expression of recombinant protein in lettuce chloroplasts. Conclusions: This study is the first report that successfully express hG-CSF gene in lettuce chloroplast. The lettuce plastome can provide a cheap and safe expression platform for producing valuable biopharmaceuticals for research and treatment.Key Words: Plastid, Human granulocyte colony-stimulating factor (hG-CSF), Biolistics, Gene targeting  相似文献   
266.
A formaldehyde-free adhesive consisting of a corn flour/NaOH adhesive mixture and a mimosa tannin/hexamine intermediate component was developed and evaluated for application to wood panels such as particleboards. The main ingredients of this adhesive include corn flour, NaOH, mimosa tannin and hexamine. This study investigated the physical properties (rheological and thermal analysis) of corn flour/NaOH and mimosa tannin/hexamine adhesives as well as mechanical properties of particleboards produced with these adhesives. Thermomechanical (TMA) experiments indicate the best performance of the adhesives to be around the relative mass proportions of 50:50 between corn flour/NaOH and mimosa tannin/hexamine. Former NMR measurements on corn starch and mimosa tannin proved that the two components behave as a polymer blend rather than co-reacting. The laboratory results show that particleboards bonded with the adhesive at this optimal ratio show good mechanical properties. Moreover, the formaldehyde emission levels obtained from boards bonded with the optimal adhesive were considerably lower to those obtained from boards made with control urea formaldehyde.  相似文献   
267.
A field experiment with maize and rice planted under four planting configurations in an intercropping system was conducted to evaluate the plant competition effects on the performance of component crops. Intercropping substantially reduced grain yields of both rice and maize. Rice yield was generally low giving monocrop yield of 1,084 kg/ha. Intercropped rice ranged between 179 kg/ha and 615 kg/ha depending on maize planting arrangement. Monocrop maize yielded highest in square planting (3,617 kg/ha) and lowest in skip-row (2,600 kg/ha) planting, but planting geometry did not influence intercropped maize yield. Monocrop maize outyielded the combined yield of component crops suggesting no yield advantage through rice-maize intercropping.  相似文献   
268.
Saffan, as a type of steroid anaesthetic, was tested to demonstrate the effect of its administration on liver function in goat. For this purpose, 40 healthy animals were divided into 4 equal groups. The 1st 2 groups were given 2 or 4 mg saffan/kg body weight (B.W.), respectively. A mixture of saffan (1 mg) and xylazine (0.1 mg)/kg B.W. was given to the 3rd group. Xylazine alone was offered to the 4th group in a concentration of 0.1 mg/kg B.W. Serum samples from all groups were analysed to measure the quantities of glucose, total protein, total and direct bilirubin as well as the activity levels of transaminases. Increased glucose levels resulted from administration of saffan which evoked more hyperglycaemia than its mixture with xylazine or xylazine alone. The hyperglycaemic effect of both doses of saffan was equivocal beyond 2 hours. The effect then differed, and glucose elevation reached the 4 fold level by 2 mg saffan and the 3 fold level by 4 mg. Total serum protein, direct and total bilirubin as well as GPT and GOT were not changed in the 4 experimental groups. This was a good indication to normal liver function in the course of administration of steroid anaesthetics to goat.  相似文献   
269.
One-hundred-and-twenty caseous lesions collected from slaughtered cattle at selected slaughterhouses in Sudan were processed for the detection of acid-fast bacteria (AFB). Sixty-four of the 120 samples showed AFB on microscopic examination after staining with the Ziehl-Neelsen method. Accordingly, it was estimated that 64 (53.3%) of the 120 caseous (purulent) lesions among the samples were due to AFB whereas 56 (46.7%) were due to other causes. Growth on Lowenstein-Jensen slants was obtained in 54 of the 120 samples. The isolated AFB were tentatively identified using microscopic and cultural characteristics. Confirmation of the phenotypic clusters was achieved by analysing the mycolic acids contents and PCR-amplification of the IS6110 insertion sequences. The above two methods have allowed the identification of Mycobacterium bovis and M. farcinogenes, the major AFB isolated from cattle in Sudan. The remaining AFB, which were negative for the above two tests, were further identified by sequencing the 16S rRNA gene. The above strategy thus allowed the identification of the isolated strains as follows: 25 (46%) M. bovis; 21 (39.9%) M. farcinogenes; 4 (7.4%) M. tuberculosis; 1 (1.9%) M. avium; 1 (1.9%) Nocardia sp., 2 (3.7%) unidentified AFB. The isolation of M. farcinogenes and M. tuberculosis, from pulmonary lymph nodes represented important findings.  相似文献   
270.
The effects of enzyme supplementation on growth, body proximate, and fatty acid composition of great sturgeon Huso huso fingerlings were investigated. Multienzyme (Kemin?) was added to diet in different concentrations (0, 250, 500, 750, and 1,000 mg/kg). Fingerlings were randomly stocked in tanks and fed with the experimental diets three times a day at 5–10% body weight for 46 days. Fingerlings fed diets containing 250 mg/kg exogenous enzyme exhibited higher weight gain and specific growth rate. This level of enzyme in the diet significantly improved feed conversion ratio. Body protein and moisture decreased slightly when fish fed with enzyme-supplemented diets while fat increased. Fingerlings fed with 500 mg/kg enzyme in diet had higher contents of n-3 essential fatty acids and lower n-6/n-3 fatty acid ratio. Optimum growth performance in great sturgeon fingerlings can be obtained by 250 mg/kg multienzyme in the diet.  相似文献   
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