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1.
IAA and GA3 had increased the stem thickness by increasing that of cortex, phloem fibers and xylem. Each had increased straw and fiber yield/plant, but the effect was more pronounced with GA3 than IAA. The percentage of long fibers, strength and fineness increased significantly with GA3. The latter two properties decreased with IAA.  相似文献   
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Two cyanobacterial species (Nostoc entophytum and Oscillatoria angustissima) were tested as biofertilizers, substituting the normally used chemical fertilizer, for pea plant. Inoculation of soil with a suspension of each species or a combination of the two species significantly increased the germination percentage and stimulated the other measured growth parameters and photosynthetic pigment fractions of pea. However, the soil inoculation with one cyanobacterial species and the addition of the recommended dose or half the recommended dose of chemical fertilizer were usually more effective and also increased carbohydrate and protein contents of produced pea seeds. However, biofertilization combined with half the recommended dose of the chemical fertilizer was usually more effective than the addition of the full rate of the chemical fertilizer, and this may allow saving 50% of the used chemical fertilizer. The protein profile of the produced seeds showed appearance and disappearance of some protein bands in response to fertilization treatments compared to the control. Blue green algae analyses show that N. entophytum fixed more N, produced more exopolysaccharide, and contained more auxin and cytokinin than O. angustissima, the latter contained more gibberellins. These data may explain their different influences on growth and yield of pea.  相似文献   
3.
The effect of oil pollution on growth and metabolic activitiesof the fresh water algae Chlorella homosphaera and C.vulgaris was studied. The study was conducted on two locationsin the river Nile, one is oil polluted and the other is notpolluted. The assemblage of the different algal groups wasmonitored in both locations. Chlorophyta was more dominant thanCyanophyta and Bacillariophyta in both locations during allseasons except in winter when Bacillariophyta is the mostdominant group. The presence of crude oil or its refineryproducts (solar and lubricating) in the culture media of algaemarkedly influenced their growth, proteins and nucleic acidcontents. The toxicity of oil was a concentration dependent. Thelow concentrations stimulated growth, protein content andnucleic acids, whereas high concentrations had an inhibitoryeffect. Although DNA and RNA responded similarly to crude oil inthe two tested organisms, DNA showed more sensitivity than RNAto solar oil. Lubricating oil had a little phytotoxic effect onnucleic acids. Different species of algae response differentiallyto oil pollution; Chlorella vulgaris can be referred to asoil-sensitive, while Chlorella homosphaera can toleraterelatively higher concentrations of oil.  相似文献   
4.
A comparison has been made between the chaetotaxy of the gyrodactylid monogeneans Macrogyrodactylus clarii Gussev, 1961 and M. congolensis (Prudhoe, 1957) Yamaguti, 1963 from the gills and skin, respectively, of the catfish Clarias gariepinus (Burchell) from the river Nile in Egypt. Bilaterally arranged argentophilic structures on the surface of these parasites are presumed to be sensilla and are more abundant in M. clarii than in M. congolensis especially on the ventral surface (124 vs. 66). In both species these sensilla are concentrated on the head lobes and in the pharyngeal region, but there are features of the sensilla patterns that can be used to distinguish the two species. Comparison is made with sensilla patterns of other gyrodactylids. A system of cells and dendritic processes, most probably part of the nervous system, also has an affinity for silver in the two species. There are no previous records of extensive argentophilic elements in the nervous systems of monogeneans.  相似文献   
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El-Naggar  A. G.  Hedley  C. B.  Roudier  P.  Horne  D.  Clothier  B. E. 《Precision Agriculture》2021,22(4):1045-1066

Soil water content (θ) measurement is vital for accurate irrigation scheduling. Electromagnetic induction surveys can be used to map spatial variability of θ when other soil properties are uniform. However, depth-specific θ variations, essential for precision irrigation management, have been less investigated using this method. A quasi-2-dimensional inversion model, capable of inverting apparent soil electrical conductivity (ECa) data to calculate estimates of true electrical conductivity (σ) down the entire soil profile, was developed using ECa data collected by a multi-coil Dualem-421S sensor. The optimal relationships between σ and volumetric water content (θv) were established using all coil arrays of the Dualem-421S, a damping factor of 0.04, an initial model of 35 mSm?1, and with ten iterations (R2?=?0.70, bias?=?0.00 cm3cm?3, RMSE?=?0.04 cm3cm?3). These relationships were then used to derive soil profile images of these properties, and as expected, θv and σ follow similar trends down the soil profile. The derived soil profile images for θv have potential use for irrigation scheduling to two ECa-derived soil management zones under a variable rate irrigation system at this case study site. They reflect the intrinsic soil differences that occur between texture, texture transitions and drainage characteristics. The method can also be used to guide placement of soil moisture sensors for in-season monitoring of spatio-temporal variations of θv. This soil imaging method showed good potential for predicting 2D depth profiles of soil texture, moisture and drainage characteristics, and supporting soil, plant and irrigation management.

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7.
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. To explore the genetic origins of this cancer, we used whole-exome sequencing and gene copy number analyses to study 32 primary tumors. Tumors from patients with a history of tobacco use had more mutations than did tumors from patients who did not use tobacco, and tumors that were negative for human papillomavirus (HPV) had more mutations than did HPV-positive tumors. Six of the genes that were mutated in multiple tumors were assessed in up to 88 additional HNSCCs. In addition to previously described mutations in TP53, CDKN2A, PIK3CA, and HRAS, we identified mutations in FBXW7 and NOTCH1. Nearly 40% of the 28 mutations identified in NOTCH1 were predicted to truncate the gene product, suggesting that NOTCH1 may function as a tumor suppressor gene rather than an oncogene in this tumor type.  相似文献   
8.
Reactive cyclodextrin (RCD) based nanoemulsion and loaded with coconut oil in presence of Tween 80 emulsifying agent for development of antimicrobial medical cotton fabrics is the subject of current research. RCD based nanoemulsion was prepared at different stirring duration, viz, 2, 4, 6 and 24 h in presence of Tween 80. This was done in order to induce varieties in size and morphology of the nanoemulsion. The coconut oil encapsulated RCD based nanocomposite was precipitated as powder using centrifugation technique for 60 min at 4500 rpm and the resulted powder was investigated using TEM and SEM techniques. The images that provided by these techniques confirmed the nano-sized scale of the coconut oil loaded RCD nanocomposite. In addition, the entrapment efficiency of coconut oil loaded RCD based nanoemulsion after centrifugation was calculated and was found to more than 93 %; this is a proof for the successful inclusion of the coconut oil inside the cavity of RCD molecules. Moreover, the obtained RCD based nanoemulsions were applied to bleached cotton fabrics as per the pad-dry-cure method. The as treated cotton fabrics were monitored for nitrogen content, add-on, mechanical properties and morphology vis-a-vis those similarly treated fabrics but using the as prepared microemulsion of RCD loaded with coconut oil in absence of Tween 80. The morphological structure of cotton fabrics treated with the nanoemulsion in question was also examined using SEM technique. Moreover, the biological activity of the nanoemulsion finished fabrics before and after being submitted to 20 washing cycles was investigated against different types of bacteria and fungi as per the inhibition zone method. Results obtained signify: (i) deposition on the fabric of coconut oil loaded RCD nanoemulsion; (ii) the add-on of the nanoemulsion on the surface of cotton fabric is a manifestation of the stirring duration, proofing the formation of ultrafine oil nanoemulsion which penetrates the fabric surface; (iii) the finished fabrics display antimicrobial activity with clear excellent inhibition zone even after 20 washing cycles, indicating the protection of these fabrics for human beings from harmful microbes. In conclusion, the cotton fabrics treated with nanoemulsion of RCD loaded coconut oil is considered as an effective super antimicrobial medical textile against pathogenic microorganisms of both bacteria and fungus species.  相似文献   
9.
ABSTRACT

Recent research has proven that higher plants can utilize amino acids as nitrogen (N) and carbon (C) sources. Most studies have focused on single amino acids with or without inorganic N, but a range of amino acids may be expected under conditions where the main N input derives from turnover of organic N sources. This study investigated the uptake of multiple amino acids by plant roots and further the active versus passive uptake was determined. Under minimum microbial activity conditions, seedlings of wheat (Triticum aestivum L. cv. ‘Baldus’) were exposed to a series of different concentrations of seven mixed amino acids solutions. Samples of the depleted solutions were periodically collected over a period of ten hours to measure the concentration of amino acids. For all tested amino acids passive uptake was a minor contribution compared to the total uptake. The uptake rates of the amino acids were well described by single Michaelis-Menten kinetic equations with R2 ranging from 0.87 to 0.96. All of the tested amino acids showed a similar uptake pattern. Wheat plants had the highest affinity (lowest K m values) for glutamine followed by tryptophan, alanine, arginine, glycine, and serine. The V max values for amino acids uptake by wheat ranged from 2.26 for tryptophan to 16.6 μmol g?1 root FW h?1 in case of serine.  相似文献   
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