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A pot experiment was consummated on Rhaphiolepis umbellata seedlings grown under seran greenhouse at Al-Zohriya Garden, Hort. Res. Inst., ARC, Giza, Egypt during the two consecutive seasons 2017 and 2018, to study effects of five foliar spray treatments of a mixture containing three growth regulators (PGR), at the same concentration for each, on plant growth and chemical composition. The three-tested PGR were NAA, GA3 and BA, while the five concentrations for each were 0 (control treatment), 100, 200, 300 and 400 ppm. Obtained results indicated that, generally, all recorded vegetative and root growth traits; i.e., plant height, stem diameter, numbers of branches and number of leaves/plant, leaf area, root length and number of roots/plant increased significantly under the effect of all tested PGR treatments, compared to the control plants. The highest increases in this regard were recorded in plants sprayed with PGR at 200 ppm, while the least values were found in the untreated control plants, followed by plants sprayed with the highest PGR concentration of 400 ppm for the two seasons. The same trend was noticed in respect of leaf chemical constituents, as plants that recorded the highest vegetative and root growth (treated 200 ppm PGR) also contained the highest values of total chlorophyll and carotenoids (mg/g f.w.) as well as percentages oftotal carbohydrate, N, P and K in leaf tissues. Accordingly, it could be recommended to apply the mixture of these three growth regulators 200 ppm on seedlings of Rhaphiolepis umbellata, two times monthly during the growing season to get the best plant growth and quality.

The biodiversity of aquatic and terrestrial ecosystems in Egypt including seas, lakes, and soils with high salinity levels provides rich habitats for flourishing halophilic microorganisms. The present study aims to isolate halophilic bacteria from sixteen samples representing ecosystems with various geographic locations and surveying the mechanisms by which they can tolerate the osmotic stress. Results revealed the highest salinity levels; sodium, chloride, sulfate, magnesium, calcium, and potassium concentrations in water sample of Wadi El-Natroun Lake since the total number of halophilic bacteria was4.68/g and the largest number of halophilic genera was observed in the northern coast of Matrouh governorate. A total of 60 bacterial isolates selected during (June-October 2015) were screened using thin layer chromatography for osmolyte; ectoine. It has the ability to decrease the harmful effects of high salinity, heating, freezing, drying as well as oxygen radicals and other denaturing agents in halophiles. Quantitative estimation of ectoine by high-performance liquid chromatography showed its yield was ranged between 185 and 700 mg/l. Using biochemical tests and 16s rRNA technology, the most active ectoine-producers were identified as Vibrio sp. CS1 and Salinivibrio costicola SH3. The yielded ectoine was purified using cation exchange chromatography (Dowex 50 WX8 resin) and its physicochemical properties were investigated using standard methodology. Characterization of purified ectoine via nuclear magnetic resonance and fourier transform infrared spectroscopy showed the similarity between bacterial ectoine and the authentic was nearly 99%.

The study investigated the effect of in-feed administration of dried thyme leaf and celery seed mixture (at 1 : 1 DM basis) compared with salinomycin ionophore on milk production and milk nutritive value of Barki ewes. Thirty ewes (37.5 ± 1.8 kg), divided into 3 treatment groups, were fed: (1) a complete control diet comprising concentrates and fodder maize (Zea mays L.) at 60 : 40 dry matter basis, (2) the control diet plus 20 g of thyme and celery mixture supplementation and (3) the control diet supplemented with 1 g of salinomycin per ewe daily for 90 days. Inclusion of thyme–celery treatment increased (P < 0.05) weight gain, average daily gain, milk yield, milk component yields, and feed efficiency, without affecting milk composition. In addition, the thyme–celery treatment enhanced (P < 0.05) nutrient intake and digestibility, total ruminal volatile fatty acids, branched chain fatty acids, and acetate proportions and decreased ammonia-N concentration. Thyme–celery treatment increased (P < 0.05) serum glucose, thyroxine, and glutamate-pyruvate transaminase concentrations. It is concluded that the thyme and celery mixture (1 : 1 DM basis) at 20 g per lactating ewe daily can replace the salinomycin ionophore. Enhanced feed utilization and lactational performance as well as milk nutritive value for human consumption were observed with the natural additive mixture supplementation.

This study was aimed to compare between the effects of different chemical forms of Zn and cupper[ionic forms (CuSO4), (Zn SO4) and chelated forms of [Cu Zn (II) HEDTA and Cu (II) HEDTA], whereas, HEDTA is N-(hydroxyethyl) ethylenediamine triacetic acid, applied at micromolar concentrations in the nutrient solution] of Phaseolus Vulgaris plants grown hydroponically under conditions of iron deficiency (- Fe) were investigated. Plant variants (– Fe + 2 µM Cu2+) and (– Fe+ 20 µM Zn2+) with extremely strong chlorosis were examined for investigations to take after the recuperation of leaf greening after treatment with Cu(II)HEDTA created leaf greening in the two variations, particularly strong for the recently which created leaf, as it appeared with chlorophyll estimations. Changes of plasma membrane reductase movement (PMRA) in roots after treatment with ionic or chelated copper were followed in (+Fe) and (– Fe) plants. The results show the increment of ferric-chelate reductase action (with substrate of Fe (III) HEDTA). Then, the cupric-chelate Cu (II) HEDTA, connected at similar level in arrangements with (– Fe) plants, kept up the high encouragement of plasma membrane ferric-chelate reductase activity. It can be concluded that the treatment with Cu (II) HEDTA enhanced the development and root plasma membrane reductase activity (PMRA) and additionally iron deficiency reactions of phaseolus plants. Regard to cell compounds increase, measurements of 20 μM of Zn altogether developed the action of the protein superoxide dismutase and peroxidase.

Numerous applications of compatible salts (osmolytes) as ectoine in food and pharmaceutical industries have been intensively increased nowadays. Decreasing the cost of industrial production of ectoine using low-cost cultivation media and improving the yield through modeling procedures are the main scopes of the present study. Three statistical design experiments have been successfully applied for screening the parameters affecting the production process, studying the relations among parameters and optimizing the production using response surface methodology. A novel semi-synthetic medium based on hydrolyzed corn gluten meal has been developed to cultivate moderate halophilic bacterial strains; Vibrio sp. CS1 and Salinivibrio costicola SH3, and support ectoine synthesis under salinity stress. Two regression equations describe the production process in the new medium have been formulated for each bacterial strain. Response surface optimizer of the central composite model predicts the maximum ectoine production is achieved at incubation time; 63.7 h, pH; 7.47 and salinity; 7.27% for Vibrio sp. CS1 whereas these variables should be adjusted at 56.95 h, 7.089 and 10.34%; on the same order regarding Salinivibrio costicola SH3. In application studies, 50 µg ectoine decreases RBCs hemolysis due to streptolysin O toxin by 21.7% within ten minutes. In addition, 2% ectoine succeeds to increase the viability of lactic acid bacteria in Yogurt as a classic example of functional food during the storage period (7 days). The present study emphasizes on modeling the process of ectoine production by halophilic bacteria as well as its activity as a cryoprotectant agent.

Four different solvents were used to study their efficiency on pigments extraction from three different algal species of Chlorella vulgaris, Spirulina platensis and Nannochloropsis oculata. Dimethylsulfoxide, acetone, ethanol and methanol were used in the extraction process. The experiment was performed in both of fresh and oven dried algal samples. Chlorophylls a, b, total chlorophyll and total carotene concentrations were determined spectrophotometrically and by HPLC technique. The spectrophotometric method revealed that, dimethylsulfoxide surpasses all other used solvents in all species and all pigments in fresh samples except for chlorophyll a of N. oculata, whereas acetone was more effective than the others in fresh and dry sample. For the dried sample of C. vulgaris, methanol gave the maximum extractability with chlorophyll a while chlorophyll b and total chlorophyll were found be maximum in dimethylsulfoxide solvent. In Spirulina, methanol represented the maximum chlorophyll a and total chlorophyll for the dried samples. Total carotene was found to be higher in ethanol solvent with both C. vulgaris and N. oculata but dimethylsulfoxide surpasses the other solvents with S. platensis. HPLC results emphasized that, acetone surpasses all other used solvent in fresh samples and methanol was ideal solvent in dry samples of C. vulgaris. Dimethylsulfoxide represented the maximum chlorophyll a and total carotene with Spirulina in both samples. Methanol was the best solvent for extraction of all pigments with N. oculata except with â-carotene of dry sample, ethanol was the best solvent.

Sixty-three isolates belonging to the genus Pseudomonas were isolated from different environmental sources including; soil, water and clinical specimens. Twenty out of them were identified as Pseudomonas aeruginosa and individually screened for pyocyanin production. P. aeruginosa R 1; isolated from rice-cultivated soil and P. aeruginosa U 3 selected from clinical specimen (Urinary tract infection) were the highest pyocyanin producers; pyocyanin production reached 9.3 and 5.9 μg/ml, respectively on synthetic glucose supplemented nutrient medium (GSNB). The identification of both selected strains ( P. aeruginosa R 1 and P. aeruginosa U 3 ) was confirmed by 16S rRNA, the similarity with other strains available in database was 97% (with P. aeruginosa FPVC 14) and 94% (with P. aeruginosa 13.A), respectively. P. aeruginosa R 1 and P. aeruginosa U 3 are accessed at gene bank with accession numbers KM924432 and KM603511, in the same order. Pyocyanin was extracted by standard methods, purified by column chromatography and characterized by UV-Vis absorption, mass spectrometry and nuclear magnetic resonance. The antimicrobial activity of purified pyocyanin against multi-drug resistant microbes was investigated; the efficiency of pyocyanin was more obvious in Gram +ve bacteria than Gram−ve bacteria and yeast. To reduce the cost of pyocyanin production, a new conventional medium based on cotton seed meal supplemented with peptone was designed. The pyocyanin production of both selected strains P. aeruginosa R 1 and P. aeruginosa U 3 using the new medium is increased by 30.1% and 17.2%, respectively in comparison with synthetic GSNB medium, while the cost of production process is reduced by 56.7%.

A water culture experiment was carried out in the Department of Fertilization Technology at National Research Centre, Cairo, Egypt, to investigate the effect of Ascorbic Acid (AsA) foliar application and salinity stress (100 ppm and 100 mmoL NaCl) on growth, nutrients concentration and some biochemical parameters of two kidney bean (Phaseulus Vulgaris L.) cultivars. Salinity caused significant reduction in growth parameters (leaves and root dry weights) and some of biochemical parameters (nutrients concentration, photosynthesis pigment, Carbonic Anhydrase Activity (CAA), antioxidant enzyme activity Peroxidase (POD) and lipid peroxidation). The reduction effect on Paulista cultivar was higher than Nebraska cultivar at 100 mM NaCl salinity stress. Meanwhile, POD activity was increased under salt stress conditions. Lipid Peroxidation (LP) under 100 mmoL NaCl salinity was significantly increased. The two cultivars showed an increase in MDA content with NaCl salinity stress, but the increase in sensitive cultivars Paulista was higher than that in salt-tolerant Nebraska cultivar. Application of (AsA) not only mitigated the inhibitory effect of salt stress in both kidney bean cultivars, but also in some cases induced a stimulatory effect greater than that estimated in the control plants on growth parameters which were accompanied by marked increases in nutrients concentration and photosynthetic system (pigments and carbonic anhydrase activity). Ascorbic Acid (AsA) has been shown to be an essential antioxidant; agent may act as a scavenger of ROS for mitigating the injury on bio-membranes under salt stress. Therefore, this study suggested that (AsA) application may induce an adaptive response in kidney bean through stimulation of the antioxidant enzymes activities, photosynthesis processes and lower lipid peroxidation, in Nebraska relative to Paulista may contribute to salt tolerance mechanism in Nebraska.

Using microorganisms or their secondary products, especially volatile organic compounds (VOCs), to control wood infection by fungi has been exploited in recent years. A total of 17 local microbial isolates were screened for growth inhibition of wood-pathogenic fungi on solid artificial medium. Lactobacillus plantarum was selected as the most active VOC producer since it reduced the growth of sapstain fungi by 60–90% and that of wood-degrading fungi by 20–60%. During the interaction between the majority of the tested wood-pathogenic fungi and VOCs emitted by L. plantarum on wood blocks, both hyphal growth and conidial formation were inhibited. It was also observed that loss of wood dry weight and wood strength due to the action of pathogenic fungi was decreased to negligible values by exposing wood blocks to VOCs emitted by L. plantarum. The VOCs produced were trapped using a simple method and quantified by GC/MS. The main constituents of the VOC profile were 1,2-benzenedicarboxylic acid, dibutyl ester, isopropyl myristate, n-nonadecane, octadecane and n-eicosane. This study also evaluated using gamma radiation to enhance microbial production of VOCs.

Maize and chickpea plants were grown in a controlled environment with 0.5 M Zn or without Zn and various photosynthetic reactions were studied. The chlorophyll level, the rate of photosynthesis and photosystem II activity, the activity of carboxylating enzymes and that of carbonic anhydrase were suppressed by Zn deficiency in both plant species. Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) was quantified using polyacrylamide gel electrophoresis. Growing plants in a medium without Zn caused a decrease in the total protein level and in the levels of large and small subunits of Rubisco.

Three algae species belonging to Chlorophyta; i.e Chlorella sp ., Scenedesmus sp . and Haematococcus pluvialis, were incubated under different concentrations of the photosynthetic inhibitor dichlorophynyldimethylurea (DCMU). Algae were treated with 0, 1, 2, 4 and 8x10-5M DCMU added to N8 macronutrient solution containing ammonium acetate instead of potassium nitrate. The measured parameters were optical density, cell count, medium reaction (pH), total chlorophyll, total carotenoids, crude protein and lipids as ether extract. Results showed that DCMU inhibited growth as optical density for both Scenedesmus sp. and Chlorella sp. H. pluvialis exhibited more resistance against all given concentrations. Chlorophyll reached the maximum with lower and moderate levels of DCMU with Scenedesmus sp. and Chlorella sp. As for H. pluvialis, all used concentrations inhibited chlorophyll accumulation. A different manner was observed on carotenoids accumulation, where the decline of chlorophyll was associated with the decomposition of crude protein and rise in carotenoids and lipids content especially with H. pluvialis.

This work was conducted using two different open plate systems, mainly used as inoculum unit, to study the effect of culture volume, growth surface and flow rate on growth of the alga Scenedesmus sp. For inoculum preparation, laboratory growth was performed using N8 macronutrients solution with PAZ trace elements mixture. Out door production was heterotrophically achieved using a mixture of 0.3 g.l-1 urea (46.5%), 0.05 g.l-1 SoulPotas (mini.50.0% K2O & 46.0% SO3), 0.1ml.l-1 phosphoric acid (85%) and 6mM acetic acid (5%) under continuous illumination. The first unit, of 1000 L capacity, exposed area of 8.78m2, pumping power of 2.0 hp through out 45 mm polyethylene pipe system, 54-60 m3.h-1 of follow rate and fueling valve of 63 mm was compared with the modified unit. The modification was operated based on increasing volume capacity to 2000 L, 19.0-36 m3.h-1 of flow rate with large exposed area of 13.73 m2 and higher pumping power (2.5 hp) through 63 mm polyethylene pipe system. The out let was also modified using total width outlet instead of whole outlet of 63 mm diameter. The modifications done increased growth of alga in terms of dry weight or total chlorophyll. The increment of growth, about 33.0% of dry weight and about 25.0% of total chlorophyll, recorded the variation of growth among two units. Growth characteristics represented variable results.

Leaf protein concentrates were prepared from 25 different plant species. The concentrates contained acceptable levels of all essential amino acids; except methionine which was limiting with chemical scores ranging between 13.5-96%. LPCs from sesbania, nebergrass, lufa and sweet pepper were lethal to the rats. PER ranged between 0.28 for safflower LPC up to 1.95 for rape. Positive nitrogen balance was obtained with diets based on LPCs with mean values ranging between 6.4 and 22.42 mg N per day. True nitrogen digestibility fluctuated between 72.4% for sweet potato LPC up to 97.9% for LPC prepared from safflower. BV ranged between 60.5 for sunflower LPC to 97.26 for carrot LPC. NPU values of LPCs were 49.4 for sunflower LPC up to 86.5% for rape LPC. There was a positive correlation coefficient between BV and the respective NPU. Highest utilizable protein was obtained with turnip LPC. Tested LPC's contain 0.6-6.8% tannin. Saponin was absent in 11 LPCs. Lufa LPC showed the highest saponin content followed by nebergrass and sesbania LPCs. Trypsin inhibitory activity was quite low. Prelimenary results show that rats consumed diet based on lufa, nebergrass and sesbania LPCs died within the first few days of the experiment. Low growth rates were obtained for drum-dried samples prepared from carrot, but this was not the case for drum-dried samples prepared from chard. The activity of liver alanine amino transferase was also determined and indicated toxicity of some LPCs to liver.

This work investigate the effect of gamma irradiation on a heavy type of concrete, constructed for nuclear reactor shield. The effect of gamma irradiation was studied after annealing the concrete samples at 300°C for 24 hours in air.

The substitution effect of Te, with different concentrations, on the electrical and thermal properties of the quaternary chalcogenide semiconducting films Ge 20 As 30 Se 50− x Te x , x =0, 20, 30 and 40, have been studied. Dependence of d.c. conductivity on composition has been reported. It was found that the activation energy decreases with increasing Te content. The obtained results have been interpreted in the frame of the model proposed by Mott and Davis (1979). It has also been observed that the increase of Te was followed by a decrease in the glass transition temperature. In other words, the addition of Te decreases the stability of the formed glass.

In comparison with other chalcogenide glassy systems, less attention has been paid to the quasi-ternary (quaternary) system As2(S, Se, Te)3. In this paper, thermal methods were used to characterize ten different quaternary homogenous semiconductor glasses that were prepared by mixing the stoichiometric binary systems As2S3, As2Se3 and As2Te3.

X-ray diffraction studies for sixteen compositions of recrystallized samples for TlxSe1−x system, withx=0.0 up tox=0.9, shows the existence of four crystalline phases. Crystalline hexagonal selenium exists in the range ofx=0.0 tox=0.4, which is a glass region boundary, indicating the responsibility of selenium for forming Se−Tl glasses. Tetragonal SeTl crystalline phase exists in the wide range ofx=0.005 tox=0.9, and tetragonal SeTl2 crystalline phase was observed in the range ofx=0.58 tox=0.9. The α-thallium hexagonal phase was observed in the range ofx=0.7 tox=0.9. The effect of thallium content on the interplanar spacing (dhkl) and relative intensities (I/I0) of the diffraction lines of elemental selenium is reported.

The effect of thallium on the phenomena accompanying the thermally induced structural changes in various glasses of the chalcogenide system (As2Se3)1-xTlx, withx = 0.0 to 0.7, has been investigated using DTA measurements. The crystallization kinetic parameters of the glasses (e.g. crystallization mode,n, rate of reaction,K, and activation energy,E) have been evaluated applying a single-scan technique, and compared with those obtained from the shift in the exothermic peaks (Kissinger model). The kinetic parameter results indicate a discontinuity near thallium concentration of 2.25×1021 atoms cm−3 (x = 0.25) where there is a peak in bothE(3 eV) andn (2.7) and a corresponding dip inK(6.7×10−3).

Pot experiments were conducted over 3 successive seasons using wheat Giza 155 grown in normal or low (50 % of normal) light intensity. Concentrations of 50, 100, 500, 1000 or 2500 ppm CMH were sprayed at tillering, early stem extension, late stem extension or heading. Grain weight/plant, specific grain weight, grain number/ear and ear number/plant were increased with lower concentrations of CMH treatments only at the first 2 stages under varied light intensity. During both tillering and early stem extension, CMH spraying increased activities of α-amylase and β-fructofuranosidase in leaves leading to more accumulation of total carbohydrates in grains and consequently more grain production/plant. Such effect occurred with 50–500 ppm CMH under normal light intensity as well as with all concentrations of this compound under low intensity. Meanwhile, 1000 and 2500 ppm CMH resulted in growth inhibition.

Radiophotosynthesis has been carried out using the unicellular green algea Scenedesmus acutus grown, as a substrate for preparing some carbon-14 labelled amino acids. Gaseous 14CO2, in an air tight photosynthesis chamber or NaH14CO3 solution, in an ordinary photosynthesis chamber, were used as radioactive carbon sources. The yields, radiochemical yields and specific activities of the formed radioactive products are reported in both cases. The results obtained clearly showed the advantages of using the NaH14CO3 method. In that case the process was by far less tedious. Moreover, the chemical and radiochemical yields of the formed amino acids were relatively much more higher than the values obtained on using 14CO2 in the tight photosynthesis chamber.

Nitrogen use per unit area in Egyptian agriculture is over 300 kg ha-1. An annual average increase of about 2% till year 2000 was estimated. Fertilizers use is characterised by excessive N application, moderate P use and neglection of K and micronutrients. Consequently, nutrient imbalance occurs in crop plants. Subsidising N fertilizers resulted in their misuse and increasing losses. Efficiency of N use in different areas and crops is low. High nitrate concentrations were detected in drainage as well as ground water. Subsidy was removed and fertilizers handling was left to the free market in 1992/93, which resulted in drastic price increases. It could be demonstrated for many years and in farmers fields that yields can be considerably increased (20%) through balanced fertilizers use based on soil testing and plant analysis and adjusted according to the prevailing farming system, leading to more return and less N-use. Use of micronutrients foliar fertilizers leads to increase in root growth and higher uptake of macronutrients. Use of relatively high rates of fertilizers is still a must, however it should be optimised to obtain the highest possible efficiency. Making crop and location specific fertilizer recommendations available to farmers helps in increasing high quality yields, which results in high economic benefits, keeping agricultural production sustainable and decreasing pollution.

EDTA-chelated or sulphate salts of Mn-Zn-Fe combination were sprayed at different concentrations with or without urea on plants 30 days after sowing in pot experiments. Results showed that mixing urea with chelated and non-chelated micronutrient compounds increased intake of micronutrients in comparison with either micronutrients without urea or control treatment.

CCC was sprayed 3 times on carnation cultivar ‘Hanacy’ grown in pots, in concentrations ranging from 10 to 100 p.p.m. CCC treatments generally enhanced floral initiation. This effect was reflected by earlier flower production and considerable increase in flower yield. Enhancement of floral initiation by CCC was coincident with increased amylase and invertase activities as well as with higher content of reducing sugars.

The homogeneous glass-forming region for air-quenched melts in the binary chalcogenide system SSe is reported together with metastable melt crystallization temperatures and differential thermal analysis data for glass powder heated at different rates in a nitrogen atmosphere under standardized conditions. The compositional dependence of the electrical activation energy, the density and the glass transition temperature were measured in an effort to correlate the chemical binding with the physical properties. Myuller's valence theory of the electrical conductivity of glasses was applied to calculate the “steric factor” β defining the degree of departure of σ 0 (exp) from σ 0 (theor). A thermodynamic technique was used to study the devitrification process for different amorphous compositions of the system SSe. New data concerning the compositional dependence of the non-isothermal crystallization kinetics parameters are presented and discussed.

Protein concentrates, were isolated from three by-products, defatted soya-bean, rice-bran and protelan. The conditions of maximum protein isolation differed according to the material used. Concentrates of 55.70%, 22.41% and 57.45% protein could be obtained from soya-bean, rice-bran and protelan; respectively. Hydrogen peroxide was found to increase the isolated nitrogen from protelan and rice-bran, however, in soya-bean it was without any positive effect. Essential amino acid contents were found corresponding to the amino acid of the FAO recommended amino acid composition except for methionine in all cases and lysine in protelan.

Summary The effect of urea application at various levels to different Egyptian soils on the microbial densities, urease activity, and mineralization of urea was studied in laboratory experiments. The investigated soils were representing loamy, saline, alkali, sandy, and calcareous regions. The levels of urea chosen, being within the farmer application rate, were 50, 100, 150, 200, and 250 kg/ fed. The results revealed the following conclusions: Application of urea at different rates generally increased the total microbial flora in different soils, especially in the early experimental period. The activity of urease enzyme, expressed as mg NH4-N/100g soil/hr, showed highest values in loamy soil at zero time, followed by saline and alkali soils, while calcareous and sandy soils showed the lowest values. After application of urea the enzyme activity increased, especially during the first stage of the experiment, then gradually decreased. The differences between treatments in urease activity were very low, especially in sandy and calcareous soils. Ammoniacal nitrogen in soils amended with urea increased markedly in loamy and alkali soils one day after application, followed by gradual decrease. The decrease in NH 3 -N was associated with concomitant increases in NO 3 -N in different treatments. The increase in NO 3 -N, attributed to urea amendment, falls in the following descending order: loamy, saline, alkaline, sandy, and calcareous soils. This could be attributed to the high volatilization of NH 3 in alkali, sandy, and calcareous soils.

Application of the fluorescence-recovery after photobleaching (FRAP analysis) technique and scrape loading/dye transfer assay was made to measure the presence of gap junctional communication in primary rat glial cells in vitro in the presence and absence of the neurotoxicant and tumor promoter dieldrin, a chlorinated insecticide. Results demonstrate that primary rat glial cells are able to exhibit gap junctional intercellular communication and that dieldrin at noncytotoxic concentrations can modulate gap junctional communication as early as 10 min after exposure to the chemical and that the effect is reversible after 4 hr recovery from the dieldrin exposure. Both the FRAP analysis and the scrape loading/dye transfer assay have validated the observation that dieldrin inhibits gap junctional communication in other cell types using different techniques to measure gap junction function. These results were interpreted as an indication that inhibition of gap junctional communication might contribute to the cellular mechanism of dieldrin's neurotoxicity.

Summary In pot experiments, urea was applied to different Egyptian soils at a standard rate of 150 kg/fed. at different depths, namely at 0, 0.5, 1.0, and 2.0 inches below the surface of the soil. Moisture content was kept constant in all treatments so that the only variable factor was the depths of application. Representative soil samples were taken at intervals of 1, 3, 7, 14, and 28 days. They were periodically analysed for total microbial counts, urease activity, ammoniacal and nitrate nitrogen. Results can be summarized as follows: 1 The highest microbial densities were generally achieved when urea was mixed with the soil or laid at 2 inches depth. In calcareous soil, however, mixing urea with the soil gave the best result in this respect. Spreading urea on the surface of different soils gave the lowest microbial size during the experimental periods. 2. Urease activity was not appreciably affected with the depth of urea application. However, when urea was mixed with the soil, the highest urease activity was generally achieved. 3. NH3-N in loamy, saline, and alkaline soils showed no clear differences due to application of urea in different dephths. In sandy soil, however, mixing urea with the soil gave the highest values of NH3-N during the experimental period, followed by 2 inches depth application. In calcareous soil, either mixing or laying urea in 2 inches depth gave the highest values of NH3-N. In general, when applied on the surface, the lowest values of NH3-N were observed in all soils. 4. NO3-N in alkali and calcareous soils showed the highest values when urea was mixed with the soil. In the rest of the soils, application of urea either at 2 inches depth or mixed with the soil gave the highest values of NO3-N. Application of urea on the soil surface gave the lowest values in all the soils. This may be due to the high volatilization rate of ammonia in such treatment.

Gap junction-mediated intercellular communication has been recognized in cells from different tissues of various organisms and has been implicated in a variety of cellular functions and dysfunctions. Here we describe a new, direct and rapid technique with which to study this cellular phenomenon. It employs scrape-loading to introduce a low molecular weight (MW) fluorescent dye, Lucifer yellow CH (MW 457.2) into cells in culture and allows the monitoring of its transfer into contiguous cells. In communication-competent cells the dye transmission occurred within minutes after loading. The involvement of membrane junctions in Lucifer yellow transfer was verified by the concurrent loading of a high MW marker dye conjugate, rhodamine dextran (MW 10,000). Once introduced intracellularly the rhodamine dextran is unable to cross the relatively narrow membrane junctions. Chemicals of variable potency known to block junctional communication were tested in Chinese hamster V79 cells and other mammalian cells. The results showed effective blockage of the dye transfer at non-cytotoxic doses. This new technique can be applied to a wide variety of mammalian (including human) cells. In addition, it has the potential to be utilized as a rapid screening assay to detect chemicals that can modulate intercellular communication and to study their mechanism of action.

Inhibition of intercellular communication has been hypothesized to play a role in tumor promotion. The compound 2,2',4,4',5,5'-hexabromobiphenyl (245-HBB) is a tumor promoter in vivo and blocks intercellular communication in vitro. The scrape-loading/dye-transfer (SL/DT) assay was used to assess this in vitro effect at varying concentrations of 245-HBB. The SL/DT technique is based on the intracellular loading of a fluorescent dye, lucifer yellow (LY), and monitoring its transfer into adjacent cells via patent gap junctions. Confluent WB-F344 (rat epithelial) cells were exposed to various noncytolethal concentrations of 245-HBB. Transfer of LY was then quantified with anchored cell analysis/sorting (ACAS 470, Meridian Instruments, Okemos, Mich.). The results indicate an inverse correlation between the degree of fluorescence in secondary LY-recipient cells and the treatment concentration. The coupling of these two new methods of cellular biology provided rapid quantitative analysis of dye transfer in measuring the concentration/response of modulation of gap-junctional permeability in cultured cells.

The effect of composition on amorphous chalcogenide threshold switches of the system SixTe60-xAs30Ge10, wherex = 5, 10, 12 and 20, has been studied. The compositionx = 5 shows the best switching characteristics, e.g. the smallest holding voltage (Vh = 0.4V), the highest ON state current (Ih = 45μA) and smallest threshold voltage (Vs = 1.5V). Applying the three mechanisms of conductance of Mottet al. (Phil. Mag.37 (1975) 961), it is found that for a particular compositionσ2

Summary Vicia faba seeds treated with CCC and germinated under different temperatures showed different responses on germination rate, germination percentage as well as radicle and plumule lengths. CCC exhibited a stimulating effect on germination and plumule lenght at 10 °C.

Summary The presence of NaHCO3 in the nutrient solution caused a decrease in the chlorophyll a, b and protein -N content in the leaves of cotton plants. Under such conditions P32 uptake was also decreased and accumulated in the roots. Spraying the plants, which fed with NaHCO3 with CCC induced an increase in chlorophyll a and b as well as protein-N contents as compared with the unsprayed plants. This treatment seemed to mobilize the accumulated P32 in the root towards the leaves. It was suggested that CCC could overcome the negative influence of NaHCO3 on photosynthetic apparatus and the utilization of P32 within the plants.

Field experiments in two successive seasons (1971–1972) were carried out to examine the effect of spraying table beet plants with chlormequat (CCC) on their growth and yield. Concentrations used were 500 and 1000 ppm. Spraying in the first season was carried out 60, 75 or 90 days after sowing. According to the result of the first season, which showed no significant differences according to varying spraying date, only one spraying time was chosen for the second season (75 days). In both seasons, CCC exhibited modifications in growth and increased root yield significantly. Number of leaves and their dry weight per plant were increased. The increases in leaves dry weight per plant was found not to be a result of the increase of leaves number per plant only, but the leaves dry weight percentage was also increased Root length showed insignificant increases due to CCC treatment. In the same time, significant increments in its diameter as well as in dry weight per plant were recorded in both seasons, which might be the cause of increasing yield. Ratio of leaves/roots (dry weight) was shifted in the treated plant towards the root side.

The effects of CCC on the 32 P amounts absorbed by cotton seedlings were studied. CCC was applied to the seedlings either as spray or as addition to the nutrient solution in concentrations of 0, 25, 50, 100 and 200 mg/1. 32P was added to the medium as KH232P O4 in the concentration of 40 μCi/50 ml. During the experimental period, no morphological changes were observed. The total 32P uptake was inhibited in CCC treated seedlings. The application of CCC, both as spray and as addition to the medium, led to an accumulation of 32P in stem, but to a decrease in root. The leaves showed different responses to different methods of application; spraying increased, while an addition of CCC to the medium decerases the 32P content in the leaves. It is concluded that CCC inhibits 32P uptake, whereas it ac accelerates the 32P translocation from root to the aerial parts.

Two experiments, one in the summer and one in the winter season, were conducted under field conditions to study the effect of CCC3 on the growth and yield of potatoes. CCC was sprayed at two different times (49 and 64 days after planting) with different doses (500, 1000, 2000 g active ingredient/ ha). Stem height was depressed proportionately to the dose applied. Dry matter content of leaves, of total foliage, as well as of tubers per plant showed increases during growth due to some treatments. Total tuber yield was also increased.

Summary Plants treated with CCC had higher contents of total chlorophyll, chlorophyll (a) and carotenoids. Spraying the CCC treated plants with GA decreased the total chlorophyll, chlorophyll a, and chlorophyll b as well as carotenoids content. Plants treated with GA showed a decrease in total chlorophyll and chlorophyll b content. Spraying the GA-treated plants with CCC increased the total chlorophyll and chlorophyll a contents. These treatments had no significant effect upon carotenoids content. It was concluded that CCC and GA act on chlorophyll content through different mechanisms.

Cotton plants grown under water stress conditions showed significant decreases in yield, though only slight decreases in protein N as well as in chlorophyll content were detected. Chlormequat (CCC) application minimized the decreases in yield and caused significant increases in both protein N and chlorophyll contents. It is concluded that changes induced by CCC in cotton yield are independent from those occurred in chlorophyll and protein N contents.

The influence of manganese on the vitamin-C content of some culture plants grown in water cultures was examined. Ascorbic acid (AS) and dehydroascorbic acid (DAS) were determined by Tillmanns method. The AS-content shows an increase due to manganese nutrition but there is no influence on the total vitamin-C content (AS + DAS).

Wheat plants sprayed with chlormequat chloride (CCC) at concentrations of 4 and 8 1/ha overcame lodging and plant heights were decreased owing to the shortening of the upper internodes. Grain yield increased significantly in plants treated with 2,4 and 81/ha. Number of ears/plant was also increased, but neither the length of ear on the main stem nor the weight of 100 grains was affected by CCC. In addition, sometimes the number of grains/ear increased. The increase in yield is attributed to more fertile tillers/plant and/or to more grains/ear.

The changes in cottonseed constituents at different boll ages ranging from 5 to 60 days after flowering are reported. A gradual depletion of sugars coincided with gradual formation of oil has been found. Proteins are accumulated at a more or less even rate. Gossypol starts its appearance in 10 days old boll, and continuously increases. The iodine value of the oils shows gradual increase, while the acid value continuously decreases. Continuous decrease in total saturated fatty acids during development and maturity was observed while linoleic acid continuously increases. The total phospholipid content of the oil continuously decreases. The total saturated fatty acid contents of the phospholipids are generally higher than that of their corresponding oils.

Yields of field beans are very unreliable, ranging sixfold under given climatic conditions (23).

Treating soyabean plants with chlormequat chloride or N-dimethyl-N-(β-chloroethyl) hydrazonium chloride in concentrations of 50–400 ppm at two different growth stages did not affect the content of the different N-fractions or of oils in the seeds obtained. Some treatments led to small increases in total carbohydrate content.

The following substances, which occur naturally in plants, do not interfere with the titration of ascorbic acid with 2, 6-dichlorophenolindophenol (DIP): reduced glutathione, cystein, pyrogallole, brenzcatechin, hydrochinone, tannin, glucose and fructose. This is also true for the titration with DIP of high unphysiological concentrations of these substances dissolved in HPO3 solution.