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This paper presents a sparse quaternion‐valued minimization (SQVM) based control technique of a two‐stage grid supportive photovoltaic (PV) power system with power conditioning capabilities. The grid side converter (GSC) is controlled by utilizing an SQVM control technique. The proposed algorithm enables the GSC to mitigate the load harmonics current and provides reactive power compensation at the point of common coupling (PCC). The proposed control is tuned to mitigate the DC offset error, harmonics current and to improve the frequency response of the proposed system. A DC link pre‐predictive is incorporated to improve the dynamic response by reducing the burden on the outer Proportional‐Integral (PI) voltage controller loop. Further, it is used to extract the fundamental component of load currents for generating the reference currents. An adjustable DC link voltage loop is incorporated in the proposed control technique to adapt the PCC voltage variation, which helps in minimizing the losses of the PV system. For real‐time execution of the adjustable DC link voltage concept, the DC link voltage is adapted with a variation in the PCC voltage. The operation and control of the system topology are validated experimentally under various scenarios.

End-stage renal disease and its treatments negatively affect quality of life. Self-care is an important approach for helping the patients deal with their problems. The aim of this study was to improve self-care and quality of life of haemodialysis patients through teaching and evaluating their quality of life. This cross-section design with pre-post assessment was conducted in the dialysis unit of Suez Canal University Hospitals, participants were 50 patients receiving maintenance haemodialysis. Data were collected using a structured interview questionnaire, and the Kidney Disease Quality of Life Scale Short Form. Statistically the results show significant improvements that were revealed in the scores of many domains of quality of life, p < 0.001, except the physical domain. Statistically significant associations were revealed between pre- and postprogramme improvement in the total quality-of-life scores. The statistically significant independent predictors of quality-of-life improvement were programme attendance, dialysis duration and marital status.

The purpose of this work was to study the effects of adding different concentrations of iron (Fe), manganese (Mn) and zinc (Zn) in irrigation water to high-pH sandy soil on the growth and micronutrient uptake of sunflower plants (Helianthus annus L., cv. Giza 1). The experiment was carried out in Mitscherlish pots under greenhouse conditions. Low Fe, Mn and Zn concentrations were found to have a positive effect on the micronutrient contents of the plant organs. The number of leaves and the leaf area were increased by addition of Fe, Mn and Zn. Root size was increased by addition of Fe and Mn. Stem and root lengths were increased by Mn only. It could be concluded that continuous addition of Fe, Mn and Zn in irrigation water to high-pH sandy soil deficient in these nutrients, where root growth was contained within a limited volume (in pots), led to increases in growth and micronutrient uptake (Fe, Mn and Zn). Further studies are needed to determine whether similar effects will be found under field conditions.

Exposure to specific halogenated aromatic hydrocarbons (HAHs), such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), can produce a wide variety of species- and tissue-specific toxic and biological effects. The presence of HAHs in environmental samples as complex mixtures has made it difficult to predict the biological and toxic potency of these chemicals. The authors have used aspects of the molecular mechanism of action of these chemicals to develop a species-specific bioassay system for detection of bioactive HAHs in complex mixtures. Here they describe construction and utilization of a recombinant expression vector that responds to these HAHs with the induction of an easily measurable gene product, heat-stable human placental alkaline phosphatase (PAP). This vector contains the PAP gene under TCDD-inducible control of four dioxin-responsive DNA enhancer elements. HAH-inducible expression of PAP from the recombinant vector occurs in a dose- and Ah-receptor- (AhR-) dependent manner. Stable transfection of this vector into mouse hepatoma cells has produced a novel cell line in which AhR-dependent induction of gene expression can easily be measured. This transfected cell line can readily be used for detection and relative quantitation of AhR agonists in complex mixtures of environmental and biological samples and for identification and characterization of novel AhR agonists.

A term white girl presented with low birth weight, minor anomalies, and congenital heart defects. The infant had microcephaly, upslanting palpebral fissures, prominent nasal bridge, short philtrum, thin upper lip vermilion, down-turned corners of the mouth, receding mandible, and short broad neck. The hands showed proximal placement of the thumbs, bilateral clinodactyly of the index finger, and bilateral transverse crease. Both hands were clenched, with the index finger overlapping the third finger and the fifth finger overlapping the fourth. There was also talipes calcaneo-valgus, bilateral dorsiflexion of the metatarsophalangeal joints, flexion of the interphalangeal joints, and hypoplasia of all nails. The patient's karyotype was 46,XX,-22, + der(9)t(9;22)(q21.13;q12.1)mat; the mother had the balanced translocation 46,XX,t(9;22)(9pter----9q21.13::22q12.1----22qter++ +;22pter---- 22q12.1::9q21.3----9qter). The infant died at age 10 days, and the autopsy showed absent thyroid isthmus and rudimentary thymus, with one small ectopic parathyroid attached to it. The lungs were hypoplastic, with abnormal lobation. The cardiac anomalies included truncus arteriosus, truncal valve stenosis, single carotid trunk, subclavian arteries arising from the distal part of the aortic arch, atrial and ventricular septal defects, right ventricular hypertrophy, and a hypoplastic left pulmonary artery. Also, multiple small accessory spleens were present in addition to a normal-sized spleen. This case combines features associated with DiGeorge anomaly and dup(9p). The chromosome abnormality in this patient appears to have arisen in a maternal germ cell due to adjacent type II disjunction.

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.

A pot and 2 successive seasons field experiments were conducted on bean, by spraying 25,50 or 100 ppm GA, 100, 250 or 500 ppm of either CCC or B-9, one month after sowing. Results showed that: GA induced stem elongation and thinning through cell elongation and decrease of both of ground tissue cell-size and vascular cylinder cell layers in the stem. On the other hand, CCC and B-9 led to stem shortening and thickening, as a consequence of increased number of cell layers leading to widening the vascular cylinder of the stem. Leaf area was much more increased by CCC and B-9 than by GA. GA increased amylase activity and had no effect on invertase, meanwhile CCC and B-9 mostly decreased the former's and increased the latter's enzyme activity, 30 days after spraying. GA and CCC increased number of seeds/pod, while B-9 had no effect on this character. CCC and B-9 increased pod number/plant, specific seed weight, leading to increment of seed yield/plant, while GA had no effect on these characters.

Measurements are made of the electrical conductivity (σ) of glasses in the system As2SexTe3-x at low fields (F) down to about 104 Vm−1, and at high fields up to more than 108 Vm−1 for various ranges of temperature (T) above and below room temperature! σ increases with F and T. Graphs of σ versus F show a finite, non-zero slope as F tends to zero for each material measured. The slope of In (σ) versus F remains the same for individual materials up to values of F between 107 and 108 Vm−1; at some value of F in this range the slope often increases quite abruptly. The value of F at which the slope becomes steep, is approximately proportional to the energy gap of the material. Because of this result it is suggested that the effect may be due to excitation of electrons from the valence band to the conduction band states (ionisation by impact); there is some other evidence to support this suggestion. However, other features of the results seem to be consistent with an explanation based on the Poole effect. The behaviour of σ is generally consistent with the equation σ = σc exp (F/F0) exp (-U/kT). On a mesure la conductivite electrique (σ) des matieres vitreuses au systeme de As2SexTe3-x aux champs (F) faibles et champs eleves de 104 Vm−1 a plus de 108 Vm−1 pour les temperatures audessus et au-dessous de la temperature de la salle. σ s'accroit avec F et T. Les abaques de σ contre F se laissent voir une pente, non-zero, quand F s'approache de zero pour chaque matiere mesuree. La pente de ln (σ) contre F est la měme pour chaque matiere seule aux valeurs de F entre 107 et 108 Vm−1; ici les courbes se redressent plus rapidement. La valeur de F, a laquelle la pente se fait rapide, est proportionnelle approximativement a la largeur de la bande interdite de le matiere. A cause de cet resultat on propose que l'effet est cause de l'ionisation par le choc; il y a d'autre evidence qui soutient cette idee. Quoi qu'il en soit, des autres traits des resultats semblent s'accorder avec une explication fondee sur l'effet de Poole. En general l'equation σ = σc exp (F/F0) × x exp (-U/kT) a ete confirmee experimentalement.

The modulation of gap junctional intercellular communication (GJIC) plays an important role during tumor promotion. Several tumor-promoting agents are known to inhibit this form of cellular coupling. In addition, tumor cells and cells expressing certain oncogenic products have been shown to exhibit inhibited or reduced GJIC. The Ha-ras oncogene is expressed in a wide variety of human tumors from different tissues. Its p21 product is a membrane-bound polypeptide, the function of which is not fully characterized. We tested the effects of the expression of the human c-Ha-ras-1 oncogene, derived from the EJ/T4 bladder carcinoma cell line, on the ability of the Chinese hamster V79 cells to conduct gap junctional communication. The junctional competence was studied by two different methods, the scrape-loading/dye transfer technique and the metabolic cooperation assay. The results indicate a strong correlation between the expression of p21 ras protein and the inhibition of gap junctional function. Assuming that reversible inhibition of intercellular communication plays a role during tumor promotion and stable inhibition during the tumor progression phase of carcinogenesis, our data suggest that, while chemical tumor promoters and the ras oncogenes might work by different biochemical mechanisms, they both affect a critical cellular function; namely, GJIC.

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.

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.