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A series of nine new 2,3-disubstituted 4(3H)-quinazolin-4-one derivatives was furnished starting from the 2-propyl-4(3H)-quinazo-line-4-one (2). The reinvestigation of the key starting quinazolinone 2 was performed under microwave irradiation (MW) and solvent-free conditions. Combination of MW and phase-transfer catalysis using tetrabutylammonium benzoate (TBAB) as a novel neutral ionic catalyst was used for carrying out N-alkylation and condensation reactions of compound 2 as a simple, efficient and eco-friendly technique. The structure of the synthesized compounds was elucidated using different spectral and chemical analyses. In vitro antimicrobial activity of the compounds was investigated against four bacterial and two fungal strains; very modest activity was achieved. Some of the synthesized compounds were screened for their antitumor activity against different human tumor cell lines. The screened compounds exhibited a significant antitumor activity on some of the cancer cell lines, melanoma (SK-MEL-2), ovarian cancer (IGROV1), renal cancer (TK-10), prostate cancer (PC-3), breast cancer (MCF7) and colon cancer (HT29). The most active, even more active than the reference 5-fluorouracil, were found to be ethyl 4-[(4-oxo-2-propylquinazolin-3(4H)-yl)methyl]benzoate (3c), 3-{2-[6-(pyrrolidin-1-yl-sulfonyl)-1,2,3,4-tetrahydroquinoline]-2-oxoethyl}-2-propylquinazolin--4(3H)-one (3e), N’-[(E)-(2H-1,3-benzodioxo-5-yl)methylidene]-2-(4-oxo-2-propylquinazolin-3(4H)-yl)acetohydrazide (10a), N’-[(E)-(4-hydroxyphenyl)methylidene]-2-(4-oxo-2-propylquinazo-lin-3(4H) -yl)acetohydrazide (10b) and N’-[(E)-(4-nitrophenyl)methyl idene]-2-(4-oxo-2-propylquinazolin-3(4H)-yl)acetohydrazide (10c).

Medicinal plants have been widely used in folk medicine. They are considered today as an interesting source of new drug due to their bioactive components. The genus, Cymbopogon (Poaceae) seems to be the most promising source of several bioactive compound. This study aimed at evaluating the antimicrobial activities of Cymbopogon schoenanthus on several pathogenic bacteria, fungi and virus. Antibacterial and antifungal activities were evaluated using the agar well diffusion methods. The MIC was determined by micro-broth dilution methods. The cytotoxicity of C. schoenanthus extracts was evaluated using MTT assay. The results showed that methanol extract of C. schoenanthus exhibit an antibacterial effect on several Gram-positive and negative bacteria. All extracts tested (aqueous extract, methanol extract and ethyl acetate extract) were found to have an antiviral effect on HSV1; whereas, no antifungal effect was detected on both Candida albicans and Aspergillus niger. Key words: Antiviral, antibacterial, bioactive properties, Cymbopogon schoenanthus, medicinal plant.

Enhancement of absorption and extending its bandwidth is of major interest for solar cells, photodetectors, and variety of applications. This paper presents a nano-structure formed of an array whose elements are in the form of a 3X3 cluster of metal rings having a similar outer diameter but with various inner diameters. Thus, each ring size produces certain resonance frequency and the result of the cluster arrangement is staggered responses that possess larger bandwidth. Simulations using the periodic unit cell approach and the CST microwave studio suite showed that the average absorption power in an amorphous silicon layer has been improved by 3.32 times compared to that without rings. The obtained response covers the frequency range from 230 THz to 360 THz.

In addition to its nutritive value, there are ample studies regarding the me-dicinal properties of the mushroom Pleurotus ostreatus fruit bodies. Howev-er, finding such medicinal activities from submerged mycelium culture will be of considerable interest. The present study aimed to determine the antioxidant and immunomodulating activities of P. ostreatus mycelial extract. The scavenger activity was determined using DPPH, while the im-munomodulating activity was determined by measuring the in vitro prolifer-ative capacity of murine splenocytes as well as the phenotypic and matura-tion of bone marrow dendritic cells (BMDCs). The present results showed increases in the scavenging activity of P. ostreatus mycelial extract compared to ascorbic acid control group, and increases in the proliferative capacity of murine splenocytes compared to vehicle control, except with the higher con-centration. In addition, BMDCs stimulated with P. ostreatus mycelial extract elicited increases in surface expression of CD11c+and CD80, suggesting that P. ostreatus treatment directly induces BMDCs to mature. These results re-vealed considerable antioxidant and immunomodulating effects of P. os-treatus mycelium suggesting its potential application as an immunomodu-lating agent in pharmaceutical, nutritional complement and even medical studies.

Nanoantennas are suitable components for detection of optical radiation at energies below the bandgap energy of the semiconductor and higher than Schottky barrier of metal/semiconductor interface in photodetectors. Elliptical nanodisk antennas (ENAs) on a Gallium Arsenide (GaAs) substrate are studied to tune the optical response across the near-infrared band. The resonance wavelength, normal field enhancement, and bandwidth of plasmonic resonance are tailored by controlling the size and elliptical aspect ratio. The results are compared with circular nanodisk antennas (CNAs) and ring nanoparticle antennas (RNAs). Silver and gold metal types for nanoantennas are also studied for electric field enhancement, where the Drude model of metals are considered. The surfaces plasmon is proven by comparing with the perfect electric conductor of silver and gold nanoantennas. The obtained results prove that the designed nanoantennas can be used to enhance the operation of photodetectors and solar cells.

Labiatae family is represented in Saudi Arabia. The aim of the present study was to go insight to investigate the anticancer activity and antioxidative potentials of methanolic extracts of Mentha longifolia L. (ML) and Ocimum basilicum L. (OB) that grown in Madina province, western region, Saudi Arabia. OB exhibited the greater phenolic contents as mg gallic acid equivalent/g weight (mg GAE/g) for a value of 105 +/- 5.5 mg GAE/g. On the other hand, ML produced 29 +/- 3.12 mg GAE/g. The standard antioxidant vitamin E used in this experiment elicited a value of total phenolic contents equal 22 +/- 2.2 mg GAE/g. The percentage scavenging activity of against diphenylpicrylhydrazyl (DPPH) was 850 and 160% for OB and ML extracts, respectively. Vitamin E elicited% scavenging activity of against DPPH equal to 198%. Brine shrimp cytotoxic assay clearly indicated the cytotoxic effects of either ML or OB extract. The brine shrimp survival is inversely proportional to the concentration of either ML or OB extract used with LD50 191.23 and 235.50 ppm, respectively. Toxic effects on brine shrimps indicated the anticancer potential of ML or OB extract. The ML or OB extract was unable to produce pbluescript (pBS) plasmid DNA damage, while the plasmid DNA treated with EcoRI produced a single band as a result of DNA damage. Also, both ML and OB extract exhibited marked cytotoxic activity against MCF-7 cells at various concentrations (20, 40, 80, 160 and 320 microg mL(-1)). The 160 and 320 microg mL(-1) showed more cytotoxic effect against MCF-7 cells. Based on results achieved, we can concluded that, OB and ML extracts have the potency to act as powerful antioxidants and protect against DNA damage and have cytotoxic activity against MCF-7 cell line.

Properties of Gaussian like orbital wave function and Slater like orbital wave function for Helium atom and Helium like ions was studied. This included energy, the radial distribution function, the shape of the wave function near the nucleus and the orbital exponent. For Gaussian the values of the orbital exponent and the constants varied using linear combination of four Gaussian functions to approximate the radial component of atomic orbital, the obtained result is better than universal result. Theory

The purpose of this work is to examine five trial wave functions for the helium atom and the helium-like ions (He, Li+, Be2+,…..Ne8+). The comparisons between the trial wave function have been done in view of the calculated energy (E) and the electron–electron repulsion, \( \left\langle {\frac{1}{{{r_{12 }}}}} \right\rangle \), for the atom and all the ions considered. The calculations show that as the wave function becomes more correlated, E corr increases and the percentage error in energy calculation decreases, whereas this percentage, for all systems under study, decreases as Z increases. The best trial wave function in this work gives results closer to the experimental findings due to a reduction in electron–electron repulsion.

Ebullient gases from Michigan wetlands have been collected and analyzed to deduce in situ methane fluxes. Methane flux has been found to be a function of mean air temperature. This relationship has been utilized to extrapolate observed methane fluxes to estimates of fluxes from the Pripet marshes, Sudd, Everglades, and Ugandan swamps. These four wetlands together provide a yearly source of 6.8 × 10 13 g of methane to the atmosphere. DOI: 10.1111/j.2153-3490.1977.tb00731.x

In order to understand the molecular mechanisms of longevity regulation, we recently performed a screen designed to enrich for genes common to several longevity interventions. Using this approach, we identified the Drosophila melanogaster gene takeout. takeout is upregulated in a variety of long-lived flies, and extends life span when overexpressed. Here, we investigate the mechanisms of takeout-dependent longevity. takeout overexpression specifically in the fat body is sufficient to increase fly longevity and is additive to the longevity effects of Dietary Restriction. takeout long-lived flies do not show phenotypes often associated with increased longevity, such as enhanced stress resistance or major metabolic abnormalities. However, males exhibit greatly diminished courtship behavior, leading to a reduction in fertility. Interestingly, takeout contains a binding domain for Juvenile Hormone, a fly hormone that plays a role in the regulation of developmental transitions. Importantly, the longevity and courtship phenotypes of takeout overexpressing flies are reversed by treatment with the Juvenile Hormone analog methoprene. These data suggest that takeout is a key player in the tradeoff-switch between fertility and longevity. takeout may control fertility via modulation of courtship behavior. This regulation may occur through Juvenile Hormone binding to takeout and a subsequent reduction in Juvenile Hormone signaling activity.

The radial and electronic correlation effects for intra-electronic shell have been examined within two-electron system, helium atom, and compared with two helium like ions, Li+ and Be++ using the uncorrelated Hartree Fock wave function published by Clementi and Rotti (At Data Nucl Data Tables 14:177, 1974) and the correlated configuration interaction wave function published by Weiss (Phys Rev 122:1826, 1961). Some atomic properties have been studied to exam the radial correlation effects such as; (i) one-particle radial distribution function and one-particle expectation value when k=−2 to 2, (ii) two-particle radial distribution function and two-particle expectation value when k=−2 to 2, (iii) the inter-particle distribution function and inter-particle expectation value when k=−2 to 2, and, (iv) the partial distribution function. In addition to these atomic properties, coulomb hole, partial coulomb hole, the radial correlation for one and two-particles distribution function and the radial correlation energy are very important in studying the physical and chemical properties of these ions or atoms. The results were compared with that calculated in previous published work using partitioning technique.

Three biosensor configurations that included a dissolved oxygen electrode and yeast cells (Saccharomyces cerevisiae) were evaluated as a means to assess the environmental effects of toxic chemicals. The configurations were: closed suspension—assay medium closed to air and cells suspended in the medium; open suspension—assay medium open to air and cells suspended in medium; and biofilm electrode (BFE)—assay medium open to air but cells immobilized on the surface of the electrode. The BFE was the most advantageous configuration based on assay times and detection limits.

There are often difficulties in estimating the bioavailability of essential nutrients and energy sources for aquatic microorganisms involved in mediating key sedimentary biotransformations. In order to estimate rates of sulfate reduction and putrefaction in sedimentary hydrogen sulfide production, a kinetic bioassay procedure was utilized to confirm the concentrations of hydrogen sulfide precursors determined by standard analytical procedures. Results were suggestive but inconclusive that sulfide production via sulfate reduction and putrefaction adhere to the Michaelis-Menten kinetic model. Nevertheless the kinetic bioa_s~y procedure of Wright and Hobble (Ecology 47, 447-464, 1966) appears to be useful in estimating substrate bioavailability for cysteine and sulfate and perhaps other sedimentary substrates. In addition the method described permits reliable tracer estimates of sulfide production in freshwaters with low sulfate concentrations which might otherwise not be possible.

A biosensor electrode system with unique configuration and a thin layer of immobilized yeast cells, set on the surface of an amperometric oxygen membrane electrode, was developed for rapid screening of toxic chemicals in a variety of pollution and process control applications. Measurement is based on the instantaneous detection of changes in oxygen respiratory activity of biofilm of yeast cells upon exposure to toxic chemicals. The design of this electrode system, referred to as biofilm electrodes, was based on a mathematical model of oxygen transport in the biofilm and the electrochemical current response. The biofilm, which consists of three sublayers—boundary layer, filter pad, and yeast cell layer—was modeled as a one composite diffusion layer, or three separate layers in series. While the three layer model is more theoretically complete, the one layer model was more reliable and simpler to use.

In a full scale experimental study, raw sewage from the City of Suez, Egypt was treated using a stabilization pond system. Fish grown in the treated sewage was compared with fish from one of the farms which receives contaminated surface water in Lake Manzala. Organochlorine pesticides were detected at higher levels in fish from Lake Manzala farms, than in fish reared in the treated sewage of the City of Suez. The highest levels were due to p,p'DDT and its metabolites, followed by Lindane and HCB. Furthermore, the concentrations of Pb and Cd were significantly higher in the fish from the Lake Manzala farm, than in the fish from Suez. In addition, the concentration levels of Pb and Cd in the fish from Lake Manzala exceeded the international contaminant limits for human consumption. In general, fish grown in this region have high levels of pesticides and metal contaminants. It is interesting to note that in spite of possible cultural bias against fish grown in treated sewage effluents, have lower levels of toxic chemicals than some of the marketed fish, harvested from polluted surface waters.

The need exists for rapid and inexpensive methods to determine the health effects of environmental contaminants on biological systems. One of the current research approaches for assessing cytotoxicity is to monitor the respiratory activity of the mitochondrion, a sensitive, nonspecific subcellular target site. Detected changes in mitochondrial function after the addition of a test chemical could be correlated to toxic effects. Mitochondrial respiration can be characterized by three indices: state 3 and state 4 respiratory rates, and the respiratory control ratio (RCR). State 4, the idle or resting state, results when coupled mitochondrial respire in a medium containing inorganic phosphate and a Kreb's cycle substrate in the absence of a phosphate acceptor such as adenosine diphosphate (ADP). In the presence of ADP the respiration rate increases to a maximum (state 3), accompanied by phosphorylation of ADP to adenosine triphosphate (ATP). The ratio of state 3 to state 4, or RCR, indicates how tightly the oxidative phosphorylation process is coupled. The synthesis of ATP by mitochondria is influenced by a number of compounds, most of which are either uncouplers or inhibitors.

Differential pulse polarography and differential pulse anodic stripping voltammetry were used to determine copper, lead, cadmium and zinc complexes of relevance to environmental conditions. The dependency of peak current on pH and alkalinity was interpreted in terms of the variation in the metal species present. Stability constants of copper and lead complexes with carbonate were determined from the magnitude of the shift of peak potential using the method of Lingane. Inclusion of the transfer coefficient, calculated from the peak half-width for electrochemically irreversible systems, was used to determine the stability constant. By using both electroanalytical techniques, the investigator validates the correctness of his results without needing to rely on prior determinations of the stability constant for verification.

A method for determining carboxylic acids and phenols from aqueous solution is described. Trace concentrations in the parts per billion levels of these pollutants are determined. This is accomplished by a concentration step using macroreticular resins with pyridine elution, subsequent derivatization with Bis-trimethylsilyl acetamide (BSA), and analysis by gas chromatography. The method gives good recovery for several phenols and acids of environmental importance.

Non-steady state voltammetry has been applied to membrane electrodes to provide improved sensitivity as well as independence of stirring. This paper describes a new instrumentation system based on complementary metal oxide—silicon technology for the characterization of a pulsed oxygen electrode. The system provides the necessary timing, analog-to-digital conversion, and digital display of the transient current.

An automated system for the analysis of dissolved organic nitrogen has been developed and applied to natural waters. It is based on subjecting sample to u.v. irradiation followed by a heterogeneous reduction of the nitrogen containing irradiation products to ammonia which is detected by an ammonia gas sensing probe. Quantitative recoveries of different organic nitrogen compounds common to natural waters were obtained after 17 min of irradiation. Determination with and without irradiation make possible the separate determination of total and inorganic nitrogen, respectively.

The differential pulse polarography of phenyl arsenoxide (C6H5AsO) and its use in the indirect determination of chlorine and ozone is described.

The effect of pH and hardness metal ions on the interactions between trace metals and both inorganic and organic complexing agents has been studied under conditions simulating natural aquatic conditions, by employing anodic stripping voltammetric titration techniques. The complexation of Bi(III), Cd(II), Cu(II), Pb(II), and Tl(I) with the hydroxo- and carbonato-ligands found in a carbonate medium has been observed to generally increase with increasing pH. Both labile and nonlabile interactions have been observed. Nonlabile interactions are predominant at low pH and labile interactions generally increase with increasing pH. Neither calcium nor magnesium affects these interactions. The complexation of humic acids with trace metals in a carbonate medium was found to be more intense than metal ion-inorganic complexation. Both labile and nonlabile complexation was found; however, no generalizations can be made concerning the type and extent of complexation because of the individual nature of the interactions of each trace metal. Calcium was found to be more effective than magnesium in inhibiting trace metal-organic complexation. The effect of calcium is to inhibit labile complexation and is most pronounced with the cadmium-humic acid system.

A voltammetric membrane electrode system has been modified and applied to the in situ measurement of chlorine dioxide. The electrode system consisted of a gold cathode, a silver/silver chloride reference electrode, and a gold counter electrode. Different membrane materials were tested; silicone rubber polymeric membranes were found to be most suitable. Electrode applications involved the use of both steady state and pulse voltammetric techniques. Pulse voltammetry was primarily used for trace analysis since the sensitivity observed was about 4200 times greater than under steady state conditions. This electrode system will find its widest application in water supply disinfection processes using chlorine dioxide. It offers the unique advantage of being sensitive to gaseous chlorine dioxide and not to oxychlorineions. Chlorine dioxide is a much more powerful disinfectant than oxychlorineions. Furthermore, the electrode system can be used forinsitumon it oring of C102 levels and the automatic control...

Methane biosynthesis within the anaerobic ecosystem results from the diphasic conversion of complex organic substrates through a series of biologically mediated oxidation-reduction reactions which arc pH dependent. Routine parametric analysis of the products emanating from the corresponding acid and methane fermentation phases of the anaerobic digestion process provide a basis for determination of process condition and efficiency. Of these analyses, pH and electrode potential of pE are intensive parameters of considerable significance but for which interpretation is often difficult and misleading. Attention has been focussed on the analogy and distinction between pH and pE determinations and their application to the anaerobic ecosystem. Theoretical and practical limitations are discussed and experimental evidence presented which supports the possible use of pH and pE determinations for process evaluation and control.

Although the concentration of soluble organic phosphorus in lake water often exceeds that of orthophosphate severalfold, little is known of its composition. By using enzyme assays it was determined that up to 50 percent of the organic fraction is hydrolyzable by phytase. The enzymatically degradable material consists of both low and high molecular weight fractions.