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Fungi, molds, and algae are abundant in the environment, leading in many cases to different types of infections and diseases, such as immune suppression/reduced immune function, respiratory diseases, allergies, asthma, and superficial and subcutaneous infections (skin, keratinous tissues, and mucous membranes), among others. These organisms infect billions of people and cause millions of deaths worldwide, putting a massive and costly strain on healthcare systems. As such, there is an urgent need to develop safe and cost-effective continuous self-sterilizing systems to prevent bacterial and viral infections. Apart from polymeric or metallic systems, photocatalytic systems are currently being investigated, in particular photo-self-cleaning materials made of silver nanoparticle (AgNP)-doped titanium dioxide (TiO2). This chapter evaluates the photoactivity of commercial AgNP-doped TiO2 Porcelain Gres Tiles for preventing growth of fungi (molds) and algae on surfaces.

With the increasing demand of biomaterials, numerous studies have been developed seeking to improve its properties through new obtaining and manufacturing processes. This work aimed to aggregate antimicrobial property to a biocomposite constituted of a matrix of ultra-high molecular weight polyethylene (UHMWPEE) and hydroxyapatite, by the incorporation of zinc oxide nanoparticles. The samples were prepared based on a standard composition containing 95.0 wt% of UHMWPEE and 5.0 wt% of hydroxyapatite (blank). Three compositions were evaluated ranging the amount of zinc oxide nanoparticles incorporated in the standard sample. It was observed that the increase of zinc oxide concentration aggregate a good antibacterial property in the samples tested without cause significant changes in the mechanical properties of the composites.

Summary: Purpose: Several lines of evidence indicate that there exists a relation between ovarian hormones and epilepsy. Estrogens decrease seizure threshold and increase brain excitability, whereas progesterone has an inhibitory effect and reduces epileptiform activity. Recently considerable interest has turned to neuroactive steroids, a group of progesterone metabolites, as endogenous modulators of excitability of the central nervous system (CNS). Their ability to alter neuronal firing rapidly occurs through interaction with γ-aminobutyric acid (GABA) A receptor complex. In a previous experience, serum allopregnanolone (3α-OH-5α-pregnan-20-one) levels were measured in 15 women with partial epilepsy in the intercritical phase, and no significant differences were found between patients and control subjects. Methods: To find out if there are changes in serum allopregnanolone levels after epileptic seizure, blood samples were drawn immediately, 15 min, and 6 h after a seizure in seven fertile females with partial epilepsy. Results: The most interesting finding is that allopregnanolone increases in serum during the first 15 min after partial seizures (p < 0.05) and decreases after 6 h. Conclusions: These data are consistent with a role for allopregnanolone in the control of neuronal excitability and seizures.

The effect of different levels of daily allowance and supplementation on intake, milk production and composition and per hectare productivity was studied. Pasture consisted of an association of alfalfa (Medicago sativa), tall fescue (Festuca arundinacea) and prairie grass (Bromus wildenowii) and high moisture corn was used as supplement. 32 cows were allocated to four levels of pasture allowance (NA) and two levels of energy supplementation (SE). Pasture intake and individual and per hectare production were affected by NA, but SE had no signifi cant effect. No interactions were detected between any of the variables. Milk composition were not affected by NA, whereas only non fat solids were affected by SE. Liveweight change and condition score did not show differences among treatments. Urea level in both, plasma and milk, was not affected by NA, whereas the level of urea in plasma showed a trend to be different and the level of urea in milk was signifi cantly different for SE. Critical levels of pasture allowance which directly affect the productivity per hectare, need to be reached in order to perform a signifi cant increase of individual production. Milk fat and protein concentration did not appear to be responsive variables to different levels of supplementation and allowance, whereas the little variation in urea levels, as a response to a greater level of supplementation, did not make this a valuable tool to improve the milk protein constituents. Se estudio el efecto que distintos niveles de asignacion diaria y suplementacion producen sobre el consumo, la produccion y composicion de la leche y la productividad por hectarea. La pastura utilizada fue una asociacion de alfalfa (Medicago sativa), festuca (Festuca arundinacea) y cebadilla criolla (Bromus wildenowii) y el suplemento fue grano de maiz humedo. Se utilizaron 32 vacas y se establecieron cuatro niveles de asignacion de pastura (NA) y dos niveles de suplementacion energetica (SE). El consumo de pastura y la produccion individual y por hectarea fueron afectados por NA y no por SE. Al igual que para el resto de las variables, no se detectaron interacciones entre NA y SE. La composicion de la leche no fue afectada por NA, mientras que SE solo tuvo efecto sobre los solidos no grasos. La evolucion del peso vivo y del estado corporal no mostraron diferencias entre tratamientos. Los niveles de urea en plasma y leche no difi rieron signifi cativamente para NA, no ocurriendo lo mismo para SE, donde el nivel de urea en plasma tendio a diferir y el nivel de urea en leche difi rio signifi cativamente. Se concluyo que para conseguir aumentos signifi cativos en la produccion individual es necesario ofrecer niveles de asignacion que afectan negativamente la produccion por hectarea. La concentracion de grasa y proteina de la leche no parecieron ser variables sensibles a distintos niveles de suplementacion y asignacion, mientras que la escasa variacion en los niveles de urea, debida al mayor nivel de suplementacion, relativizo el valor de esta herramienta para mejorar la composicion de la proteina lactea.

The goal was to evaluate acoustic analysis as a means to monitor and quantify chewing behaviour, and to estimate DM intake of forages with a wide range of water and fibre content. Each of three Angus steers (284–316 kg of body weight) was fed 32 treatments resulting from the factorial combination of four amounts ( i.e. 75, 150, 225 and 300 g dry matter, DM), two particle lengths ( i.e. chopped or whole), two water contents ( i.e. fresh or hay), and two species ( i.e. grass or alfalfa). Behaviour was videotaped and chewing sound was recorded using a microphone attached to the steers foreheads. Intake rate of DM was higher for alfalfa versus grass higher (33.0 ± 2.03 versus 28.7 ± 2.04 g DM/min), and lower in fresh forages versus hays (28.0 ± 2.04 versus 33.7 ± 2.04 g DM/min). Fresh forage was chewed more than hay (3.1 ± 0.19 versus 2.4 ± 0.19 chews/g DM) demonstrating that chewing was primarily affected by water content of forage. Alfalfa hay was chewed less than grass hay, but fresh grass and fresh alfalfa did not differ from each other and required more chewing than fresh forages. The impact of forage internal water in chewing was clear, since chews per g of neutral detergent fibre (NDF) differed among the forages, but for fresh alfalfa (the forage with the most water and the least NDF), it was much higher than for the rest. There was little evidence of an impact of particle size on chewing behaviour, probably because all forages had very long particles. Of the variation of energy in chewing sound (E), 66% was explained by DM intake (DMI). The relationship between E and DMI was linear, and the slope was 28% higher for fresh forages versus hays (P=0.033). Volume of chewing sound explained the most variation in E/DMI, and it was higher for fresh forage versus hays, whereas chews/DMI was the component of E/DMI most affected by forage characteristics. The DMI was estimated accurately based on easily observable behavioural and acoustic variables. Number of chews, cumulative sound energy and forage moisture ( i.e. fresh versus hay) were the most important predictors. The prediction error in cross-validation was 27.3 g DM (coefficient of variation = 16%, R 2 = 0.89). Acoustic analysis yields more useful information than simple the number and rate of chewing, and should be further developed as method to research and monitor chewing behaviour of ruminants.

The 3alpha-hydroxy metabolites of progesterone (P), 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone, A-PREG) and 3alpha-hydroxy-5beta-pregnan-20-one (pregnanolone, PREG), have been found to be among the most potent ligands of gamma-aminobutyric (GABA)-A receptors; in experimental animals, they have been found to have anxiolytic, hypnotic and anticonvulsant effects. Similar to those of the benzodiazepines and barbiturates that interact with GABA-A receptors. The present study was undertaken to determine plasma A-PREG and PREG concentrations in the luteal phase in women with partial epilepsy, in order to determine if an impaired metabolism of P occurs in this convulsive disorder. We measured plasma P, A-PREG and PREG levels in 15 women with partial epilepsy in the intercritical phase, and in 15 age-matched healthy women, during the luteal phase of the ovarian cycle (22nd-24th day). The mean plasma +/- S.E. A-PREG levels (three blood samples) were 0.7 +/- 0.6 ng/ml in the epileptic women and 0.5 +/- 0.2 ng/ml in controls, with no significant difference between the two groups (p = NS); the PREG levels were also similar (1.4 +/- 1 ng/ml and 1 +/- 1.1 ng/ml, respectively: p = NS). A significant correlation was found between P levels and both A-PREG and PREG levels (r = 0.72, p0.001 and r = 0.79, p0.001, respectively). There were no significant differences between the two groups in terms of serum adrenocorticotropic hormone, cortisol, dihydroepiandrosterone-sulfate, follicle stimulating hormone, prolactin, luteinizing hormone or estradiol levels.

This study was undertaken to determine plasma allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one, A-PREG) and pregnanolone (3alpha-hydroxy-5beta-pregnan-20-one, PREG) concentrations in the luteal phase (22nd to 24th day of the ovarian cycle) in 15 women with partial epilepsy and catamenial exacerbation of the seizures in the intercritical phase and in 15 healthy women matched for age in order to determine if an impaired metabolism of 3alpha-hydroxymetabolites of progesterone (P) occurs in this convulsive disorder. No significant differences between the two groups were found with respect to the mean plasmatic A-PREG and PREG levels. A significant correlation was found instead between P and A-PREG or PREG concentrations.

Solid-State Polymerisation of a ‘Push-Pull’-Diacetylene Solid-state polymerisation of ‘push-pull’-diacetylene 5-(diphenylamino)-1-phenylpenta-2,4-diyn-1-one (1d), initiated by heating of crystals of 1d at 90°, gives ‘push-pull’ poly-diacetylene 2d. X-Ray results and spectroscopic data of monomer 1d as well as of polymer 2d are discussed.

The thermodynamic properties and treatments of alkali-metal amalgams, in connection with emf measurements of amalgam concentration cells, are discussed in terms of different choice of standard state.

When amorphous PET filaments are treated in acetone-water mixtures under controlled conditions, they retain amorphous properties. The T g 's and T c 's are lowered well below the usual values and at the same time the structure becomes swollen. Ageing the treated polymer freed from acetone results in a reversible process that gives transition values close to the values for the untreated sample; but the polymeric phase remains swollen. A combined action of primary and secondary plasticizers is proposed in this paper.

Synthesis, 13C-NMR Spectra, and X-Ray Investigation of ‘Push-Pull’ Diacetylenes Phenyl-substituted ‘push-pull’ diacetylenes 1f and 1g have been prepared by acetylation and benzoylation of the appropriate lithiodiynylamines 4 (Scheme 2). 13C-NMR spectra of diacetylenes 1a–g (Table 1) are discussed with respect to the expected polarisation of the diacetylene unit by ‘push’ and ‘pull’ substituents. X-Ray investigations of 1c, 1e, and 1f have been performed in view of the planned solid-state polymerisation of ‘push-pull’ diacetylenes. In the crystalline state, diacetylenes 1c and 1f are stacked, however, the stacking parameters do not allow a solid-state polymerisation.

Synthesis of Triafulvene-Precursors from Trisubstituted Cyclopropanes Trisubstituted cyclopropanes 5a–f are prepared by carbene addition to the appropriate olefins. While 5a (Y = OAc) and 5c (Y = Cl) rearrange in the presence of BuLi, 5d (Y = SPh) is stable enough to allow the envisaged sequence for triafulvene (Scheme 2) : halogen-Li exchange, followed by methylation of 6d, gives 7d in a 93% yield; after base-induced elimination of HBr from 7d, the key precursor 1-methylene-2-(phenylthio)cyclopropane (9, 70% yield) is isolated. Compound 9 is transformed into the corresponding sulfoxide 10 (83%), sulfone 11 (80%), and sulfonium fluoroborate 12 (95% yield) by subsequent oxidation and methylation, respectively. Some 1H-NMR results of cyclopropanes 5a–f and 7d as well as of methylidene-cyclopropanes 9–11 are discussed.

Synthesis of ‘Push-Pull’ Diacetylenes The first synthesis of push-pull diacetylenes of type 1 is described. Reaction of perchlorobutenyne (8) with two equivalents of dialkylamine, followed by dechlorination using two equivalents of butyllithium gives lithio-dialkylamino-diynes 7. Final acylation of these intermediates leads to push-pull diacetylenes 1b–1e in good yields. The method allows the introduction of both push and pull substituents in a simple one-pot-procedure. In addition, 1a is prepared by hydroxymethylation of lithio-morpholino-diyne 7c, followed by oxidation with manganese dioxide in acetone.

(1974). REDUCTIVE ALKYLATION OF ACRYLONITRILES AND ACRYLATES. Organic Preparations and Procedures International: Vol. 6, No. 6, pp. 299-303.

Effects of macromolecular orientation on the crystallization of preoriented poly(ethylene terephthalate) filaments were studied. Infrared spectrophotometry and differential scanning calorimetry analyses showed that macromolecular segments in the trans conformation begin to crystallize below the glass transition temperature. Since filaments prepared by stretching at room temperature have different degrees of orientation, it is possible to evidence correlations between crystallization from an anisotropic matrix and the resulting morphology.

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of antibodies to influenza A/Hong Kong/1/68, influenza A/Victoria/3/75, influenza B/Hong Kong/5/72, and parainfluenza type 1 viruses. Development and standardization of the method indicated that an acetone-ethyl alcohol mixture was a suitable fixative for the preparation of the solid-phase coupled antigen. The addition of sodium azide to the enzyme-conjugated solution and the concentrations of the enzyme-conjugate antiglobulin and test sera employed were all critical factors in the success of the ELISA procedure. The ELISA test was specific; there was no cross-reaction between influenza A and B or parainfluenza type 1 viruses. The concordance between ELISA and hemagglutination inhibition results suggested that both tests probably detected the same type of antibodies. The ELISA procedure was 8 to 64 times more sensitive than complement fixation and/or hemagglutination inhibition tests. Low levels of antibody in patients' sera were detected only by the ELISA test. During the course of the testing period false positive reactions were not encountered. The results of ELISA could be obtained within 3 h. The ELISA test required a very small amount of serum and, therefore, offered an opportunity to detect the presence of maternal antibodies to influenza viruses in blood collected from infants by heel prick.

Attempted Synthesis of Calicene from Trisubstitued Cyclopropanes and Cyclopentenone The Li carbenoids 4, prepared by treatment of substituted 1,1-dihalocyclopropanes with BuLi, are reacted with cyclopent-2-enone under thermodynamic and kinetic control (Scheme 1). In general, the latter procedure gives better yields of cyclopropylcyclopentenols 5a–e, but the reaction seems to be controlled mainly by the steric and electronic properties of the substituent Y. So, with 4b and 4e, the main reaction is the attack of the carbenoid at C(1) of cyclopent-2-enone, while 4a (Y = PhS) predominantly deprotonates the ketone (Scheme 4). Whereas 5d and 5e can easily be converted to the dihydrocalicenes 6d and 6e (Scheme 6), the attempted elimination of H2O from 5a–c leads to the rearranged products 13–2 due to the opening of the cyclopropane ring (Scheme 5). Finally, the generation of the parent compound 2 from the silylated precursor 6d is attempted: treatment with MeO− gives the addition products 18A/18B, while the reaction with Br2 provides 19 by a bromination/dehydrobromination sequence (Scheme 7).

Isotropic poly(ethylene terephthalate) films, when thermally treated above 180°C, showed an inversion in dyeing behaviour as well as in light fastness. Similar results were found with anisotropic samples thermally treated above 150°C. The morphological characterization of the films showed the inversion points to occur always at a crystallinity index of about 0.5, but with larger crystallite dimensions in the anisotropic samples. The phenomenon is interpreted assuming that dye diffusion can be explained by replacing the usual “free volume” model by the “pore” model. Isotrope Polyethylenterephthalat-Filme zeigten nach Temperung oberhalb 180°C eine Umkehr des Farbeverhaltens und der Lichtechtheit. Ahnliche Ergebnisse wurden mit anisotropen Filmen bei thermischer Behandlung oberhalb 150°C erhalten. Die morphologische Untersuchung der Filme zeigte, das die Umkehr immer bei einem Kristallinitats-index von etwa 0,5 auftritt, wobei in den anisotropen Proben jedoch grosere Kristallite vorliegen. Die Erscheinung wird mit der Annahme interpretiert, das die Farbstoffdiffusion durch den Wechsel vom ublichen Freien-Volumen-Modell zu einem Poren-Modell bestimmt wird.

Solutions of tetraheptylammonium bromide, iodide, nitrate, or perchlorate in ethyl bromide behave as anionic liquid membranes with ideality degrees close to 100%. In the cases of tetra­ heptylammonium fluoride, or chloride, the ideality degrees are about 80%. A picture of the charac­teristics and structures of this class of membranes is given

New syntheses of polyfunctional long-chain compounds were performed by alternating free radical additions of 5-(methoxycarbonyl)-pentyl radical to pails of conjugated olefins. Copolymerization was avoided by a metal salt redox system, which selectively oxidizes the radicals involved. Quantitative data of relative reactivities towards α-methylstyrene, acrylic acid, methyl acrylate, acrylonitrile and maleic anhydride emphasize the nucleophilic character of the 5-(methoxycarbonyl)-pentyl radical. Theoretical and synthetic aspects are discussed.

Summary The formation of PbEt4 by reduction of EtBr at Pb cathodes in propylenecarbonate (PC) solutions with tetraalkylammonium salts as supporting electrolyte has been studied. EtBr-PC interactions, static potentials of Pb, steady state potentiostatic polarization curves, material yields and current efficiency of the main and side reactions as functions of the electrode potential, have been examined. On the basis of these results, a reaction mechanism has been proposed.

Due to the simultaneously unknown individual ion activity coefficients and liquid-junction potentials, a reasonable convention must be introduced defining the former in order to permit the calculation of the latter. The Guggenheim convention is analysed and chosen. Examples are reported of determination of potentials arising at junctions between concentrated strong acids and salt bridges. Liquid junction potentials set up between two concentrated strong acids at identical molalities are also considered, on the basis of a modified Henderson equation.

Differential thermal analysis (DTA) curves for the polymerization of triallyl cyanurate show two exothermic maxima. By integrating the area under the DTA curves the heats evolved during each exotherm are determined. Combination of these heat values with infrared spectral data indicates that the first step in the polymerization of TAC involves polymerization of two allyl groups, and the second step involves rearrangement to the polymerized triallyl isocyanurate form followed by polymerization of the remaining allyl group. Heats of combustion of TAC and TAIC indicate that the magnitude of the heat released during the second exotherm is reasonable and in line with the proposed mechanism.

A new method of homolytic alkylation of heteroaromatic bases is described, in which the silver-catalysed oxidative decarboxylation of acids by peroxydisulphate is used as a source of alkyl radicals. The method is particularly noteworthy because of the good yields and the high selectivity obtained, due to the nucleophilic character of the alkyl radicals; for synthetic interest it is comparable to electrophilic alkylation in the homocyclic series.

The direct introduction of α-oxyalkyl groups into heteroaromatic bases has been achieved by means of various oxidising agents: hydrogen peroxide, t-butyl-hydroperoxide, ammonium peroxy-disulphate, sodium perborate and bis-(4-t-butylcyclohexyl)-peroxydicarbonate. The good yields and the complete selectivity obtained are due to the nucleophilic character of the α-oxyalkyl radicals. A quantitative study concerning the nucleophilic character of the dioxanyl radical, carried out by measuring the relative rates of attack on 4-substituted quinolines; revealed in detail all the features of nucleophilic substitutions.

Differential thermal analysis data and infrared spectra are utilized to establish the mechanism by which a particular triallyl cyanurate-polyester (Vibrin 135) resin polymerizes. It is shown that approximately one-fourth of the polyester double bonds are of the furnarate type and that only these are capable of homopolymerization. In Vibrin 135, however, all of the polyester double bonds polymerize, along with two of the triallyl cyanurate double bonds, giving rise to one exothermic peak. From the nature of this polymerization it is inferred that a substantial amount of copolymerization occurs. Polymerization of the final triallyl cyanurate double bond, along with isomerization to the polymerized triallyl isocyanurate form, gives rise to a second exothermic peak. Correlation of measured heats of polymerization and infrared data tends to substantiate the proposed mechanism.

Homolytic alkylation of pyridine, quinoline and acridine by redox systems is a selective process as regards orientation and reactivity. The synthetic aspects and the mechanism of the reduction of oxaziranes and homolytic substitution are discussed.

The determination of transference numbers for different doped as well as undoped sodium-β-aluminas has been carried out by means of a method based on emf measurements of amalgam concentration cells of the type Nax2Hg1−x2/sodium-β-alumina/Nax1Hg1−x1 at 25°C. The details of this method, whose validity extends also to cationic conducting solids other than β-aluminas, are described and discussed for comparison with the results of previous investigations.