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1‐O‐Acylceramides (1‐OACs) have a fatty acid esterified to the 1‐hydroxyl of the sphingosine head group of the ceramide, and recently we identified these lipids as natural components of human and mouse epidermis. Here we show epidermal 1‐OACs arise shortly before birth during the establishment of the water permeability barrier in mice. Fractionation of human epidermis indicates 1‐OACs concentrate in the stratum corneum. During in vitro maturation into reconstructed human epidermis, human keratinocytes dramatically increase 1‐OAC levels indicating they are one source of epidermal 1‐OACs. In search of potential enzymes responsible for 1‐OAC synthesis in vivo, we analyzed mutant mice with deficiencies of ceramide synthases (Cers2, Cers3, or Cers4), diacylglycerol acyltransferases (Dgat1 or Dgat2), elongase of very long fatty acids 3 (Elovl3), lecithin cholesterol acyltransferase (Lcat), stearoyl‐CoA desaturase 1 (Scd1), or acidic ceramidase (Asah1). Overall levels of 1‐OACs did not decrease in any mouse model. In Cers3 and Dgat2‐deficient epidermis they even increased in correlation with deficient skin barrier function. Dagt2 deficiency reshapes 1‐OAC synthesis with an increase in 1‐OACs with N‐linked non‐hydroxylated fatty acids and a 60% decrease compared to control in levels of 1‐OACs with N‐linked hydroxylated palmitate. As none of the single enzyme deficiencies we examined resulted in a lack of 1‐OACs, we conclude that either there is functional redundancy in forming 1‐OAC and more than one enzyme is involved, and/or an unknown acyltransferase of the epidermis performs the final step of 1‐OAC synthesis, the implications of which are discussed. [ABSTRACT FROM AUTHOR]

Contaminant concentrations from the Sacramento-San Joaquin River watershed were determined in water samples mainly during flood flows in an ongoing effort to describe contaminant loads entering San Francisco Bay, CA, USA, Calculated PCB and total mercury loads during the 6-year observation period ranged between 3,9 and 19 kg/yr and 61 and 410 kg/yr, respectively. Long-term average PCB loads were estimated at 7.7 kg/yr and total mercury loads were estimated at 200 kg/yr. Also monitored were PAHs, PBDEs (two years of data), and dioxins/furans (one year of data) with average loads of 392, 11, and 0.15/ 0.014 (OCDD/OCDF) kg/yr, respectively. Organochlorine pesticide loads were estimated at 9.9 kg/yr (DDT), 1.6 kg/yr (chlordane), and 2.2 kg/yr (dieldrin). Selenium loads were estimated at 16 300 kg/yr. With the exception of selenium, all average contaminant loads described in the present study were close to or below regulatory load allocations established for North San Francisco Bay. [ABSTRACT FROM AUTHOR]

We report on the magnetic iron boron nitride (BN) nanoceramic fabricated by a hot-pressing (HP) method. Structural, magnetic and ac electrical conductivity studies have been performed. It was found that the material has core-shell structure where BN layers coat Fe cores. The iron cores consist of the mixture of crystalline and amorphous phases or are single crystalline. The magnetization measurements showed the expected high values of magnetic saturation and neither BN coating, nor increased strain affect the magnetic properties of this material, whereas other physical properties such as resistivity or hardness are significantly improved. The high magnetic saturation of the Fe:BN nanoceramic combined with relatively high resistivity makes this material very promising for radiofrequency application. [ABSTRACT FROM AUTHOR]

In this work, we have examined modifications of structural and optical properties of Y3Al5O15:Ce3+ (Ce3+:YAG) material when transforming from nanograins to nanoceramic form under high pressure. Initial YAG material with 0.5% of Ce3+ was prepared using modified Pechini and transformed to nanoceramic at low temperature with a working pressure of 4 GPa. Structural properties of both samples (nanopowder and nanoceramic) have been examined with X-ray diffraction and scanning electron microscope. Optical properties have been examined using photoluminescence (PL) spectroscopy, PL-excitation spectroscopy at different temperatures, and time-resolved spectroscopy. Based on results obtained, excitation mechanism of Ce3+ ions has been explained. The main 560 nm emission band along with a new 400 nm emission band allowed to cover the whole visible spectral range. Moreover, it has been found that under high-pressure treatment the amorphous shell of YAG core appears, leading to increased 5d electrons-lattice interaction. This, in turn, reduces PL decay time and increases emission intensity of nanoceramic sample. [ABSTRACT FROM AUTHOR]

In this work, we have examined modifications of structural and optical properties of Y3Al5O15:Ce3+ (Ce3+:YAG) material when transforming from nanograins to nanoceramic form under high pressure. Initial YAG material with 0.5% of Ce3+ was prepared using modified Pechini and transformed to nanoceramic at low temperature with a working pressure of 4 GPa. Structural properties of both samples (nanopowder and nanoceramic) have been examined with X-ray diffraction and scanning electron microscope. Optical properties have been examined using photoluminescence (PL) spectroscopy, PL-excitation spectroscopy at different temperatures, and time-resolved spectroscopy. Based on results obtained, excitation mechanism of Ce3+ ions has been explained. The main 560 nm emission band along with a new 400 nm emission band allowed to cover the whole visible spectral range. Moreover, it has been found that under high-pressure treatment the amorphous shell of YAG core appears, leading to increased 5d electrons-lattice interaction. This, in turn, reduces PL decay time and increases emission intensity of nanoceramic sample. [ABSTRACT FROM AUTHOR]

Lu2-xHoxO3 (x = 0.015-0.211) nanocrystals were synthesized by the modified Pechini method, and their nanoceramics were produced by the high-pressure low-temperature technique. Structural, morphological studies, and distribution particle size of nanocrystals and sintered pellets were carried out using X-ray powder diffraction, Raman spectroscopy, electron microscopy, and electron diffraction. The optical spectroscopy studies of Ho3+ were carried out using optical absorption and emission, as well as lifetime measurements. [ABSTRACT FROM AUTHOR]

An α1a-adrenoceptor-selective antagonist has the potential to be a new benign prostatic hyperplasia drug with reduced side-effects. Modification of the non-selective antagonist BE2254 led to the development of a series of tetralin analogs. Evaluation of these compounds in cloned human α1-adrenoceptors resulted in the discovery of an analog that showed selectivity toward the human α1a-adrenergic receptor subtype. The compound also showed moderate potency to block human prostate muscle contraction. [ABSTRACT FROM AUTHOR]

Hackmanite Na8Al6Si6O24(Cl,S)2 samples are prepared by solid state reaction of stoichiometric mixtures of zeolite A, NaCl, and Na2SO4 (850 °C, 2 h, 12% H2/N2). [ABSTRACT FROM AUTHOR]