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Honey was reported numerous benefit containing nutritional ingredients and phytochemical such as polyphenol, flavonoid was widely used around the world. In this study, the physicochemical characteristics on the quality of coffee flower honey has been evaluated during storage. The honey was collected from Dak Lak, Buon Me Thuot, and Kon Tum province in Vietnam and stored at room temperature (30 -32°C) for 12 month. Total sugar, reducing sugar, hydroxymethylfurfural (HMF), acid value, total polyphenol content (TPC) and total flavonoid content (TFC) were evaluated for each two month to determine the quality of sensory quality and nutritional value. After 12 month storage time, the content of total sugar, and reducing sugar gradually decreased along with the increase of HMF and acid content in the coffee flower honey samples a lead to sweetness of honey is decrease, acidity, and color increase, which is a signal indicating a decline in sensory quality and nutritional value. The content of TPC and TFC increased during the first 6 -10 months of storage and then also tended to decrease, indicating that coffee flower honey should not be stored for too long (more than 10 months) because of phytochemicals reducing. [ABSTRACT FROM AUTHOR]

Author(s): M. Garg [1]; M. Zhan [1]; T. T. Luu [1]; H. Lakhotia [1]; T. Klostermann [1]; A. Guggenmos [1]; E. Goulielmakis (corresponding author) [1] The frequency of electric currents [...]

Intense light interacting with a thin film of silicon dioxide is used to generate broadband extreme ultraviolet radiation; the spectra reveal detailed information on the energy dispersion of the conduction band of silicon dioxide, which is at present inaccessible by conventional photoemission spectroscopy. Solid-state EUV spectroscopy Laser-based generation of extreme ultraviolet (EUV) radiation in gases, leading to the generation of light with frequencies that are high-order harmonics of the fundamental laser frequency, is widely used as a spectroscopy and imaging tool. High harmonics are also generated in bulk crystals, although the underlying emission mechanisms are under debate. Here Eleftherios Goulielmakis and colleagues extend the technique to generate broadband EUV radiation in thin films of silicon dioxide. The spectra reveal detailed information on the energy dispersion of the conduction band of silicon dioxide, which is at present inaccessible by conventional photoemission spectroscopy. This work is an important step in the development of the emerging field of solid-state EUV photonics. Extreme ultraviolet (EUV) high-harmonic radiation.sup.1,2 emerging from laser-driven atoms, molecules or plasmas underlies powerful attosecond spectroscopy techniques.sup.3,4,5 and provides insight into fundamental structural and dynamic properties of matter.sup.6,7. The advancement of these spectroscopy techniques to study strong-field electron dynamics in condensed matter calls for the generation and manipulation of EUV radiation in bulk solids, but this capability has remained beyond the reach of optical sciences. Recent experiments.sup.8,9 and theoretical predictions.sup.10,11,12 paved the way to strong-field physics in solids by demonstrating the generation and optical control of deep ultraviolet radiation.sup.8 in bulk semiconductors, driven by femtosecond mid-infrared fields or the coherent up-conversion of terahertz fields to multi-octave spectra in the mid-infrared and optical frequencies.sup.9. Here we demonstrate that thin films of SiO.sub.2 exposed to intense, few-cycle to sub-cycle pulses give rise to wideband coherent EUV radiation extending in energy to about 40 electronvolts. Our study indicates the association of the emitted EUV radiation with intraband currents of multi-petahertz frequency, induced in the lowest conduction band of SiO.sub.2. To demonstrate the applicability of high-harmonic spectroscopy to solids, we exploit the EUV spectra to gain access to fine details of the energy dispersion profile of the conduction band that are as yet inaccessible by photoemission spectroscopy in wide-bandgap dielectrics. In addition, we use the EUV spectra to trace the attosecond control of the intraband electron motion induced by synthesized optical transients. Our work advances lightwave electronics.sup.5,13,14,15 in condensed matter into the realm of multi-petahertz frequencies and their attosecond control, and marks the advent of solid-state EUV photonics., Author(s): T. T. Luu [sup.1] , M. Garg [sup.1] , S. Yu. Kruchinin [sup.1] , A. Moulet [sup.1] , M. Th. Hassan [sup.1] , E. Goulielmakis [sup.1] Author Affiliations: (1) [...]

Hybrid materials, based on inorganic nanoblocks incorporated into polymer networks, are an important class of functional materials. Although the kinetic of the free-radical polymerization of neat polymers has been studied for many years, both theoretically and experimentally, studies devoted to the polymerization kinetics of nanocomposite materials are rare. In this study, photosensitive hybrids formed using poly(2-hydroxyethyl methacrylate) (pHEMA) and titanium dioxide (TiO2) nanoparticles functionalized with polymerizable ligands were considered. Their bulk UV-induced free-radical photopolymerization was investigated to evaluate the potential of pHEMA/TiO2 hybrids as a material of choice for the fabrication of micro-optical devices. The influence of the nanoparticle concentration and UV intensity on the polymerization kinetics, probed in situ by Raman spectroscopy, is discussed. A decrease in the initiation rate was observed, which was attributed to the UV absorption of TiO2 nanoparticles. This leads to a decrease in the propagation rate with an increase in nanoparticle concentration. Furthermore, a decrease in the maximum C=C conversion yield was observed when the nanoparticle concentration was increased. This was attributed to the formation of microgel regions around the nanoparticles, which prevented the polymer chains from bonding with surface ligands. Despite the lower conversion yield, we demonstrated the fabrication of one-dimension (1D) photoactive microstructures in pHEMA/TiO2 hybrids. The photochromic efficiency of the obtained structure was evaluated based on the reduction in silver (Ag) ions under UV irradiation. The results show that pHEMA/TiO2 hybrids can be considered as a prospective material for the realization of photosensitive microelements. [ABSTRACT FROM AUTHOR]

It is well known that glutathione is a ubiquitous and multifunctional compound which is important in maintaining cellular redox homeostasis. The balance between the reduced (GSH) and oxidized (GSSG) forms of this tripeptide plays a fundamental role in basic physiological and metabolic processes in plants. Recently, a remarkable amount of evidence has suggested that the role of glutathione within the plant system extends beyond the basic metabolic functions and that it may ultimately act as a modulator of plant development and morphogenesis. Therefore, it is not surprising that research has begun to focus on using the glutathione redox pair system for improving regeneration of cultured cells. One of the major themes that has emerged from in vitro studies is that GSH promotes cell proliferation, while GSSG promotes organized development. Thus, in vitro manipulation of this redox compound within the culture medium could lead to an enhancement of plant regeneration. [ABSTRACT FROM AUTHOR]

Natural killer (NK) cell responsiveness in the mouse is determined in an education process guided by inhibitory Ly49 and NKG2A receptors binding to MHC class I molecules. It has been proposed that inhibitory signalling in human NK cells involves Abl-1 (c-Abl)-mediated phosphorylation of Crk, lowering NK cell function via disruption of a signalling complex including C3G and c-Cbl, suggesting that NK cell education might involve c-Abl. Mice deficient in c-Abl expression specifically in murine NK cells displayed normal inhibitory and activating receptor repertoires. Furthermore, c-Abl-deficient NK cells fluxed Ca 2+ normally after triggering of ITAM receptors, killed YAC-1 tumour cells efficiently and showed normal, or even slightly elevated, capacity to produce IFN-γ after activating receptor stimulation. Consistent with these results, c-Abl deficiency in NK cells did not affect NK cell inhibition via the receptors Ly49G2, Ly49A and NKG2A. We conclude that signalling downstream of murine inhibitory receptors does not involve c-Abl and that c-Abl plays no major role in NK cell education in the mouse., (© 2017 The Foundation for the Scandinavian Journal of Immunology.)

We report on design, production and implementation of a highly dispersive broadband dielectric multilayer mirror covering near ultraviolet range from 290 nm to 350 nm. The described mirrors, having 92% spectrally averaged reflectance in the ultraviolet range and ∼ 85 fs of group delay difference, that allow compression to ∼ 7 fs, provide a strong foundation for generation of few-fs pulses in the near ultraviolet.

Breast cancer screening behavior and attitudes was measured among a convenience sample of 275 Vietnamese American women as part of a cancer education program evaluation. Follow-up interviews were completed with 178. Only 36% reported having adequate knowledge on this topic, and 87% indicated an interest in receiving more information. Rates of receiving a mammogram were below recommended levels.