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Inactivating SPRED1 mutations cause Legius syndrome, an autosomal dominant RASopathydescribed in 20071. Like Neurofibromatosis Type 1 (NF1), features include cafe-au-lait macules and skin fold freckling. Although neurofibromas, optic gliomas, Lisch nodules, tibial pseudarthrosis and nerve sheath tumors are not seen in Legius syndrome, other symptoms and signs common to the RASopathies such as Noonan-like facial features, pulmonary stenosis, pectus deformity and learning disabilities are reported2,3. This article is protected by copyright. All rights reserved.

This study attempted to clarify the difference in eggshell pigmentation between blue-shelled ducks (BSD) and white-shelled ducks (WSD). The eggshell pigmentation deposition process is discussed. Ultraviolet spectro-photometer and HPLC were used to determine the biliverdin concentration in the shell gland, uterus liquid and eggshell at 6, 12, 18, 20, 23.5 h post-oviposition. The biliverdin concentration in the eggshell and uterus fluid showed significant differences between BSD and WSD, but not in the shell gland. The heme oxygenase activity in the shell gland of both kinds of ducks remained mostly constant during the ovulatory cycle with no variation. The assay of exogenous biliverdin injection into the shell gland antrum in the WSD indicated that exogenous biliverdin could be deposited continuously into the eggshell until the source was exhausted. A layer-by-layer dissolution assay was used to examine the eggshell pigment deposition process. The biliverdin concentration in the first to sixth layers of the eggshell in the BSD was significantly higher than that in the white-shelled counterpart. The blue pigment concentration increased persistently from the 6 th layer to the 1 st layer. The BSD eggshells did not accumulate a large quantity of biliverdin in the most external layer. They tended to increase the deposition layer by layer. Our results demonstrated that different BSD and WSD eggshell colors were influenced by the amount of biliverdin in the uterus fluid and not determined by the amount of biliverdin in the shell gland. This implies the existence of a mechanism that controls biliverdin transportation from the shell gland into the uterus fluid, thereby playing a key role in regulating duck eggshell color.

The response of alanine solid state dosimeters to ionizing radiation strongly depends on particle type and energy. Due to nuclear interactions, neutron fields usually also consist of secondary particles such as photons and protons of diverse energies. Various experiments have been carried out in three different neutron beams to explore the alanine dose response behavior and to validate model predictions. Additionally, application in medical neutron fields for boron neutron capture therapy is discussed.Alanine detectors have been irradiated in the thermal neutron field of the research reactor TRIGA Mainz, Germany, in five experimental conditions, generating different secondary particle spectra. Further irradiations have been made in the epithermal neutron beams at the research reactors FiR 1 in Helsinki, Finland, and Tsing Hua open pool reactor in HsinChu, Taiwan ROC. Readout has been performed with electron spin resonance spectrometry with reference to an absorbed dose standard in a (60)Co gamma ray beam. Absorbed doses and dose components have been calculated using the Monte Carlo codes fluka and mcnp. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using the HansenOlsen alanine response model.The measured dose response of the alanine detector in the different experiments has been evaluated and compared to model predictions. Therefore, a relative effectiveness has been calculated for each dose component, accounting for its dependence on particle type and energy. Agreement within 5% between model and measurement has been achieved for most irradiated detectors. Significant differences have been observed in response behavior between thermal and epithermal neutron fields, especially regarding dose composition and depth dose curves. The calculated dose components could be verified with the experimental results in the different primary and secondary particle fields.The alanine detector can be used without difficulty in neutron fields. The response has been understood with the model used which includes the relative effectiveness. Results and the corresponding discussion lead to the conclusion that application in neutron fields for medical purpose is limited by its sensitivity but that it is a useful tool as supplement to other detectors and verification of neutron source descriptions.

Experimentally, two-stage oxidation of spent low-level radioactive resin was found by thermo-gravimetric analysis (TGA). About 24% of the spent resins was oxidized at 600 to 900 K. Online Fourier t...

Speciation of copper in the micropores of zeolites and a contaminatedsoil was studied by extended X-ray absorption fine structural (EXAFS) spectroscopy. The Fourier transformed EXAFS data showed that copper oxide in zeolites ZSM-5 and ZSM-48 possessed a Cu-O bond distance of 1.95 A with coordination numbers (CNs) of 1–2. Since ZSM-5 and ZSM-48 possessed channel openings of 5–6 A, the possible sizes of the linear-type copper oxides in these confined pores were 2.93–2.95 A. However, in the supercages (∼13 A) and channels (7.4 A) of zeolite Y, a three dimensional structure of CuO was observed. Interestingly, we found that CuO in the Cu-contaminated soil had a similar structure to that in ZSM-5 or ZSM-48. Nevertheless, the EXAFS data indicated that the CNs of Cu-O and Cu-O-Cu were 0.4 and 0.3, respectively, suggesting a highly perturbed copper oxide in the irregular micropores of the contaminated soil.

In Taiwan, over 800 thousand tons per year (TPY) of biowastes such as sugar cane bagasse, sugar cane leaf, rice straw, and corn leaf are produced. These biomasses are the major wastes of farms and are abundantly available. However, these biowastes cause disposal and landfill problems. The main component of these biowaste ashes is SiO 2 . High crystallinity (99% + ) zeolites ZSM-5 and ZSM-48 synthesized from the reaction mixtures containing an amorphous silica source from ashes of these biowastes' gasification were investigated. The Sι/Al ratios of synthetic zeolite products were determined by atomic adsorption, X-ray fluorescence (XRF), and induced couple plasma/mass spectroscopies (ICP/MS). X-ray powder diffraction (XRD) and scanning electron microscopy/energy dispersive spectroscopy (SEWEDX) data indicate ZSM-5 or ZSM-48 with a high crystallinity can be obtained at a 48 h crystallization time in a high pressure (15 atm) autoclave at 433 K.

Experimentally incorporated Zr or Ti into the framework of MCM-41 could enhance the photocatalytic decomposition of H 2 O to H 2 . The hydrogen yield, for instance, on Zr-MCM-41 was about 7 mmol H 2 /hr-gZrO 2 . The enhancement of Zr-MCM-41 was over 80 times if compared to the bulk ZrO 2 . The Ti-MCM-41 also possessed an enhancement of about 17 times for the H 2 vield (over TiO 2 ).

The mechanism responsible for the electroless copper deposition on a copper electrode in an acidic copper sulfate solution upon laser irradiation was investigated. The system served as a thermogalvanic cell and a highly selective copper deposit was formed at the laser‐irradiated center without any chemical reductant added. The deposit's thickness reached 510 μm after an hour's irradiation with the incident laser power density being controlled at . The deposition rates, however, decayed as the incident laser power was further raised. Finally an etched hole instead of a deposit was found as the incident laser power density exceeded . The rather peculiar decay of the copper deposition rate at high incident laser power densities can be interpreted to be owing to three competitive processes involved in the electroless copper deposition: (i) a thermogalvanic deposition process, which is the predominant one at the lower incident laser power densities condition, (ii) a copper dissolution process due to the corrosion reaction, , which is predominant at high incident laser power densities, (iii) incomplete consecutive discharge reduction process due to the loss of cuprous ions by violent microstirring under high laser power density irradiation condition. A net etching effect instead of an electroless deposition can be obtained under the extreme case.

The mechanism responsible for the electroless copper deposition on a copper electrode in an acidic copper sulfate solution upon laser irradiation was investigated. The system served as a thermogalvanic cell and a highly selective copper deposit was formed at the laser‐irradiated center without any chemical reductant added. The deposit's thickness reached 510 μm after an hour's irradiation with the incident laser power density being controlled at . The deposition rates, however, decayed as the incident laser power was further raised. Finally an etched hole instead of a deposit was found as the incident laser power density exceeded . The rather peculiar decay of the copper deposition rate at high incident laser power densities can be interpreted to be owing to three competitive processes involved in the electroless copper deposition: (i) a thermogalvanic deposition process, which is the predominant one at the lower incident laser power densities condition, (ii) a copper dissolution process due to the corrosion reaction, , which is predominant at high incident laser power densities, (iii) incomplete consecutive discharge reduction process due to the loss of cuprous ions by violent microstirring under high laser power density irradiation condition. A net etching effect instead of an electroless deposition can be obtained under the extreme case.

The purpose of this study is to investigate the influence of the ultrasound peak pressure and sonication duration on blood-brain barrier (BBB) disruption, and also seek for the optimized sonication parameter to introduce BBB-opening with minimal hemorrhagic damage. Twelve SD rats were sonicated. During sonication, the 309 kHz focused ultrasound was employed to deliver burst-mode low-pressure ultrasound to animal brains in the presence of microbubbles to introduce local and temporal BBB disruption. Different ultrasonic peak pressures and sonication durations were tested, and the BBB-disruption and accompanied hemorrhage were confirmed by brain section and histological examinations. Our results showed that the peak pressure is the major factor to generate BBB disruption, where as the sonication duration can be utilized to moderately regulate the accompanied hemorrhagic damage. We also found that the low-pressure long-duration ultrasound exposure may be beneficiary to reduce hemorrhage than high-pressure short-duration mode.

It is possible to exploit the isolation of the O-H stretching vibration in H$\_{2}$O and HOD to control the photodissociation and reaction dynamics in water molecules excited in the region of the third overtone (4$\nu \_{\text{OH}}$) of the O-H stretch. In vibrationally mediated photodissociation of H$\_{2}$O, the selection of different initial stretching states having roughly the same energy leads to drastically different populations of the vibrational states of the OH photolysis product. By exciting the O-H stretching overtone in HOD, we can selectively photolyze that bond. In bimolecular reaction experiments, we react H$\_{2}$O (4$\nu \_{\text{OH}}$) with H atoms to produce H$\_{2}$ and OH. The reaction, which is endothermic, proceeds at an undetectable rate in our room temperature measurements. Vibrationally excited water, however, reacts at roughly the gas kinetic collision rate. Applying this technique to HOD (4$\nu _{\text{OH}}$) allows us to demonstrate bond selected bimolecular chemistry in which the reaction produces only OD. This observation suggests a general approach to assessing bond controlled reactions in a variety of systems.

The pH of copper sulfate solution affects the formation of the passive layer, mainly Cu 2 O, on the copper surface under laser irradiation. The electrode process can be changed from electroless deposition to etching due to the formation of this passive material coupled with the dissolution of copper. The etching effect is obtained even under a low laser power density when the pH of the copper sulfate solution is controlled between 4.3 and 2.0

The aim of the present study was to examine the relationship between the lateral tegmental field (FTL), a cardioinhibitory area, with other cardioinhibitory areas, i.e., the ambiguus nucleus (NA) and the dorsal motor nucleus of vagus (DMV) and the caudal ventrolateral medulla (CVLM), a vasopressor inhibitory area. In 55 cats anesthetized with chloralose (40 mg/kg) and urethane (400 mg/kg), the cardiovascular responses of heart rate (HR), systemic arterial blood pressure (SAP) and vertebral nerve activity (VNA) were recorded. The FTL, NA, DMV and CVLM were identified first by stimulation (rectangular pulses in 80 Hz, 0.5 ms, 50-100 microA) and then confirmed by microinjection of sodium glutamate (Glu, 0.25M, 70 nl). In studying the influence of NA, DMV, or CVLM lesion on the Gluinduced responses in FTL, kainic acid (KA, 24 mM, 100 nl) was microinjected into the NA, DMV or CVLM. FTL stimulation produced an average decrease of HR by 55%. After KA lesioning of the ipsilateral NA or the DMV, the decreased HR induced by FTL was significantly diminished. After subsequent lesion of the contralateral DMV or NA, the bradycardia of FTL was abolished. The reduction of resting HR was more intense after lesioning the NA than DMV and with the left side more than that of the right side. These studies suggest that the cardioinhibitory responses of FTL are mediated through both NA and DMV with predominance of the former, while the hypotensive effect of FTL is mediated through CVLM. The precise pathway responsible for the FTL-induced bradycardia and hypotension is to be determined.

This paper examines how hydrocarbons affect the non-thermal plasma treatment of NOx in lean-burn engine exhausts. We have found that the NO is mainly oxidized to NO2 by NO + HO2 --> NO2 + OH, NO + RO2 --> NO2 + RO where R is a hydrocarbon radical. The O and OH radicals produced by electron-impact dissociation are consumed mainly by reactions with the hydrocarbons rather than with NO. The hydrocarbons lower the energy cost for the oxidation of NO by converting 0 and OH to HO2; the OH radical is then reproduced when NO is oxidized by HO2. This cyclic process leads to a very efficient utilization of the plasma-produced radicals for the selective partial oxidation of NO to NO2. This result suggests that gas-phase reactions in the plasma alone cannot lead to the chemical reduction of NOx. Any reduction of NOx to N2 can only be accomplished through heterogeneous reactions of NO2 with surfaces or particulates

Non-thermal plasma processing is an emerging technology for the abatement of volatile organic compounds (VOCs) and nitrogen oxides (NO{sub x}) in atmospheric pressure gas streams. Either electrical discharge of electron beam methods can produce these plasmas. This paper presents a comparative assessment of various non-thermal plasma reactors. The goal of our project is two-fold: (1) to understand the feasibility and scalability of various non-thermal plasma reactors by focusing on the energy efficiency of the electron and chemical kinetics, and (2) to optimize process parameters and provide performance and economic data. Experimental results using a compact electron beam reactor, pulsed corona reactor and dielectric-barrier discharge will be presented. These reactors have been used to study the removal of NO{sub x} and a wide variety of VOCs. The effects of background gas decomposition and gas temperature on the decomposition chemistry have been studied. The decomposition mechanisms are discussed to illustrate how the chemistry could strongly affect the economics of the process. An analysis of the electron kinetics show that electrical discharge reactors are the most suitable only for processes requiring O radicals. For pollution control applications requiring copious amounts of electrons, ions, N atoms or OH radicals, the sue of electron beam reactors is generally the best way of minimizing the electrical power consumption.

Vibrational excitation provides a means for identifying the degrees of freedom in a molecule that are spectators or participants in a bimolecular reaction. In our study of the reactions of vibrationally excited H2O with H and Cl atoms and vibrationally excited HCN with H, O, and Cl atoms, we find that in direct reactions the nonreacting bond of a molecule is a spectator to the reaction. When the nonreacting bond participates in the reaction, the reaction mechanism is not direct but proceeds through an intermediate complex.

Distributed wall loss is proposed to enhance the stability and tunability of a W-band TE01 gyrotron backward-wave oscillator (gyro-BWO). Simulation results reveal that loss effectively suppresses the unwanted transverse modes as well as the high-order axial modes (HOAMs) without degrading the performance of a gyro-BWO that operates at the fundamental axial mode. Linear and nonlinear codes are used to calculate the interaction properties. The effects of the distributed loss on the starting currents of all of the modes of interest are discussed in depth. The interacting structure is optimized for stability. The calculated peak output power is 102kW, corresponding to an efficiency of 20%. The 3dB tuning bandwidth is 1.8GHz, centered at 94.0GHz when using 5A and 100kV electron beam.

Carbon nanotube powders were synthesized by arc discharge method and incorporated into the paste to be applied in the screen printing process. It was investigated that the field emission image uniformity was efficiently improved by laser treating carbon nanotube powders. The laser energy burned out carbon particles to reveal more carbon nanotubes and graphitized carbon nanotubes. In addition to uniformity improvement, field emission properties were also reinforced after laser treating. For instance, turn-on voltage decreased from 3.2to2.2V∕μm, while field enhancement factor increased from 2200 to 2900.

The poly-gamma-glutamyl derivatives of n10-propargyl-5,8-dideazafolic acid (PDDF) with a chain length of up to five glutamate residues were synthesized from N10-propargyl-5,8-dideazapteroic acid by the solid-phase procedure. These compounds were evaluated for their antifolate activity using folate-requiring microorganisms and intact and permeabilized L1210 cells and as inhibitors of dihydrofolate reductase and thymidylate synthase derived from L. casei. The polyglutamylated derivatives of PDDF (1) were more active than the parent compound in inhibiting the growth of L. casei, thymidylate synthesis in permeabilized L1210 cells, and L. casei thymidylate synthase. Two analogues of 5,8-dideazafolic acid (2 and 3), one with a 2-butyne and another with a cyclopropylmethyl substituent at N10, were also synthesized and evaluated for their antifolate activities using the above-mentioned test systems. They were considerably less active than PDDF or its polyglutamylated derivatives. N10-Propargyl-5,8-dideazapteroyl tri-, tetra-, and pentaglutamates were equipotent with 5-fluorodeoxyuridylate as inhibitors of thymidylate synthesis in permeabilized L1210 cells. The polyglutamyl metabolites of PDDF were shown to be the most potent antifolate inhibitors of L. casei and L1210 thymidylate synthases yet described.