Topics in LIGO-related physics: interferometric speed meters and tidal work

In the quest to develop viable designs for third-generation optical interferometric gravitational-wave detectors, one strategy is to monitor the relative momentum or speed of the test-mass mirrors, rather than monitoring their relative position. The most straightforward design for a speed-meter interferometer that accomplishes this is described and analyzed in Chapter 2. This design (due to Braginsky, Gorodetsky, Khalili, and Thorne) is analogous to a microwave-cavity speed meter conceived by Braginsky and Khalili. A mathematical mapping between the microwave speed meter and the optical interferometric speed meter is developed and used to show (in accord with the speed being a quantum nondemolition observable) that in principle the interferometric speed meter can beat the gravitational-wave standard quantum limit (SQL) by an arbitrarily large amount, over an arbitrarily wide range of frequencies . However, in practice, to reach or beat the SQL, this specific speed meter requires exorbitantly high input light power. The physical reason for this is explored, along with other issues such as constraints on performance due to optical dissipation.

Chapter 3 proposes a more sophisticated version of a speed meter. This new design requires only a modest input power and appears to be a fully practical candidate for third-generation LIGO. It can beat the SQL (the approximate sensitivity of second-generation LIGO interferometers) over a broad range of frequencies (~ 10 to 100 Hz in practice) by a factor h/h_SQL ~ √W^(SQL)_(circ)/W_circ. Here W_circ is the light power circulating in the interferometer arms and W_SQL ≃ 800 kW is the circulating power required to beat the SQL at 100 Hz (the LIGO-II power). If squeezed vacuum (with a power-squeeze factor e^-2R) is injected into the interferometer's output port, the SQL can be beat with a much reduced laser power: h/h_SQL ~ √W^(SQL)_(circ)/W_circe^-2R. For realistic parameters (e^-2R ≃ 10 and W_circ ≃ 800 to 2000 kW), the SQL can be beat by a factor ~ 3 to 4 from 10 to 100 Hz. [However, as the power increases in these expressions, the speed meter becomes more narrow band; additional power and re-optimization of some parameters are required to maintain the wide band.] By performing frequency-dependent homodyne detection on the output (with the aid of two kilometer-scale filter cavities), one can markedly improve the interferometer's sensitivity at frequencies above 100 Hz.

Chapters 2 and 3 are part of an ongoing effort to develop a practical variant of an interferometric speed meter and to combine the speed meter concept with other ideas to yield a promising third- generation interferometric gravitational-wave detector that entails low laser power.

Chapter 4 is a contribution to the foundations for analyzing sources of gravitational waves for LIGO. Specifically, it presents an analysis of the tidal work done on a self-gravitating body (e.g., a neutron star or black hole) in an external tidal field (e.g., that of a binary companion). The change in the mass-energy of the body as a result of the tidal work, or "tidal heating," is analyzed using the Landau-Lifshitz pseudotensor and the local asymptotic rest frame of the body. It is shown that the work done on the body is gauge invariant, while the body-tidal-field interaction energy contained within the body's local asymptotic rest frame is gauge dependent. This is analogous to Newtonian theory, where the interaction energy is shown to depend on how one localizes gravitational energy, but the work done on the body is independent of that localization. These conclusions play a role in analyses, by others, of the dynamics and stability of the inspiraling neutron-star binaries whose gravitational waves are likely to be seen and studied by LIGO.

In Vitro Surfactant and Perfluorocarbon Aerosol Deposition in a Neonatal Physical Model of the Upper Conducting Airways

Objective: Aerosol delivery holds potential to release surfactant or perfluorocarbon (PFC) to the lungs of neonates with respiratory distress syndrome with minimal airway manipulation. Nevertheless, lung deposition in neonates tends to be very low due to extremely low lung volumes, narrow airways and high respiratory rates. In the present study, the feasibility of enhancing lung deposition by intracorporeal delivery of aerosols was investigated using a physical model of neonatal conducting airways. Methods: The main characteristics of the surfactant and PFC aerosols produced by a nebulization system, including the distal air pressure and air flow rate, liquid flow rate and mass median aerodynamic diameter (MMAD), were measured at different driving pressures (4-7 bar). Then, a three-dimensional model of the upper conducting airways of a neonate was manufactured by rapid prototyping and a deposition study was conducted. Results: The nebulization system produced relatively large amounts of aerosol ranging between 0.3 +/- 0.0 ml/min for surfactant at a driving pressure of 4 bar, and 2.0 +/- 0.1 ml/min for distilled water (H(2)Od) at 6 bar, with MMADs between 2.61 +/- 0.1 mu m for PFD at 7 bar and 10.18 +/- 0.4 mu m for FC-75 at 6 bar. The deposition study showed that for surfactant and H(2)Od aerosols, the highest percentage of the aerosolized mass (similar to 65%) was collected beyond the third generation of branching in the airway model. The use of this delivery system in combination with continuous positive airway pressure set at 5 cmH(2)O only increased total airway pressure by 1.59 cmH(2)O at the highest driving pressure (7 bar). Conclusion: This aerosol generating system has the potential to deliver relatively large amounts of surfactant and PFC beyond the third generation of branching in a neonatal airway model with minimal alteration of pre-set respiratory support.

显微成像荧光屏用无机闪烁单晶薄膜的研究进展

随着第三代同步辐射源的出现，由荧光屏和CCD耦合组成的、具有亚微米级空间分辨率、快速在线成像功能的探测器在医疗、安检、工业、科研等领域将会得到广泛应用．本文主要综述了成像荧光屏用材料的概况和发展趋势，重点阐述了闪烁单晶薄膜的研究及发展情况．

Genetic improvement of the herbivorous blunt snout bream (Megalobrama amblycephala)

Selection experiments with the herbivorous blunt snout bream or Wuchang bream (Megalobrama amblycephala) were started in 1985. Mass selection for size and length/depth ratio resulted in a significant increase in growth and better shape, while inbreeding led to a significant decrease in growth. The total selection ratio from fry to mature brooders was about 0.03 per cent per generation. In the grow out stage, the average daily body weight gains of two lines of fifth generation (F5) fish were 29 per cent and 20 per cent respectively more than the control group, with an average of 5.8 per cent and 4 per cent improvements per generation, respectively. The body was 4 per cent deeper in ratio of standard length/body depth. The effects of inbreeding were examined by crossing full-sibs, the offspring of which were kept without selection. The third generation inbred fish showed 17 per cent lower growth as compared to the control group, with an average of 7.5 per cent per generation. The results demonstrate that selection is a powerful tool to improve the economic traits of the blunt snout bream, but inbreeding can rapidly lead to a reduction in performance. In 2000, the 6th generation of selected bream was certified by the Chinese Ministry of Agriculture as a good breed for aquaculture.

Localização de Terminais Móveis utilizando Correlação de Assinaturas de Rádio-Frequência.

Nesta dissertação são analisados métodos de localização baseados na rede, com destaque para os métodos de correlação de assinaturas de rádio-frequência (DCM - Database Correlation Methods). Métodos baseados na rede não requerem modificações nos terminais móveis (MS - Mobile Stations), sendo portanto capazes de estimar a localização de MS legados, i.e., sem suporte específico a posicionamento. Esta característica, associada a alta disponibilidade e precisão dos métodos DCM, torna-os candidatos viáveis para diversas aplicações baseadas em posição, e em particular para a localização de chamadas para números de emergência - polícia, defesa civil, corpo de bombeiros, etc. - originadas de telefones móveis celulares. Duas técnicas para diminuição do tempo médio para produção de uma estimativa de posição são formuladas: a filtragem determinística e a busca otimizada utilizando algoritmos genéticos. Uma modificação é realizada nas funções de avaliação utilizadas em métodos DCM, inserindo um fator representando a inacurácia intrínseca às medidas de nível de sinal realizadas pelos MS. As modificações propostas são avaliadas experimentalmente em redes de telefonia móvel celular de segunda e terceira gerações em ambientes urbanos e suburbanos, assim como em redes locais sem fio em ambiente indoor. A viabilidade da utilização de bancos de dados de correlação (CDB - Correlation Database) construídos a partir de modelagem de propagação é analisada, bem como o efeito da calibração de modelos de propagação empíricos na precisão de métodos DCM. Um dos métodos DCM propostos, utilizando um CDB calibrado, teve um desempenho superior ao de vários outros métodos DCM publicados na literatura, atingindo em área urbana a precisão exigida dos métodos baseados na rede pela regulamentação FCC (Federal Communications Commission) para o serviço E911 (Enhanced 911 ).

Factors affecting the efficiency of somatic cell nuclear transplantation in the fish embryo

Procedures to improve somatic cell nuclear transplantation in fish were evaluated. We reported effects of nonirradiated recipient eggs, inactivated recipient eggs, different combinations between recipient eggs and donor cells, duration of serum starvation, generation number, and passage number of donor cells on developmental rates of nuclear transplant (NT) embryos. Exposure to 25,000 R of gamma-rays inactivated recipient eggs. Single nucleus of cultured, synchronized somatic cell from gynogenetic bighead carp (Aristichthys nobilis) was transplanted into nonirradiated or genetically inactivated unfertilized egg of gibel carp (Carassius auratus gibelio). There was no significant difference in developmental rate between nonirradiated and inactivated recipient eggs (27.27% vs. 25.71%, respectively). Chromosome count showed that 70.59% of NT embryos contained 48 chromosomes. It showed that most NT embryos came from donor nuclei of bighead carp, which was supported by microsatellite analysis of NT embryos. But 23.53% of NT embryos contained more than 48 chromosomes. It was presumed that those superfluous chromosomes came from nonirradiated recipient eggs. Besides, 5.88% of NT embryos were chimeras. Eggs of blunt-snout bream (Megalobrama amblycephala) and gibel carp were better recipient eggs than those of loach (Misgurnus anguillicaudatus) (25% and 18.03% vs. 8.43%). Among different duration of serum starvation, developmental rate of NT embryos from somatic nuclei of three-day serum starvation was the highest, reaching 25.71% compared to 14.14% (control), 20% (five-day), and 21.95% (seven-day). Cultured donor cells of less passage facilitated reprogramming of NT embryos than those of more passage. Recloning might improve the developmental rate of NT embryos from the differentiated donor nuclei. Developmental rate of fourth generation was the highest (54.83%) and the lowest for first generation (14.14%) compared to second generation (38.96%) and third generation (53.01%). (C) 2002 Wiley-Liss, Inc.

Diagnostic experiments for transport mechanisms of suspended sediment discharged from the Yellow River in the Bohai Sea

Five diagnostic experiments with a 3D baroclinic hydrodynamic and sediment transport model ECOMSED in couple with the third generation wave model SWAN and the Grant-Madsen bottom boundary layer model driven by the monthly sediment load of the Yellow River, were conducted to separately diagnose effects of different hydrodynamic factors on transport of suspended sediment discharged from the Yellow River in the Bohai Sea. Both transport and spatio-temporal distribution of suspended sediment concentration in the Bohai Sea were numerially simulated. It could be concluded that suspended sediment discharged from the Yellow River cannot be delivered in long distance under the condition of tidal current. Almost all of sediments from the Yellow River are deposited outside the delta under the condition of wind-driven current, and only very small of them are transported faraway. On the basis of wind forcing, sediments from the Yellow River are mainly transported north-northwestward, and others which are first delivered to the Laizhou Bay are continuously moved northward. An obvious 3D structure characteristic of sediment transport is produced in the wind-driven and tide-induced residual circulation condition. Transport patterns at all layers are generally consistent with circulation structure, but there is apparent deviation between the depth-averaged sediment flux and the circulation structure. The phase of temporal variation of sediment concentration is consistent with that of the bottom shear stress, both of which are proved to have a ten-day cycle in wave and current condition.

Solution-Processible Red Iridium Dendrimers based on Oligocarbazole Host Dendrons: Synthesis, Properties, and their Applications in Organic Light-Emitting Diodes

A series of novel red-emitting iridium dendrimers functionalized with oligocarbazole host dendrons up to the third generation (red-G3) have been synthesized by a convergent method, and their photophysical, electrochemical, and electroluminescent properties have been investigated. In addition to controlling the intermolecular interactions, oligocarbazole-based dendrons could also participate in the electrochemical and charge-transporting process. As a result, highly efficient electrophosphorescent devices can be fabricated by spin-coating from chlorobenzene solution in different device configurations.

Highly efficient and recoverable dendritic organocatalyst from click chemistry for the asymmetric michael addition of ketones to nitroolefins without the use of organic solvent

A series Of pyrrolidine-triazole based dendritic catalysts have been synthesized and applied directly in the asymmetric Michael addition of ketones to nitroolefins without the use of an organic solvent. Good yields (up to 99%), and high diastereoselectivities (up to syn/anti = 45:1) and enantioselectivities (up to 95% ee) have been obtained. Furthermore. the third generation catalyst can be reused at least five times without significant loss of catalytic activity. (C) 2008 Elsevier Ltd. All rights reserved.

One-step preparation and characterization of poly(propyleneimine) dendrimer-protected silver nanoclusters

Highly stable silver nanoclusters with narrow size distribution have been prepared by heating a third-generation poly(propyleneimine) dendrimer/AgNO3 aqueous solution without the additional step of introducing other reducing agents and protect agents. UV-vis absorption, transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), and X-ray diffraction (XRD) have been used to characterize the resulting products. The as-obtained sample was in coexistence of Ag and Ag2O. It also suggested that increasing temperature resulted in both the decrease in number of small particles and the increase in size of large particles.

A novel hydrogen peroxide sensor based on horseradish peroxidase immobilized in DNA films on a gold electrode

A novel third-generation hydrogen peroxide (H2O2) biosensor was developed by immobilizing horseradish peroxidase (HRP) on a biocompatible gold electrode modified with a well-ordered, self-assembled DNA film. Cysteamine was first self-assembled on a gold electrode to provide an interface for the assembly of DNA molecules. Then DNA was chemisorbed onto the self-assembled monolayers (SAMs) of cysteamine to form a network by controlling DNA concentration. The DNA-network film obtained provided a biocompatible microenvironment for enzyme molecules, greatly amplified the coverage of HRP molecules on the electrode surface, and most importantly could act as a charge carrier which facilitated the electron transfer between HRP and the electrode. Finally, HRP was adsorbed on the DNA-network film. The process of the biosensor construction was followed by atomic force microscopy (AFM). Voltammetric and time-based amperometric techniques were employed to characterize the properties of the biosensor derived. The enzyme electrode achieved 95% of the steady-state current within 2 s and had a 0.5 mu mol l(-1) detection limit of H2O2. Furthermore, the biosensor showed high sensitivity, good reproducibility, and excellent long-term stability.

One-step synthesis and size control of dendrimer-protected gold nanoparticles: A heat-treatment-based strategy

Dendrimer-protected gold nanoparticles have been facilely obtained by heating an aqueous solution containing third generation poly(propyleneimine) dendrimers and HAuCl4 without the additional step of introducing other reducing agents. Transmission electron microscopy (TEM) and UV vis data indicate the size the nucleation and growth kinetics of gold nanoparticles thus formed which can be tuned by changing the initial molar ratio of dendrimer to gold.

The electrochemical study of oxidation-reduction properties of horseradish peroxidase

Oxidation-reduction properties of horseradish peroxidase (HRP) have been investigated by using direct electrochemical methods. Two successive separated distinct one-electron processes of HRP were obtained and the related physiological processes were described. The monolayer coverage of HRP at the electrode surface is about 50 pmol/cm(2). UV-Vis spectrophotometry and stable amperometry prove that the enzyme electrode possesses catalytic activity for H2O2 in the absence of a mediator and it might offer an opportunity to build the third generation of biosensors for analytes, such as H2O2, glucose and cholesterol etc. (C) 1997 Elsevier Science S.A.

Self-assembled monolayers of thiols on gold electrodes for bioelectrochemistry and biosensors

Monolayers of biological compounds including redox proteins and enzymes, and phospholipids have been immobilized on a gold electrode surface through self-assembling. These proteins and enzymes, such as cytochrome c, cytochrome c oxidase and horseradish peroxidase (HRP), immobilized covalently to the self-assembled monolayers (SAMs) of 3-mercaptopropionic acid on a gold electrode, communicate directly electrons with the electrode surface without mediators and keep their physiological activities. The electron transfer of HRP with the gold electrode can also be mediated by the alkanethiol SAMs with electroactive group viologens on the gold electrode surface. All these direct electrochemistries of proteins and enzymes might offer an opportunity to build a third generation of biosensors without mediators for analytes, such as H2O2, glucose and cholesterol. Monensin and valinomycin have been incorporated into the bilayers on the gold electrode consisting of the SAMs of alkanethiol and a lipid monolayer, which have high selectivity for monovalent ions, and the resulting Na+ or K+ sensor has a wide linear range and high stability. These self-assembly systems provide a good mimetic model for studying the physiological function of a membrane and its associated enzyme. (C) 1997 Elsevier Science S.A.

Direct electron transfer to cytochrome c oxidase in self-assembled monolayers on gold electrodes

The monolayer of cytochrome c oxidase maintaining physiological activity and attached covalently to the self-assembled monolayers of 3-mercaptopropionic acid (MPA) on a gold electrode was obtained. The results of cyclic voltammetry show that direct electron transfer between cytochrome c oxidase and the electrode surface is a fast and diffusionless process. MPA has a dual role as both electrode modifier and the bridging molecule which: keeps cytochrome c oxidase at an appropriate orientation without denaturation and enables direct electron transfer between the protein and the modified electrode. Immobilized cytochrome c oxidase exhibits biphasic phenomena between the concentration of the electrolyte and the normal potentials; meanwhile its electrochemical behavior is also influenced by the buffer components. The quasi-reversible electron transfer process of cytochrome c oxidase with formal potential 385 mV vs. SHE in 5mM phosphate buffer solution (pH 6.4) corresponds to the redox reaction of cyt a(3) in cytochrome c oxidase, and the heterogeneous electron transfer rate constant obtained is 1.56 s(-1). By cyclic voltammetry measurements, it was observed that oxidation and reduction of cytochrome c in solution were catalyzed by the immobilized cytochrome c oxidase. This cytochrome c oxidase/MPA/Au system provides a good mimetic model to study the physiological functions of membrane-associated enzymes and hopefully to build a third-generation biosensor without using a mediator.