A Two-dimensional (2D) Periodic Surface Lattice (PSL) can produce distributed feedback in high power microwave sources driven by an oversized electron beam of annular geometry. Such 2D periodic ...structures can be formed in cylindrical waveguide with a grating machined on the walls, where the diameter of the waveguide is larger than the wavelength λ (D >> λ). In this case localised surface fields can be excited around the perturbations if the structure is radiated by an external source (for example an electron beam). Experiments were conducted using a velvet cathode electron gun with the electron accelerating voltage produced by a cable Blumlein generator. "Additive Manufacturing" or "3D printing" was used to construct a silver 2D PSL quickly, efficiently and relatively inexpensively. The electron beam formed within an 18 mm bore 1.8 T solenoid was transported through the 7.2 mm inner diameter silver 2D PSL beam-wave interaction region. An 80 kV, 100 A electron beam with an outer diameter of 4 mm and inner diameter of 2mm which was approximately 1.8 mm away from the inner surface of the 2D PSL corrugation was measured. Millimetre wave radiation at a frequency of ~80GHz at an output power of 130 ± 30 kW corresponding to an operating efficiency of ~1.7 % was measured.
In economics, the number of observations available for empirical work is often predetermined. Researchers assume some large sample distribution and carry through with measurement and testing applied ...to data sets of varying sizes. The consequences of sampling variability are generally ignored. It is shown in a re-sampling experiment, using data sets of different sizes and estimating log-linear male labour supply equations, that a wide range of what appears to be statistically supported estimates of the wage elasticity of labour supply are generated. Testing based on bootstrapped estimates shows that 4000 observations are required to reduce sampling variability to statistically acceptable levels.
Experimental results from the operation of an electron beam driven, mm-wave, vacuum electronic source are reported. The aim of this work is to create improved electron-beam-driven, vacuum electronic ...mm-wave and sub-THz sources by exploiting dispersion-engineering. Dispersion-engineered structures can be manufactured by several techniques and in this work additive manufacturing has proven to be quick, reliable and cost-effective.
The goal of this article is to introduce organizational identification and self-monitoring as potential moderators in the relationship between proactive personality and the transfer of learning. ...Training investments often fail to deliver the desired and expected outcome and it has been reported that despite the vast amounts of money organizations spend on employee training, only 10 to 15% of it is transferred back to the workplace. This article offers an explanation of the training transfer phenomenon and helps determine whether moderators facilitate or inhibit the learning transfer process. The article proposes that self-monitoring and organizational identification moderate the effects of personality on learning transfer and facilitates the learning transfer process because individuals who are high self-monitors may want to demonstrate all that they have learned in the training program in order to impress their co-workers, and boss; and individuals who strongly identifies with a firm are concerned with its well being and will ensure that they learn and transfer the training back to the workplace to ensure that their organization performs effectively. Finally, several guidelines for practitioners are considered. PUBLICATION ABSTRACT
Summary
The value of continuous electrocardiogram recording in the peri‐operative period has been examined. In a group of 15 patients. 14 developed changes two of which persisted into the ...postoperative period. Dysrhythmias, ST segment and T‐wave changes occurred frequently. Continuous recording is of potential benefit in the study of cardiovascular disease and therapy in the peri‐operative period.
Participation in adult education and adult learning are two important areas of research as more and more adults seek learning opportunities, via academic institutions or organizational training ...programs, in their quest to achieve their various goals. Thus, it is important that educational (and business) leaders are aware of the dynamics surrounding the learning process of the "older generation" so that reasonable steps can be taken to facilitate their success in acquiring and retaining required and/or desired knowledge and skills. Numerous factors play a role in individuals' decision to participate in adult education and in the learning process they experience. This paper will investigate the influence of age, ability and self efficacy on adults' intentions to learn and actual learning from educational/training programs. A conceptual model, implications for educators and educational leaders, and suggestions for future inquiry will also be presented. PUBLICATION ABSTRACT
We present the design and performance of a simple fixed-frequency superconducting lumped-element resonator developed for axion and hidden photon dark matter detection. A rectangular NbTi inductor was ...coupled to a Nb-coated sapphire capacitor and immersed in liquid helium within a superconducting shield. The resonator was transformer-coupled to a DC SQUID for readout. We measured a quality factor of \(\sim\)40,000 at the resonant frequency of 492.027 kHz and set a simple exclusion limit on \(\sim\)2 neV hidden photons with kinetic mixing angle \(\varepsilon\gtrsim1.5\times10^{-9}\) based on 5.14 hours of integrated noise. This test device informs the development of the Dark Matter Radio, a tunable superconducting lumped-element resonator which will search for axions and hidden photons over the 100 Hz to 300 MHz frequency range.
The application of equilibrium dialysis to the determination of the "free", i.e. non-albumin bound fraction of human plasma or serum tryptophan has been re-examined. A potentially serious error in ...the application of this method is outlined and the necessary correction and some precautionary measures are discussed.
The chemically averaged molecular weights of a variety of native and conjugated monoclonal antibodies, approximately 150,000, were measured by matrix-assisted UV-laser desorption/ionization mass ...spectrometry. The average mass of the carbohydrate present in a monoclonal antibody was estimated from the difference between the measured mass of the monoclonal antibody and the mass of the protein present in the monoclonal antibody computed from the amino acid translation of the DNA sequence. The loading of chelators and anticancer drugs conjugated to a monoclonal antibody was quantitated from the difference in the measured masses for the conjugated and untreated monoclonal antibody relative to the expected mass change upon conjugation of 1 mol of chelator or drug. The loading results obtained by mass spectrometry were consistent in most cases with measurements obtained by radioactivity trace assay or UV spectrometry. Similar matrix-assisted UV-laser desorption/ionization mass spectrometric studies were also made after reducing untreated and conjugated monoclonal antibodies with dithiothreitol to determine the distribution of carbohydrate and chelator between the light and heavy chains of the molecules. Matrix-assisted UV-laser desorption/ionization mass spectra were used to compute loading values for covalently bound drugs and proteins, while the loading values obtained by use of gel-filtration HPLC and UV spectrometry cannot distinguish between covalently and noncovalently bound drugs and proteins.
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