MAJOR IDEAS IN THE HISTORY OF AGRICULTURAL FINANCE AND FARM MANAGEMENT

This paper contains two articles that discuss major ideas from the history of agricultural finance and farm management. The agricultural finance article focuses on ideas that emerged prior to 1960. These ideas are classified into those emerging from action and scientific-framing eras. The second article characterizes the evolution of farm management and production economics from its beginnings in about 1900 to the start of the 21st century. Emphasis is placed on the melding of ideas from agriculturalists and economists.Agricultural finance, farm management, production economics, Agricultural Finance,

A high-speed optical star network using TDMA and all-optical demultiplexing techniques

The authors demonstrate the use of time-division multiplexing (TDM) to realize a high capacity optical star network. The fundamental element of the demonstration network is a 10 ps, wavelength tunable, low jitter, pulse source. Electrical data is encoded onto three optical pulse trains, and the resultant low duty cycle optical data channels are multiplexed together using 25 ps fiber delay lines. This gives an overall network capacity of 40 Gb/s. A nonlinear optical loop mirror (NOLM) is used to carry out the demultiplexing at the station receiver. The channel to be switched out can be selected by adjusting the phase of the electrical signal used to generate the control pulses for the NOLM. By using external injection into a gain-switched distributed feedback (DFB) laser we are able to obtain very low jitter control pulses of 4-ps duration (RMS jitter <1 ps) after compression of the highly chirped gain switched pulses in a normal dispersive fiber. This enables us to achieve excellent eye openings for the three demultiplexed channels. The difficulty in obtaining complete switching of the signal pulses is presented. This is shown to be due to the deformation of the control pulse in the NOLM (caused by the soliton effect compression). The use of optical time-division multiplexing (OTDM) with all-optical switching devices is shown to be an excellent method to allow us to exploit as efficiently as possible the available fiber bandwidth, and to achieve very high bit-rate optical networks

Advanced optimal extraction for the Spitzer/IRS

We present new advances in the spectral extraction of point-like sources adapted to the Infrared Spectrograph onboard the Spitzer Space Telescope. For the first time, we created a super-sampled point spread function of the low-resolution modules. We describe how to use the point spread function to perform optimal extraction of a single source and of multiple sources within the slit. We also examine the case of the optimal extraction of one or several sources with a complex background. The new algorithms are gathered in a plugin called Adopt which is part of the SMART data analysis software.Comment: Accepted for publication in PAS

The place of the family firm in a traditional industry undergoing rapid social, economic and technological change: an investigation into some of the problems faced by family firms in the British printing industry

Part 1 of the thesis traces the development of family firms and describes some of their characteristics. It examines problems of change facing business organisations generally at the present time and describes some of the ways in which these are likely to be particularly acute in family owned concerns. It concludes by considering the relevance of organisational theory to these problems. Part 2 describes the research methodology adopted for the study and its rationale. Part 3 is a description of the British printing industry—the industry in which the work was carried out. Part 4 contains comparative studies of firms which were selected by the investigator to represent family firms at various stages of development. This section ends with an analysis of the ways in which the six firms concerned were coping with the changes they faced. The conclusions include an examination of the role of the family firm in contemporary society and offers some suggestions for ways in which such enterprises can meet the challenge of change

Biomedical Terminologies and Ontologies: Enabling Biomedical Semantic Interoperability and Standards in Europe

In the management of biomedical data, vocabularies such as ontologies and terminologies (O/Ts) are used for (i) domain knowledge representation and (ii) interoperability. The knowledge representation role supports the automated reasoning on, and analysis of, data annotated with O/Ts. At an interoperability level, the use of a communal vocabulary standard for a particular domain is essential for large data repositories and information management systems to communicate consistently with one other. Consequently, the interoperability benefit of selecting a particular O/T as a standard for data exchange purposes is often seen by the end-user as a function of the number of applications using that vocabulary (and, by extension, the size of the user base). Furthermore, the adoption of an O/T as an interoperability standard requires confidence in its stability and guaranteed continuity as a resource

From Power-Localized to Extended States in a Class of One-Dimensional Disordered Systems

We study a one-dimensional random Kronig-Penney model in the presence of a constant electric field. We rigorously prove for the first time the existence of a transition between a regime of extended states for large field and a regime of power-localized states for small field. There the large-distance behavior of the states is |x|^(−α(F)) with α(F) ∼ C/F for small field F, confirming a numerical computation of Soukoulis et al

Injection seeded, diode pumped regenerative ring Nd:YAG amplifier for spaceborne laser ranging technology development

A small, all solid state, regenerative ring amplifier designed as a prototype for space application is discussed. Novel features include dual side pumping of the Nd:YAG crystal and a triangular ring cavity design which minimizes the number of optical components and losses. The amplifier is relatively small (3 ns round trip time) even though standard optical elements are employed. The ring regeneratively amplifies a 100 ps single pulse by approximately 10(exp 5) at a repetition rate of 10 to 100 Hz. The amplifier is designed to be injection seeded with a pulsed, 100 ps laser diode at 1.06 microns, but another Nd:YAG laser system supplying higher pulse energies was employed for laboratory experiment. This system is a prototype laser oscillator for the Geoscience Laser Ranging System (GLRS) platform. Results on measurements of beam quality, astigmatism, and gain are given

Systematic 1/M Expansion for Spin 3/2 Particles

Starting from a relativistic formulation of the pion-nucleon-delta system, the most general structure of 1/M corrections for a heavy baryon chiral lagrangian including spin 3/2 resonances is given. The heavy components of relativistic nucleons and delta fields are integrated out and their contributions to the next-to-leaing order lagrangians are constructed explicitly. The effective theory obtained admits a systematic expansion in terms of soft momenta, the pion mass $m_\pi$ and the delta-nucleon mass difference $\Delta$. As an application, we consider neutral pion photoproduction at threshold to third order in this small scale expansion.Comment: Revised version of original submissio

Murine mesenchymal stem cells suppress dendritic cell migration, maturation and antigen presentation

Mesenchymal stem cells (MSC) possess a wide range of immunosuppressive functions. Among these is the ability to inhibit CD4+ T cell proliferation. Dendritic cells (DC) play a role in initiating cell-mediated immunity; however, the immunosuppressive influence of MSC on professional antigen presenting cells remains unclear.DC exposed to TNF- and cultured with murine MSC failed to show regular upregulation of maturation markers. Similarly, the presence of MSC abrogated the capacity of ovalbumin-pulsed DC to support antigen specific CD4+ T cell proliferation, or for DC to display an MHC class II- peptide complex recognizable by specific antibody. Interestingly, culture of MSC with DC resulted in reduced expression of CCR7 by DC following stimulation. Likewise, DC matured in the presence of MSC, showed significantly less migration to CCL19. In contrast, murine MSC prevented loss of expression of the tissue anchoring protein E-cadherin by DC. Modulation of DC maturation and function was not permanent and could be restored after removal of MSC. These data demonstrate that MSC modulate the three cardinal features of DC maturation, providing the first demonstration of MSC interference with DC migratio