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Objective Many observational studies have demonstrated an association between preoperative anemia and adverse outcomes after cardiac surgery. However, there is a paucity of data on the impact of anemia in patients undergoing cardiac surgeries for rheumatic heart disease (RHD). This study was designed to examine the prevalence and impact of preoperative anemia in patients undergoing cardiac surgery for RHD. Design Retrospective observational data analysis. Setting Tertiary-care hospital. Participants 335 consecutive patients undergoing cardiac surgery for RHD from January 2009 to November 2014. Interventions No interventions. Measurements and Main Results Prevalence of preoperative anemia as per World Health Organization (WHO) definition was 51.95%. Mild and moderate anemias were present in 33.15% and 18.80%, respectively. The primary endpoint was in-hospital mortality, with an incidence of 26 (6.9%); the incidence of mortality in non-anemic, mildly anemic, and moderately anemic patients was 5.59%, 4.50%, and 19.04% (p = 0.003), respectively. Patients with moderate anemia utilized an average of 3 units of packed cells compared to 1 in non-anemic patients (p = 0.0001). A multiple regression analysis was performed to predict mortality from variables including anemia, EuroSCORE II, and perioperative blood transfusion. On adjusting for EuroSCORE II and severity of anemia, perioperative packed cell transfusion was associated with significant odds (odds ratio 2.218; confidence interval 1.517-2.986; p Conclusions In patients undergoing cardiac surgery for RHD, there was high prevalence of preoperative anemia. Despite higher transfusion rates in moderately anemic patients, they had significantly lower Hb on CPB and in the postoperative period. Perioperative packed cell transfusion was associated significantly with mortality.

The Australian sugar industry is seeking to increase profitability through better integration across a value chain fragmented among many owners. Within the cane harvesting and transport sectors, many existing inefficiencies are a result of excessive numbers of harvesting machines owned by harvester contractors and growers, and the fact that most harvesters operate within a short time window each day. In order to improve the complex system from a tactical and strategic planning perspective, leading to reduced costs of production, a modelling framework identifying the key drivers and links must first be developed. Upon developing the framework, techniques in operations research, financial modelling, and simulation can be applied to investigate opportunities to enhance the system in partnership with industry. This paper describes the development of such a framework through participation with two case-study mill areas within the Australian sugar industry, along with its application to improve the efficiency of the harvesting and transport system. Through reducing the number of harvesters in the region and implementing best practice principles for harvesting, one of the case study mills showed potential gains in profitability of up to AU$1 million per annum. Implementation took place in one of the case study regions during the 2003 harvest season for which the region is now pursuing further adoption in 2004.

Abstract The Gulfstar® FPS utilizes a standard Classic spar hull form (full depth, cylindrical hull) with a significantly shallower draft than previous Classic spars. Vortex Induced Motion (VIM) is a well-known but complicated phenomenon for cylindrical hulls and model testing is still the norm to determine the platform's VIM response characteristics. Towing-type tests are widely accepted and employed for VIM model tests; however this test method only simulates a uniform current profile with depth. In the actual ocean environment, only sheared currents are present so the tow test method over-predicts the loading on the cylinder from current, particularly in the deeper portions of the hull. To achieve more realistic test results for VIM testing, it is desirable to use sheared currents, especially for deep draft floaters, such as a Classic spar. Recent advancements in generating good quality sheared currents involve using a Flume Tank where the model is stationary and the water flows past with its velocity varied with depth. This paper describes a recent test program using this technology in a Flume Tank to explore effects of sheared currents on the VIM response characteristics of the Gulfstar® FPS. In addition to the capability of generating sheared currents, the Flume Tank, completely removes the constraints of towing tank length and the number of realizations for each test case. For benchmarking purposes, a uniform current is also generated in Flume Tank. Distinct VIM responses have been observed in both types of current profiles. These findings are presented and discussed in this paper. The value for the offshore industry from better predictions of VIM responses using model tests would be hard to overestimate. Being able to test using sheared currents is a valuable step toward obtaining more accurate test results for VIM type responses. Introduction The Gulfstar FPS® is a standard floater solution for the Gulf of Mexico region. The Gulfstar hull has a diameter of 25.9m (85ft) and a draft of 159.7m (524ft) making it much smaller as compared to other classic Spars in the Gulf of Mexico. Cylindrical structures such as Spars are known to exhibit Vortex Induced Vibration (VIV) or Vortex Induced Motions (VIM). VIM has increasingly become critical to the design of riser and mooring system. Low frequency fatigue in mooring system and risers due to VIM often drives the design of riser and mooring systems. Even though VIV has been investigated extensively over past three decades, prediction tools for VIV/VIM response of various systems are still very limited. Model testing is still the industry standard for determining the VIM performance of floaters. VIM is also observed on column stabilized units such as TLPs and Semi-submersibles [18], though not as significant as Spars.

The roles of statutory marketing authorities (SMAs) in agricultural sectors of developing countries are increasingly coming under scrutiny. Some countries have even begun to dismantle such institutions, or at least restrict their operations and powers. It is timely, therefore, to review the background and performance of these authorities, as a prelude to an assessment of their possible future role in agricultural development. A wide sample of documentary evidence is assembled containing evidence on the performance of statutory marketing authorities in developing country agriculture. Activities of the various authorities have been examined in both the food and export cash crop markets. It is concluded that there is little evidence that SMAs have achieved significant improvement in most marketing functions, and a good deal of evidence that they have worsened marketing performance. These findings raise fundamental questions about their future status as vehicles for agricultural development.

The project described in the paper is the first attempt to provide an economic evaluation of export-crop research in PNG. The institutional framework is outlined to provide a context for understanding the methods used. Past performance of two agricultural research projects was assessed and then eleven ex ante research evaluations were performed. After reviewing the overall results, suggestions are made for institutionalising research evaluation procedures at various levels of the public administration system.

The prevailing state of the art of ex-ante analysis of agricultural research is not well suited for project-level studies. The use of models lacking in sufficient detail is perceived as one of the weaknesses. A model of the development and adoption of a new agricultural technology that features technological progress in the without-project case is presented in a form that can be used for research project analysis in the planning stage.

The roles of planning and managing rural development projects have been the subject of many books and articles over the past decade. Some of the literature in this field has been in the domain of information gathering for rural development planning. Most studies, and prescriptions offered, tend to be ad hoc in nature. In this paper, an assessment is made of the prospects for a systematic approach to information gathering for rural development projects in less developed countries, based on the use of management information systems commonly associated with large Western commercial institutions.

A single-mode optical-fibre electrically tunable switch has been successfully fabricated. It consists of an interferometer constructed by consecutive fabrication of two couplers in tandem. Tunable power transfer in the output arms was achieved by the thermo-optic effect. Fabrication and performance details are described. The possible application of this device as a low-speed modulator is also considered.

Tapering of single-mode optical fibers has attracted much attention, since high-quality and low-cost fiber devices can be made in this manner. Optical fiber coaxial couplers1 have the waveguides, I.e., the core and secondary cladding coupled coaxially. Due to dissimilar geometry, phase matching does not always naturally occur, but it can be achieved with tapering. The coupling effects observed1 can be used for fabricating narrow passband filters.2

A single-mode optical-fibre switch which is electrically activated has been fabricated. This device is achieved by forming two couplers in series on a pair of single-mode optical fibres to provide a compact Mach-Zehnder interferometer (MZI). Power switching in the output arms is achieved by introducing a phase shift or path difference in the MZI by various means. The application of the device as a wavelength-selective switch is also considered.

The effect of twisting and longitudinal strain on the wavelength response of taper coaxial coupler filters is examined. Both effects permit the fine-tuning of the wavelength response of the single fibre filters, but we demonstrate that a combination of twist and strain is preferred, as it is possible to eliminate residual birefringence present during the fabrication of such filters.

The wavelength-dependent transmission characteristics of biconical tapers fabricated from single-mode fibres of depressed cladding are examined. The wavelength response is found to be oscillatory with large modulation depths. We describe here a simple fabrication technique which produces narrow passband filters of low loss and high extinction ratio (>30dB).

A single-mode fibre-optic wavelength-division multiplexer/demultiplexer with excellent isolation is reported. The device utilises a fused biconical structure similar to that of 3 dB couplers and exhibits an insertion loss of 0.04 dB and a wavelength isolation of 43 dB at 1.300 ?m and 30 dB at 1.523 ?m.

The variation of transmitted power through tapered coaxial couplers is presented as a function of the surrounding refractive index. This response allows us to select suitable cladding materials for the tapers that would desensitize their performance to environmental changes. Further, the use of tapers as refractive-index sensors is outlined.