Development of a low-cost, electricity-generating Rankine cycle, alcohol-fuelled cooking stove for rural communities

This article describes a novel design and construction of a helical tube flash boiler that uses a 2kW nominal methylated spirit burner to heat an approximately 2.5m long coil of copper pipe fed by a nominal 8 bar electrically operated solenoid water pump. The final embodiment is for superheated steam to be converted to electricity and the waste exit heat from the generator used either for cooking or for ethanol pro duction for low-income families in developing countries. The performance of the flash boiler has been evaluated experimentally based on the well-known “Direct-Method”; by carefully measuring both the flow of the fuel and the steam. It found that the pressure inside the pipe can reach up to 7.4 bar and the temperature of the steam released by the flashing process can reach 255°C utilising a low-cost water pump. The research results prese nted in this paper demonstrate that flash boiler stove has a great potential for generating high-temperature steam for developing a low-cost cooking stove

The Influence of Heat Input Ratio on Electrical Power Output of a Dual-Core Travelling-Wave Thermoacoustic Engine

This paper presents an analytical and experimental investigation of an electricity generator that employs a two-stage looped tube travellin -wave thermoacoustic prime-mover to deliver acoustic power from heat energy, a loudspeaker to extract electricity from sound energy and a tuning stub to compensate the changes in the acoustic field within the engine to enable close to travelling wave operation at the loudspeaker. Furthermore, the paper explains how to enhance the output power utilizing different heat input ratios through the engine cores. A well-known thermoacoustic design tool called Delta EC is used to simulate the wave propagation through the different parts of the system. The electrical power predicted from the low-cost prototype was 24.4 W acoustic power which confirms the potential for developing low-cost thermoacoustic electricity generator for heat recov ery from low-grade heat sources. The electrical power can be increased to 31.3 W using different heating power percentages through the two units. The verified experimental data shows good agreement with DeltaEC results

Image-based measurement of alveoli volume expansion in an animal model of a diseased lung

Currently, there does not exist reliable MV treatment or protocols in critical care to treat acute respiratory diseases, and thus no proven way to optimise care to minimise the mortality, length of stay or cost. The overall approach of this research is to improve protocols by using appropriate computer models that take into account the essential lung mechanics. The aim of this research is to create an automated algorithm for tracking the boundary of individual or groups of alveoli, and to convert this into a pressure volume curve for three different types of alveoli. A technique called in vivo microscopy has been developed by Schiller et al which visualizes the inflation and deflation of individual alveoli in a surfactant deactivation model of lung injury in pigs. Three different types of alveoli were tracked using data from Schiller et al, type I, II and III. These types correspond to healthy alveoli, non-collapsing but partially diseased alveoli, and fully collapsing diseased alveoli respectively. The boundaries of all the alveoli that were tracked, compared well visually to the movies. Pressure versus Area curves were derived for both inflation and deflation, they captured the expected physiological behaviour, and were qualitatively similar to the quasi-static pressure area curves derived in Schiller et al, Quantitative differences are due to the dynamic effects of ventilation which were not investigated in Schiller et al

Analysis and comparison of nonlinear tree height prediction strategies for Douglas-fir forests

Using an extensive Douglas-fir data set from southwest Oregon, we examined the (1) performance and suitability of selected prediction strategies, (2) contribution of relative position and stand-density measures in improving tree height (h) prediction values, and (3) effect of different subsampling designs to fill in missing h values in a new stand using a regional nonlinear model. Nonlinear mixed-effects models (NMEM) substantially improved the accuracy and precision of height prediction over the conventional nonlinear fixed-effects model (NFEM) that assumes the observations are independent, particularly when a few trees are subsampled for height. The predictive performance of a correction factor on a NFEM with relative position and stand-density measures was comparable to that of a NMEM when four or more trees were subsampled for height. When two or more heights were randomly subsampled, the NMEM efficiently explained the differences in the height–diameter relationship because of the variations in relative position of trees and stand density without having to incorporate them into the model. When only one height was subsampled, selecting the largest diameter tree in the stand would result in a lower predicted root mean square error (RMSE) than randomly selecting the height, regardless of the model form or fitting strategy used.A` l’aide d’une banque de donne´es exhaustive sur le sapin Douglas du sud-ouest de l’Oregon, nous avons examine ´ (1) la performance et la pertinence des strate´gies de pre´diction se´lectionne´es, (2) la contribution de la position relative de l’arbre et de la densite´ du peuplement pour ame´liorer la pre´diction de la hauteur des arbres et (3) l’effet de diffe´rents dispositifs d’e´chantillonnage pour imputer la hauteur manquante dans un nouveau peuplement a` l’aide d’un mode`le non line´aire re´gional. Les mode`les non line´aires a` effets mixtes (MNLEM) ame´liorent substantiellement l’exactitude et la pre´cision des pre´dictions de la hauteur comparativement au mode`le non line´aire a` effets fixes conventionnel (MNLEF). Ce dernier suppose que les observations sont inde´pendantes, particulie`rement lorsque peu d’arbres sont e´chantillonne´s pour e´valuer la hauteur. La performance pre´dictive d’un facteur de correction pour le MNLEF base´ sur la mesure de la position relative de l’arbre et de la densite´ du peuplement est comparable a` celle du MNLEM lorsque quatre arbres ou plus sont e´chantillonne´s pour e´valuer la hauteur. Lorsque deux hauteurs ou plus sont e´chantillonne´es ale´atoirement, le MNLEM explique efficacement les diffe´rences dans la relation hauteur-diame`tre dues aux variations de la position relative des arbres et de la densite´ sans avoir a` les incorporer formellement dans le mode`le. Lorsqu’une seule hauteur est e´chantillonne´e, le choix du plus gros arbre dans le peuplement pourrait entraıˆner une erreur de pre´diction plus faible que lorsque la hauteur est se´lectionne´e au hasard, peu importe la forme du mode`le ou la strate´gie d’ajustement utilise´e

Evaluation of mixed-effects models for predicting Douglas-fir mortality

We examined the performance of several generalized linear fixed- and mixed-effects individual-tree mortality models for Douglas-fir stands in the Pacific Northwest. The mixed-effects models accounted for sampling and study design overdispersion. Inclusion of a random intercept term reduced model bias by 88% relative to the fixed-effects model; however, model discrimination did not substantially differ. An uninformed version of the mixed model that used only its fixed effects parameters produced predicted mortality values that exceeded the fixed-effects model bias by 31%. Overall, we did not find compelling evidence to suggest that the mixed models fit our data better than the fixed-effects model. In particular, the mixed models produced fixed-effects parameter estimates that predicted unreasonably high mortality rates for trees approaching 1 m in diameter at breast height.Keywords: Douglas-fir, Mortality, Generalized linear model, Mixed mode

POSTIRRADIATION EXAMINATION OF CENTRIFUGALLY BONDED EBR-11 DRIVER FUEL

BNW was requested by AEC/DRDT to assist ANL with the postirradiation examination of EBR-II driver fuel (U + 5Fs) pins that became shortened during irradiation. To date, three irradiated pins and one nonirradiated pin were examined

Height-diameter equations for six species in the coastal regions of the Pacific Northwest

Three equations for predicting tree height as a function of diameter (outside bark) at breast height are presented for six species found in coastal regions of the Pacific Northwest. Foresters can use these “height–diameter” equations to avoid the time-consuming task of measuring heights of all individual trees in an inventory, a stand exam, or a timber cruise. Equation coefficients were estimated with weighted nonlinear regression techniques. Because the relationship between a tree’s height and diameter depends on the tree’s competitive position within the stand, alternative equations, including the average height and average diameter of the 40 largest-diameter trees/ac, are also presented. These equations are used in the Stand Management Cooperative version of ORGANON

Repurposing tofacitinib as an anti-myeloma therapeutic to reverse growth-promoting effects of the bone marrow microenvironment.

The myeloma bone marrow microenvironment promotes proliferation of malignant plasma cells and resistance to therapy. Activation of JAK/STAT signaling is thought to be a central component of these microenvironment-induced phenotypes. In a prior drug repurposing screen, we identified tofacitinib, a pan-JAK inhibitor Food and Drug Administration (FDA) approved for rheumatoid arthritis, as an agent that may reverse the tumor-stimulating effects of bone marrow mesenchymal stromal cells. Herein, we validated in vitro, in stromal-responsive human myeloma cell lines, and in vivo, in orthotopic disseminated xenograft models of myeloma, that tofacitinib showed efficacy in myeloma models. Furthermore, tofacitinib strongly synergized with venetoclax in coculture with bone marrow stromal cells but not in monoculture. Surprisingly, we found that ruxolitinib, an FDA approved agent targeting JAK1 and JAK2, did not lead to the same anti-myeloma effects. Combination with a novel irreversible JAK3-selective inhibitor also did not enhance ruxolitinib effects. Transcriptome analysis and unbiased phosphoproteomics revealed that bone marrow stromal cells stimulate a JAK/STAT-mediated proliferative program in myeloma cells, and tofacitinib reversed the large majority of these pro-growth signals. Taken together, our results suggest that tofacitinib reverses the growth-promoting effects of the tumor microenvironment. As tofacitinib is already FDA approved, these results can be rapidly translated into potential clinical benefits for myeloma patients

Predicting height for undamaged and damaged trees in southwest Oregon

Equations for predicting tree height as a function of diameter outside bark at breast height are presented for various tree species common to southwest Oregon. Data for damaged and undamaged trees were analyzed with weighted nonlinear regression techniques. The effects of specific damaging agents and their severity on the height-diameter relationship were explored. Damage correction multipliers were estimated, then used to correct predicted height where damage was noted. Because the relationship between height and diameter changes with the competitive position of the tree in a stand, alternative equations are presented that include the average height and diameter of the 40 largest-diameter undamaged conifer trees per acre. Foresters can use these “height-diameter” equations to reduce the time-consuming task of measuring heights of every tree in an inventory, stand exam, or timber cruise. They can also use these equations to estimate the change in height as diameter changes. These equations will be incorporated into the new southwest Oregon version of ORGANON, which extends the model to older stands and stands with a heavier component of hardwood species

Modeling the Effects of Low Flow Augmentation by Discharge from a Wastewater Treatment Plant on Dissolved Oxygen Concentration in Leon Creek, San Antonio, Texas.

A GIS-based hydrological/water quality model called Non Point Source Model (NPSM) was used to simulate various physical, chemical and biological processes taking place in the Leon Creek Watershed, near San Antonio, Texas. The model was then used to evaluate base flow augmentation scenarios to remedy dissolved oxygen problems during dry, low-flow periods. The effects were demonstrated by increasing base flow in a stream by discharging recycled water from Leon Creek Wastewater Treatment Plant during a three month low-flow period in 1993, 1994 and 1995 respectively. Five scenarios were evaluated in addition to the control scenario (no flow augmentation). Each of the five scenarios represented an increase in base flow by a factor of 0.25, 0.5, 1, 2 and 4 respectively. The study indicated that increasing base flow in the stream increased the mean daily DO concentration in the stream. The most significant effect was observed when the base flow was increased by a factor of 1 onwards, with no data point falling below the DO criterion of 5 mg/l. From the results of DO modeling developed for this project iv and from the scenario analysis, it can be concluded that a minimum flow augmentation of one times base flow (i.e. doubling the base flow) is required in order to see a significant increase in mean daily DO concentration in Leon Creek and associated tributaries and remedy DO problems during low-flow periods. Since there is uncertainty involved in the modeling process, it is recommended that a higher flow augmentation of two times base flow or four times base flow be implemented in order to reduce uncertainty and significantly improve water quality of Leon Creek