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Clostridium difficile infection (CDI) places a high burden on the US healthcare system. Recurrent CDI (RCDI) occurs frequently. Recently proposed guidelines from the American College of Gastroenterology (ACG) and the American Gastroenterology Association (AGA) include fecal microbiota transplantation (FMT) as a therapeutic option for RCDI. The purpose of this study was to estimate the cost-effectiveness of FMT compared with vancomycin for the treatment of RCDI in adults, specifically following guidelines proposed by the ACG and AGA.
We constructed a decision-analytic computer simulation using inputs from the published literature to compare the standard approach using tapered vancomycin to FMT for RCDI from the third-party payer perspective. Our effectiveness measure was quality-adjusted life years (QALYs). Because simulated patients were followed for 90 days, discounting was not necessary. One-way and probabilistic sensitivity analyses were performed.
Base-case analysis showed that FMT was less costly ($1,669 vs $3,788) and more effective (0.242 QALYs vs 0.235 QALYs) than vancomycin for RCDI. One-way sensitivity analyses showed that FMT was the dominant strategy (both less expensive and more effective) if cure rates for FMT and vancomycin were ≥70% and <91%, respectively, and if the cost of FMT was <$3,206. Probabilistic sensitivity analysis, varying all parameters simultaneously, showed that FMT was the dominant strategy over 10, 000 second-order Monte Carlo simulations.
Our results suggest that FMT may be a cost-saving intervention in managing RCDI. Implementation of FMT for RCDI may help decrease the economic burden to the healthcare system.
Garlic mustard is among the most important invasive weeds of North American eastern deciduous forests. Investigations of the mechanisms that enable its success as an invader require a simple method to propagate this weed in the laboratory and the greenhouse; we develop such a method in this study. Cold treatment (24-h dark cycle; maximum 6 C, minimum −1 C) for at least 100 d on a moist organic mix, followed by incubation at temperatures approximating spring (maximum 15 C, minimum 6 C), results in close to 100% germination. The information presented here will be valuable in studies requiring a steady supply of garlic mustard plants for experimentation and for the mass rearing of biological control agents.
Direct re-implantation of an anomalous left coronary artery into the aorta is the preferred surgical option for creating a dual coronary arterial system in patients in whom the anomalous artery originated from the pulmonary trunk. This technique, however, is applicable only when the anomalous artery arises from the right posterior pulmonary sinus. We report a new technique for re-implantation using combined autogenous aortic and pulmonary arterial flaps in situations when a direct connection was not possible.
Patients and methods
We have treated 4 patients, aged 3 months, 6 months, 18 months, and 27 years respectively, who presented with anomalous origin of the left coronary artery from the left posterior pulmonary sinus. We used our proposed technique for transfer because lack of coronary arterial length, diminished vessel elasticity, and extensive collaterals around the pulmonary sinuses prevented direct attachment.
There was no early or late death. Postoperatively, all patients are in functional class I, with good biventricular function at a median follow-up of 74 months, with a range from 9 to 96 months. Postoperative coronary angiography in our 4th patient showed good arterial flow, without any distortion.
The potential benefits of this modification of the trapdoor technique are excellent operative exposure, use of autogenous and viable tissue capable of further growth, avoidance of injury to the aortic and pulmonary valvar apparatus and production of obstruction within the right ventricular outflow tract, complete elimination of use of pericardium for augmentation of the neo-aortic tube, achievement of the anastomosis with correct angling and length, and the possibility of implantation in all patients, including adults, regardless of the distance from the aorta or the coronary arterial configuration.
The Chinese citrus fruit fly, Bactrocera (Tetradacus) minax (Enderlein), is one of the major citrus pests in Bhutan and can cause >50% mandarin (Citrus reticulata Blanco) fruit drop. As part of the development of a management strategy for the fly in mandarin orchards, population monitoring and experimental manipulations were carried out to determine: (i) adult emergence period; (ii) adult phenology patterns; (iii) period of crop susceptibility; and (iv) period from fruit drop to pupation. In western Bhutan, adult flies emerge from the overwintering pupal stage in late April/early May. Most flies are mature by the end of May and it is inferred that mating occurs at this time: from the beginning of June males rapidly disappear from the population and by mid- to late June are rare or absent from traps. Mature females are present in the mandarin crop at the beginning of June, but very little oviposition occurs until mid-June, while most damage has occurred by mid-July. Initiation of oviposition into mandarins is almost certainly linked to crop phenology. Adult flies disappear from the orchard system during August. After fruit drop, larvae were recorded leaving the fruit to pupate within 13 days. The use of early to mid-season protein bait sprays and/or targeted use of systemic insecticides during the one month oviposition period, plus the removal of fallen fruit once every 10 days, are recommended as control strategies.
This paper presents a new approach to vectoring jet thrust using a miniature fluidic actuator that provided spatially distributed mass addition. The fluidic actuators used had no moving parts and produced oscillatory flow with a square wave form at frequencies up to 1·6kHz. A subsonic jet with an exit diameter of 3·81cm was controlled using single and dual fluidic actuators, each with an equivalent circular diameter of 1·06mm. The fluidic nozzle was operated at pressures between 20·68 and 165·47kPa. The objectives of the present work included documentation of the actuation characteristics of fluidic devices, assessment of the effectiveness of fluidic devices for jet thrust vectoring, and evaluation of mass flow requirements for vectoring under various conditions. Measurements were made in the flow field using a pitot probe for the vectored and unvectored cases. Some acoustic measurements were made using microphones in the near-field and for selected cases particle image velocimetry (PIV) measurements were made. Thrust vectoring was obtained in low speed jets by momentum effects with fluidic device mass flow rates of only 2 × 10–4kg/sec (0·6% of main jet mass flow per fluidic oscillator). Although a single fluidic device produced vectoring of the primary jet, the dual fluidic device configuration (with two fluidic devices on either side of the jet exit) produced mass flux enhancement of 28% with no vectoring. Our results indicate that fluidic actuators have the potential for use in thrust vectoring, flow mixing and industrial flow deflection applications.
While lures of plant origin are vital tools in dacine (Diptera: Tephritidae) pest management, the ecological and evolutionary significance of this lure response remains enigmatic. Two hypotheses (the ancestral host hypothesis and sexual selection by female choice) have been invoked to explain the functional significance of these chemicals to dacine fruit flies. These hypotheses are often treated as alternatives to one another and evidence favouring one is used to reject the other. This review highlights that these two hypotheses are not logical alternatives to each other as the ancestral host hypothesis attempts to explain the ultimate function of the response of Dacinae to these plant-derived parapheromones while the sexual selection hypothesis provides a proximate explanation for lure response. Research on lure response, dacine mating behaviour, functional significance of lures, plant phylogeny and biochemistry and dacine pheromone chemistry are used to evaluate the evidence in relation to both these hypotheses. Some of the key findings are that there is evidence both in support of and against these two hypotheses. Response of fruit flies to related phenyl propanoids to those commonly used as lures in pest management and distribution of phenyl propanoids attractive to dacines among plant orders strongly support the ancestral host hypothesis. Evidence from pheromone chemistry, dacine mating behaviour and the functional significance of lures both support and contradict the sexual selection hypothesis. Lures appear to have different proximate functions in different dacine species. Considerably greater research is needed to clarify the functional role of phytochemical lures to dacine fruit flies. The two prevalent hypotheses should be investigated independently. Specific research on dacine phylogeny and distribution of lures in plants in relation to ecological roles played by adult dacines is required to elucidate the ultimate roles of the chemicals. Exploration of female response to lures and the behavioural consequences of dacine response to these chemicals to both the insect and plant may shed light on the proximate functions of these chemicals.
The highest efficiency CuIn1-xGaxSe2 (CIGS) solar cells use thin-film polycrystalline CIGS absorber layers. We have applied variable angle spectroscopic ellipsometry (VASE) to characterize the dielectric functions of polycrystalline thin films of CIGS with Ga: (In + Ga) ratios ranging from 0.18 to 1.0. The Cu: (In + Ga) ratios in these films are approximately 0.90, which is the ratio that yields the highest efficiency CIGS devices. Spectra were measured over the energy range 0.7 to 5.0 eV at room temperatures. Models used to analyze the ellipsometry data include the full multi-layer structure of the sample, which enables us to report the actual dielectric function rather than the pseudo-dielectric function. We present data on how the critical points change with composition, and compare and contrast our results with measurements of single-crystal and bulk polycrystalline samples reported in the literature. Auger electron spectroscopy, atomic force microscopy, and X-ray diffraction have been used to verify the homogeneity, surface roughness, and phase purity, respectively.
Previously we reported on a two-layer electrodeposition process of thallium oxide superconductors that showed transport critical current density above 106 A/cm2 at 77 K in zero field. In this article, we report our effort to convert an electrodeposited thick film of (Tl,Bi,Pb)2(Sr,Ba)2Ca1Cu2Ox to (Hg,Bi,Pb)2(Sr,Ba)2Ca1Cu2Ox by the cation-exchange process. We are also reporting magneto-optical imaging data on Tl oxide superconductor films, which are compared with YBCO. Magneto-optical imaging provides insight into the nature of current flow in the Tl oxide superconductor, and thus, will help us to improve the critical current density in bulk high-temperature superconductor wire or tape.
Quantitative studies on marine Phycomycetes (thraustochytrids) were carried out at 6 stations between the Fladenground area of the North Sea and the mouth of the River Tay, between September 1975 and September 1976. Five samplings were made of the surface water and the sediment during this period. The number of fungi/litre sea water or sediment increased with the proximity to the mouth of the river compared to the high seas. The fungal population exhibited a seasonal fluctuation, a high number occurring in September and an extremely low number occurring in March. The sediments revealed a very high number of propagules/litre (up to 73,000) compared to the water (up to 384).
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