Better Junction Control with Bus Priority

The problem was to design a traffic light controller for a set of neigh- bouring junctions, which gives priority to incoming buses while ensuring a degree of fairness to the general traffic. The team has developed three complementary approaches, that present different strengths and weaknesses and might be applicable in different junction configurations or traffic conditions: 1. A continuous-variable, discrete-time optimisation approach for de- termining the fraction of green time to give to each arm of a junc- tion during the next traffic light cycle, in order to minimise total weighted squared vehicle waiting times, with more weight on buses than on cars. 2. A piece-wise linear ordinary differential equation model of queue length dynamics on a junction arm, based on flux of vehicles into and out of that arm. 3. Adiscrete-variable,discrete-timeMarkovDecisionProcessapproach. The state of the system is comprised of vehicle queue lengths and the junction’s current stage. The action is to stay in the current stage or move to the next stage. An optimal policy minimises long run expected discounted weighted delay

Implementing the 2005 American Heart Association guidelines, including use of the impedance threshold device, improves hospital discharge rate after in-hospital cardiac arrest

OBJECTIVE: To determine the impact of the 2005 American Heart Association cardiopulmonary resuscitation (CPR) guidelines, including use of an impedance threshold device (ITD), on survival after in-hospital cardiac arrest. METHODS: Two community hospitals that tracked outcomes after in-hospital cardiac arrest pooled and compared their hospital discharge rate before and after implementing the 2005 American Heart Association CPR guidelines (including ITD) in standardized protocols. In CPR we used the proper ventilation rate, allowed full chest-wall recoil, conducted continuous CPR following intubation, and used an ITD. We compared historical control data from a 12-month period at St Cloud Hospital, St Cloud, Minnesota, to data from a subsequent 18-month intervention phase. We compared historical control data from a 12-month period at St Dominic Hospital, Jackson, Mississippi to a subsequent 12-month intervention phase. 507 patients received CPR during the study period. Patient age and sex were similar in the control and intervention groups. RESULTS: The combined hospital discharge rate for patients with an in-hospital cardiac arrest was 17.5% in the control group (n=246 patients), which is similar to the national average, versus 28% in the intervention group (n=261 patients) (P=.006, odds ratio 1.83, 95% CI 1.17-2.88). The greatest benefit of the intervention was in patients with an initial rhythm of pulseless electrical activity: 14.4% versus 29.7% (P=.014, odds ratio 2.50, 95% CI 1.15, 5.58). Neurological function (as measured with the Cerebral Performance Category scale) in survivors at hospital discharge was similar between the groups. CONCLUSIONS: Implementation of improved ways to increase circulation during CPR increased the in-hospital discharge rate by 60%, compared to historical controls in 2 community hospitals. These data demonstrate that immediate care with improved means to circulate blood during CPR significantly reduces hospital mortality from inhospital sudden cardiac arrest

Development of an in vitro diagnostic method to determine the genotypic sex of Xenopus laevis

A genotypic sex determination assay provides accurate gender information of individuals with well-developed phenotypic characters as well as those with poorly developed or absent of phenotypic characters. Determination of genetic sex for Xenopus laevis can be used to validate the outcomes of Tier 2 amphibian assays, and is a requirement for conducting the larval amphibian growth and development assay (LAGDA), in the endocrine disruptor screening program (EDSP), test guidelines. The assay we developed uses a dual-labeled TaqMan probe-based real-time polymerase chain reaction (real-time PCR) method to determine the genotypic sex. The reliability of the assay was tested on 37 adult specimens of X. laevis collected from in-house cultures in Eurofins EAG Agroscience, Easton. The newly designed X. laevis-specific primer pair and probe targets the DM domain gene linked-chromosome W as a master female-determining gene. Accuracy of the molecular method was assessed by comparing with phenotypic sex, determined by necropsy and histological examination of gonads for all examined specimens. Genotypic sex assignments were strongly concordant with observed phenotypic sex, confirming that the 19 specimens were male and 18 were female. The results indicate that the TaqMan® assay could be practically used to determine the genetic sex of animals with poorly developed or no phenotypic sex characteristics with 100% precision. Therefore, the TaqMan® assay is confirmed as an efficient and feasible method, providing a diagnostic molecular sex determination approach to be used in the amphibian endocrine disrupting screening programs conducted by regulatory industries. The strength of an EDSP is dependent on a reliable method to determine genetic sex in order to identify reversals of phenotypic sex in animals exposed to endocrine active compounds

Superfeminization as an effect of bisphenol A in \u3ci\u3eMarisa cornuarietis\u3c/i\u3e & Response from Forbes et al. to Oehlmann et al.

[Oehlmann et al.]: Recently, we had the opportunity to read two articles in volume 66 of Ecotoxicology and Environmental Safety. Forbes et al. (2007a, , 2007b) declare “to explore the reproducibility of prior work” showing that bisphenol A (BPA) induces superfeminization in the freshwater snail Marisa cornuarietis (Oehlmann et al., 2000, 2006; Schulte- Oehlmann et al., 2001). Based on the outcome of a toxicity test with the same species, the authors conclude that their results “do not support previous claims of enhanced reproduction in M. cornuarietis in response to exposure to BPA.” We take issue with the declaration of exploring the reproducibility of our challenged work and the validity of the conclusions made by Forbes et al. (2007a, 2007b). Furthermore, we feel the toxicity test is flawed because its experimental design and the selected exposure conditions result in an irresponsiveness of test animals to the tested compound. ... [Forbes et al.]:We thank the editor for giving us the opportunity to respond to Oehlmann et al.’s comments (Oehlmann et al., 2008) on our papers (Forbes et al., 2007a,b). In response to the criticisms of our studies we would first like to emphasize that it was not our aim to exactly repeat the experiments of Oehlmann and colleagues, but rather to produce robust and reproducible results that were statistically valid and that therefore could be used in the risk assessment of bisphenol A (BPA). We are disturbed by the highly speculative suggestion by Oehlmann et al. that we may have studied a different ‘cryptic’ species of Marisa cornuarietis, as there is no evidence to support such suggestion. Furthermore, the snails used in our studies were collected from a documented pristine field site and identified to species by Dr. Sharon File-Emperador from University of Puerto Rico, a recognized snail expert. They were reared for a known number of generations under tightly controlled and documented conditions. In contrast, the snails used in Oehlmann et al.’s studies (e.g., Oehlmann et al., 2006) came from the Dusseldorf Zoo (original site of field collection not indicated) and were periodically supplemented with snails from Florida (location not indicated). There is likewise very little information in the published studies about the culture and husbandry conditions of Oehlmann et al.’s snails, whereas a major portion of our research aimed to identify appropriate husbandry and culture conditions for M. cornuarietis. It is on the basis of such detailed study that our toxicity tests with BPA were conducted

Standard Neutrino Spectrum from B-8 Decay

We present a systematic evaluation of the shape of the neutrino energy spectrum produced by beta-decay of $^8$B. We place special emphasis on determining the range of uncertainties permitted by existing laboratory data and theoretical ingredients (such as forbidden and radiative corrections). We review and compare the available experimental data on the $^8$B$(\beta^+){}^8$Be$(2\alpha)$ decay chain. We analyze the theoretical and experimental uncertainties quantitatively. We give a numerical representation of the best-fit (standard-model) neutrino spectrum, as well as two extreme deviations from the standard spectrum that represent the total (experimental and theoretical) effective $\pm3\sigma$ deviations. Solar neutrino experiments that are currently being developed will be able to measure the shape of the $^8$B neutrino spectrum above about 5 MeV. An observed distortion of the $^8$B solar neutrino spectrum outside the range given in the present work could be considered as evidence, at an effective significance level greater than three standard deviations, for physics beyond the standard electroweak model. We use the most recent available experimental data on the Gamow--Teller strengths in the $A=37$ system to calculate the $^8$B neutrino absorption cross section on chlorine: $\sigma_{\rm Cl}=(1.14\pm0.11)\times10^{-42}$~cm$^2$ ($\pm3\sigma$ errors). The chlorine cross section is also given as a function of the neutrino energy. The $^8$B neutrino absorption cross section in gallium is $\sigma_{\rm Ga}=(2.46^{+2.1}_{-1.1})\times10^{-42}$ cm$^2$ ($\pm3\sigma$ errors).Comment: Revised version, to appear in Phys. Rev.

Microsc Microanal

Abstract A microcompressor is a precision mechanical device that flattens and immobilizes living cells and small organisms for optical microscopy, allowing enhanced visualization of sub-cellular structures and organelles. We have developed an easily fabricated device, which can be equipped with microfluidics, permitting the addition of media or chemicals during observation. This device can be used on both upright and inverted microscopes. The apparatus permits micrometer precision flattening for nondestructive immobilization of specimens as small as a bacterium, while also accommodating larger specimens, such as Caenorhabditis elegans, for long-term observations. The compressor mount is removable and allows easy specimen addition and recovery for later observation. Several customized specimen beds can be incorporated into the base. To demonstrate the capabilities of the device, we have imaged numerous cellular events in several protozoan species, in yeast cells, and in Drosophila melanogaster embryos. We have been able to documen

Assessment of an in vitro whole cigarette smoke exposure system: The Borgwaldt RM20S 8-syringe smoking machine

<p>Abstract</p> <p>Background</p> <p>There have been many recent developments of <it>in vitro </it>cigarette smoke systems closely replicating <it>in vivo </it>exposures. The Borgwaldt RM20S smoking machine (RM20S) enables the serial dilution and delivery of cigarette smoke to exposure chambers for <it>in vitro </it>analyses. In this study we have demonstrated reliability and robustness testing of the RM20S in delivering smoke to <it>in vitro </it>cultures using an in-house designed whole smoke exposure chamber.</p> <p>Results</p> <p>The syringe precision and accuracy of smoke dose generated by the RM20S was assessed using a methane gas standard and resulted in a repeatability error of ≤9%. Differential electrical mobility particle spectrometry (DMS) measured smoke particles generated from reference 3R4F cigarettes at points along the RM20S. 53% ± 5.9% of particles by mass reached the chamber, the remainder deposited in the syringe or connecting tubing and ~16% deposited in the chamber. Spectrofluorometric quantification of particle deposition within chambers indicated a positive correlation between smoke concentration and particle deposition. <it>In vitro </it>air-liquid interface (ALI) cultures (H292 lung epithelial cells), exposed to whole smoke (1:60 dilution (smoke:air, equivalent to ~5 μg/cm²)) demonstrated uniform smoke delivery within the chamber.</p> <p>Conclusions</p> <p>These results suggest this smoke exposure system is a reliable and repeatable method of generating and exposing ALI <it>in vitro </it>cultures to cigarette smoke. This system will enable the evaluation of future tobacco products and individual components of cigarette smoke and may be used as an alternative <it>in vitro </it>tool for evaluating other aerosols and gaseous mixtures such as air pollutants, inhaled pharmaceuticals and cosmetics.</p

Effects of food type, feeding frequency, and temperature on juvenile survival and growth of \u3ci\u3eMarisa cornuarietis\u3c/i\u3e (Mollusca: Gastropoda)

The present experiments are part of a larger study designed to investigate the influence of husbandry parameters on the life history of the ramshorn snail, Marisa cornuarietis, in order to identify suitable husbandry conditions for maintaining multi-generation populations in the laboratory for use in ecotoxicological testing. In this paper we focus on the effects of a combination of food types and feeding frequencies (i.e., the frequency with which the snails were offered food) on juvenile growth and survival at different temperatures. Offspring produced in the laboratory by wild specimens of M. cornuarietis, from Puerto Rico, were used to test the effects of three types of food (lettuce, alginate with fish food, alginate with snail mix) fed at three frequencies (given ad libitum on 4/4, 2/4, or 1/4 d) on juvenile survival and growth. The 4-d feeding regimens were repeated four times, giving a total of 16 d for the experiments. The experiments were conducted at two temperatures (22 and 25 degrees C) under a 12 h light:12 h dark photoperiod. Juvenile growth rates increased with increasing feeding frequency for all food types. The most rapid growth rates occurred in the high-frequency lettuce treatments and the slowest growth rates in the low-frequency lettuce and alginate with snail mix treatments. Juvenile snails grew faster at 25 degrees than at 22 degrees C, and mortality was about twice as high at the lower temperature. Growth rates were used to provide a rough estimate of time to maturity, which was determined to take about twice as long at 22 degrees than at 25 degrees C. The results showed that lettuce is the best food if supplied in abundance, but effects on growth are very dependent on feeding frequency and temperature. We conclude that 25 degrees C is a more appropriate temperature for maintaining populations than 22 degrees C, that lettuce provides a suitable food source, and that food should be supplied continuously for husbandry and toxicity testing of populations of M. cornuarietis

Does Bisphenol A Induce Superfeminization in \u3ci\u3eMarisa cornuarietis\u3c/i\u3e? Part II: Toxicity Test Results and Requirements for Statistical Power Analyses

This study presents results of the effects of bisphenol A (BPA) on adult egg production, egg hatchability, egg development rates and juvenile growth rates in the freshwater gastropod, Marisa cornuarietis. We observed no adult mortality, substantial inter-snail variability in reproductive output, and no effects of BPA on reproduction during 12 weeks of exposure to 0, 0.1, 1.0, 16, 160 or 640 μg/L BPA. We observed no effects of BPA on egg hatchability or timing of egg hatching. Juveniles showed good growth in the control and all treatments, and there were no significant effects of BPA on this endpoint. Our results do not support previous claims of enhanced reproduction in Marisa cornuarietis in response to exposure to BPA. Statistical power analysis indicated high levels of inter-snail variability in the measured endpoints and highlighted the need for sufficient replication when testing treatment effects on reproduction in M. cornuarietis with adequate power