Density-Enhanced Gas and Dust Shells in a New Chemical Model for IRC+10216

A new chemical model is presented for the carbon-rich circumstellar envelope (CSE) of the asymptotic giant branch star IRC+10216. The model includes shells of matter with densities that are enhanced relative to the surrounding circumstellar medium. The chemical model uses an updated reaction network including reactions from the RATE06 database and a more detailed anion chemistry. In particular, new mechanisms are considered for the formation of CN-, C3N-, and C2H-, and for the reactions of hydrocarbon anions with atomic nitrogen and with the most abundant cations in the CSE. New reactions involving H- are included which result in the production of significant amounts of C2H- and CN- in the inner envelope. The calculated radial molecular abundance profiles for the hydrocarbons C2H, C4H, and C6H and the cyanopolyynes HC3N and HC5N show narrow peaks which are in better agreement with observations than previous models. Thus, the narrow rings observed in molecular microwave emission surrounding IRC+10216 are interpreted as arising in regions of the envelope where the gas and dust densities are greater than the surrounding circumstellar medium. Our models show that CN- and C2H- may be detectable in IRC+10216 despite the very low theorized radiative electron attachment rates of their parent neutral species. We also show that magnesium isocyanide (MgNC) can be formed in the outer envelope through radiative association involving Mg+ and the cyanopolyyne species.

The massive neutron star or low-mass black hole in 2S 0921-630

We report on the optical spectroscopy of the eclipsing halo low-mass X-ray binary 2S 0921-630, which reveals the absorption-line radial velocity curve of the K0 III secondary star with a semiamplitude K-2=92.89+/-3.84 km s(-1), a systemic velocity gamma=34.9+/-3.3 km s(-1), and an orbital period P-orb of 9.0035+/-0.0029 days (1 sigma). Given the quality of the data, we find no evidence for the effects of X-ray irradiation. Using the previously determined rotational broadening of the mass donor and applying conservative limits on the orbital inclination, we constrain the compact object mass to be 2.0-4.3 M-circle dot (1 sigma), ruling out a canonical neutron star at the 99% level. Since the nature of the compact object is unclear, this mass range implies that the compact object is either a low-mass black hole with a mass slightly higher than the maximum possible neutron star mass (2.9 M-circle dot) or a massive neutron star. If the compact object is a black hole, it confirms the prediction of the existence of low-mass black holes, while if the object is a massive neutron star, its high mass severely constrains the equation of state of nuclear matter.

A competitive enzyme-linked immunosorbent assay for determination of chloramphenicol

Chloramphenicol is a broad-spectrum antibiotic shown to have specific activity against a wide variety of organisms that are causative agents of several disease conditions in domestic animals. Chloramphenicol has been banned for use in food-producing animals for its serious adverse toxic effects in humans. Due to the harmful effects of chloramphenicol residues livestock products should be free of any traces of these residues. Several analytical methods are available for chloramphenicol analysis but sensitive methods are required in order to ensure that no traces of chloramphenicol residues are present in edible animal products. In order to prevent the illegal use of chloramphenicol, regulatory control of its residues in food of animal origin is essential. A competitive enzyme-linked immunosorbent assay for chloramphenicol has been locally developed and optimized for the detection of chloramphenicol in sheep serum. In the assay, chloramphenicol in the test samples and that in chloramphenicol-horseradish peroxidase conjugate compete for antibodies raised against the drug in camels and immobilized on a microtitre plate. Tetramethylbenzidine-hydrogen peroxide (TMB/H2O2) is used as chromogen-substrate system. The assay has a detection limit of 0.1 ng/mL of serum with a high specificity for chloramphenicol. Cross-reactivity with florfenicol, thiamphenicol, penicillin, tetracyclines and sulfamethazine was not observed. The assay was able to detect chloramphenicol concentrations in normal sheep serum for at least 1 week after intramuscular injection with the drug at a dose of 25 mg/kg body weight (b.w.). The assay can be used as a screening tool for chloramphenicol use in animals.

Estimating the masses of extra-solar planets

All extra-solar planet masses that have been derived spectroscopically are lower limits since the inclination of the orbit to our line-of-sight is unknown except for transiting systems. In theory, however, it is possible to determine the inclination angle, i, between the rotation axis of a star and an observer's line-of-sight from measurements of the projected equatorial velocity (v sin i), the stellar rotation period (P(rot)) and the stellar radius (R(*)). For stars which host planetary systems this allows the removal of the sin i dependency of extra-solar planet masses derived from spectroscopic observations under the assumption that the planetary orbits lie perpendicular to the stellar rotation axis.
We have carried out an extensive literature search and present a catalogue of v sin i, P(rot) and R(*) estimates for stars hosting extra-solar planets. In addition, we have used Hipparcos parallaxes and the Barnes-Evans relationship to further supplement the R(*) estimates obtained from the literature. Using this catalogue, we have obtained sin i estimates using a Markov-chain Monte Carlo analysis. This technique allows proper 1 Sigma two-tailed confidence limits to be placed on the derived sin i's along with the transit probability for each planet to be determined.
While we find that a small proportion of systems yield sin i's significantly greater than 1, most likely due to poor P(rot) estimations, the large majority are acceptable. We are further encouraged by the cases where we have data on transiting systems, as the technique indicates inclinations of similar to 90 degrees and high transit probabilities. In total, we are able to estimate the true masses of 133 extra-solar planets. Of these 133 extra-solar planets, only six have revised masses that place them above the 13M(J) deuterium burning limit; four of those six extra-solar planet candidates were already suspected to lie above the deuterium burning limit before correcting their masses for the sin i dependency. Our work reveals a population of high-mass extra-solar planets with low eccentricities, and we speculate that these extra-solar planets may represent the signature of different planetary formation mechanisms at work. Finally, we discuss future observations that should improve the robustness of this technique.

Effects of Interface Conditions and Long-Term Stability of Passive Intermodulation Response in Printed Lines

An experimental investigation of the effect of conductor-to-substrate interface on distributed passive intermodulation (PIM) generation in printed microstrip lines has been undertaken using the custom-designed microwave laminates with removed surface bonding layers and with the commercial adhesion promotion applied to the conductor underside. The study of long-term stability of PIM performance of the printed circuits is reported for the first time. The comprehensive measurement results, observations of the selfimprovement of the PIM performance and the effect of panel bending on PIM generation in printed boards with different finishing are presented. A consistent physical interpretation of the observed phenomena is proposed. The results of this study provide new important considerations for the design and characterisation of low-PIM printed circuits.

Electronic states and spin-forbidden cooling transitions of AlH and AlF

The feasibility of laser cooling AlH and AlF is investigated using ab initio quantum chemistry. All the electronic states corresponding to the ground and lowest two excited states of the Al atom are calculated using multi-reference configuration interaction (MRCI) and the large AV6Z basis set for AlH. The smaller AVQZ basis set is used to calculate the valence electronic states of AlF. Theoretical Franck-Condon factors are determined for the A(1)Pi -> X(1)Sigma(+) transitions in both radicals and found to agree with the highly diagonal factors found experimentally, suggesting computational chemistry is an effective method for screening suitable laser cooling candidates. AlH does not appear to have a transition quite as diagonal as that in SrF (which has been laser cooled) but the A(1)Pi -> X(1)Sigma(+) transition transition of AlF is a strong candidate for cooling with just a single laser, though the cooling frequency is deep in the UV. Furthermore, the a (3)Pi -> X(1)Sigma(+) transitions are also strongly diagonal and in AlF is a practical method for obtaining very low final temperatures around 3 mu K.

Job strain and adverse health behaviors: The Finnish public sector study

Objective: The objective of this study was to explore the association between job strain and the co-occurrence of adverse health behaviors, smoking; heavy drinking; obesity, and physical inactivity. Methods. The authors studied cross-sectional data of 34,058 female and 8154 male public sector employees. Results: Multinomial logistic regression models adjusted for sex, age, basic education, marital status, and type of job contract showed that high job strain and passive jobs were associated with 1.3 to 1.4 times higher odds of having >= 3 (vs 0) adverse health behaviors. Among men, low job control was associated with a 1.3 fold likelihood and amon women active jobs were associated with a 1.2 fold likelihood of having >= 3 (vs 0) adverse behaviors. High demands were associated with a higher likelihood of co-occurrence of one to two (vs 0) adverse behav irs among women. Conclusions. b strain conditions may be associated with the co-occurrence of adverse health behaviors that contribute to preventable chronic diseases. Clinical Significance. Adversejob conditions may increase the likelihood of co-occurring health risk behaviors. Reducing work stress by increasingl ob control and decreasing psychologic demands might help efforts to promote healthy 1 festyles.

Sperm DNA damage has a negative association with live birth rates after IVF.

Sperm DNA damage has a negative impact on pregnancy rates following assisted reproduction treatment (ART). The aim of the present study was to examine the relationship between sperm DNA fragmentation and live-birth rates after IVF and intracytoplasmic sperm injection (ICSI). The alkaline Comet assay was employed to measure sperm DNA fragmentation in native semen and in spermatozoa following density-gradient centrifugation in semen samples from 203 couples undergoing IVF and 136 couples undergoing ICSI. Men were divided into groups according to sperm DNA damage. Following IVF, couples with <25% sperm DNA fragmentation had a live-birth rate of 33%; in contrast, couples with >50% sperm DNA fragmentation had a much lower live-birth rate of 13%. Following ICSI, no significant differences in sperm DNA damage were found between any groups of patients. Sperm DNA damage was also associated with low live-birth rates following IVF in both men and couples with idiopathic infertility: 39% of couples and 41% of men with idiopathic infertility have high sperm DNA damage. Sperm DNA damage assessed by the Comet assay has a close inverse relationship with live-birth rates after IVF.

Sperm DNA damage has a negative impact on assisted reproduction treatment outcome, in particular, on pregnancy rates. The aim of the present study was to examine the relationship between sperm DNA fragmentation and live-birth rates after IVF and intracytoplasmic sperm injection (ICSI). The alkaline Comet assay was employed to measure sperm DNA fragmentation in native semen and in spermatozoa following density-gradient centrifugation in semen samples from 203 couples undergoing IVF and 136 couples undergoing ICSI. Men were divided into groups according to sperm DNA damage and treatment outcome. Following IVF, couples with <25% sperm DNA fragmentation had a live birth rate of 33%. In contrast, couples with >50% sperm DNA fragmentation had a much lower live-birth rate of 13% following IVF. Following ICSI, there were no significant differences in levels of sperm DNA damage between any groups of patients. Sperm DNA damage was also associated with the very low live-birth rates following IVF in both men and couples with idiopathic infertility: 39% of couples and 41% of men have high level of sperm DNA damage. Sperm DNA damage assessed by the Comet assay has a close inverse relationship with live-birth rates after IVF.

The United Kingdom Glaucoma Treatment Study:a multicenter, randomized, placebo-controlled clinical trial: design and methodology

Elevated intraocular pressure (IOP) is a major risk factor for the deterioration of open-angle glaucoma (OAG); medical IOP reduction is the standard treatment, yet no randomized placebo-controlled study of medical IOP reduction has been undertaken previously. The United Kingdom Glaucoma Treatment Study (UKGTS) tests the hypothesis that treatment with a topical prostaglandin analog, compared with placebo, reduces the frequency of visual field (VF) deterioration events in OAG patients by 50% over a 2-year period.

The Eschatology of Global Warming in a Scottish Fishing Village

In Gamrie, an Aberdeenshire fishing village home to 700 people and six millennialist Protestant churches, global warming is more than just a 'hoax': it is a demonic conspiracy that threatens to bring about the ruin of the entire human race. Such a certainty was rendered intelligible to local Christians by viewing it through the lens of dispensationalist theology brought to the village by the Plymouth Brethren. In a play on Weberian notions of disenchantment, I argue that whereas Gamrie's Christians rejected global warming as a false eschatology, and environmentalism as a false salvationist religion, supporters of the climate change agenda viewed global warming as an apocalyptic reality and environmentalism as providing salvific redemption. Both rhetorics – each engaged in a search for 'signs of the end times' – are thus millenarian.

Beyond the National Resource Privilege: towards an International Court of the Environment

The national resource privilege, which holds that states are allowed to control all the natural resources found in their territory, is a cornerstone of international politics. Supporters of the national resource privilege claim that without the privilege states would fail to be sovereign and self-determining entities which provide for the needs of their citizens. However, as this paper shows the case is not as simple as that. In fact, control over resources must be carefully unpacked. Doing so shows that states do not require full control over all resources found in their territory in order to be sovereign. Moreover, sovereignty and self-determination come with a set of responsibilities and duties attached. Based on these observations the paper will sketch the contours of an alternative resource governance scheme built around the idea of an International Court of the Environment.