ORFEUS-II Far-Ultraviolet Observations of 3C273: 1. Interstellar and Intergalactic Absorption Lines

We present the first intermediate-resolution (lambda / 3000) spectrum of the bright quasi-stellar object 3C273 at wavelengths between 900 and 1200 A. Observations were performed with the Berkeley spectrograph aboard the ORFEUS-SPAS II mission. We detect Lyman beta counterparts to previously-identified intergalactic Lyman-alpha features at cz = 19900, 1600, and 1000 km/s; counterparts to other putative Lyman-alpha clouds along the sight line are below our detection limit. The strengths of the two very low redshift Lyman-beta features, which are believed to arise in Virgo intracluster gas, exceed preflight expectations, suggesting that the previous determination of the cloud parameters may underestimate the true column densities. A curve-of-growth analysis sets a minimum H I column density of 4 E14/cm^2 for the 1600 km/s cloud. We find marginally significant evidence for Galactic H_2 along the sight line, with a total column density of about 1 E15/cm^2. We detect the stronger interstellar O VI doublet member unambiguously; the weaker member is blended with other features. If the Doppler b value for O VI is comparable to that determined for N V then the O VI column density is 7 +/- 2 E14/cm^2, significantly above the only previous estimate. The O VI / N V ratio is about 10, consistent with the low end of the range observed in the disk. Additional interstellar species detected for the first time toward 3C273 (at modest statistical significance) include P II, Fe III, Ar I, and S III.Comment: LaTeX file, 11 pages, 4 encapsulated PostScript figures. Uses aaspp4.sty and astrobib.sty. (Astrobib is available from http://www.stsci.edu/software/TeX.html .) The ORFEUS telescope is described at http://sag-www.ssl.berkeley.edu/orfeus/ . To appear in ApJ (Letters

A global analysis of genetic interactions in Caenorhabditis elegans

Abstract Background Understanding gene function and genetic relationships is fundamental to our efforts to better understand biological systems. Previous studies systematically describing genetic interactions on a global scale have either focused on core biological processes in protozoans or surveyed catastrophic interactions in metazoans. Here, we describe a reliable high-throughput approach capable of revealing both weak and strong genetic interactions in the nematode Caenorhabditis elegans. Results We investigated interactions between 11 'query' mutants in conserved signal transduction pathways and hundreds of 'target' genes compromised by RNA interference (RNAi). Mutant-RNAi combinations that grew more slowly than controls were identified, and genetic interactions inferred through an unbiased global analysis of the interaction matrix. A network of 1,246 interactions was uncovered, establishing the largest metazoan genetic-interaction network to date. We refer to this approach as systematic genetic interaction analysis (SGI). To investigate how genetic interactions connect genes on a global scale, we superimposed the SGI network on existing networks of physical, genetic, phenotypic and coexpression interactions. We identified 56 putative functional modules within the superimposed network, one of which regulates fat accumulation and is coordinated by interactions with bar-1(ga80), which encodes a homolog of β-catenin. We also discovered that SGI interactions link distinct subnetworks on a global scale. Finally, we showed that the properties of genetic networks are conserved between C. elegans and Saccharomyces cerevisiae, but that the connectivity of interactions within the current networks is not. Conclusions Synthetic genetic interactions may reveal redundancy among functional modules on a global scale, which is a previously unappreciated level of organization within metazoan systems. Although the buffering between functional modules may differ between species, studying these differences may provide insight into the evolution of divergent form and function

Extremely high He isotope ratios in MORB-source mantle from the proto-Iceland plume

The high <sup>3</sup>He/<sup>4</sup>He ratio of volcanic rocks thought to be derived from mantle plumes is taken as evidence for the existence of a mantle reservoir that has remained largely undegassed since the Earth's accretion. The helium isotope composition of this reservoir places constraints on the origin of volatiles within the Earth and on the evolution and structure of the Earth's mantle. Here we show that olivine phenocrysts in picritic basalts presumably derived from the proto-Iceland plume at Baffin Island, Canada, have the highest magmatic <sup>3</sup>He/<sup>4</sup>He ratios yet recorded. A strong correlation between <sup>3</sup>He/<sup>4</sup>He and <sup>87</sup>Sr/<sup>86</sup>Sr, <sup>143</sup>Nd/<sup>144</sup>Nd and trace element ratios demonstrate that the <sup>3</sup>He-rich end-member is present in basalts that are derived from large-volume melts of depleted upper-mantle rocks. This reservoir is consistent with the recharging of depleted upper-mantle rocks by small volumes of primordial volatile-rich lower-mantle material at a thermal boundary layer between convectively isolated reservoirs. The highest <sup>3</sup>He/<sup>4</sup>He basalts from Hawaii and Iceland plot on the observed mixing trend. This indicates that a <sup>3</sup>He-recharged depleted mantle (HRDM) reservoir may be the principal source of high <sup>3</sup>He/<sup>4</sup>He in mantle plumes, and may explain why the helium concentration of the 'plume' component in ocean island basalts is lower than that predicted for a two-layer, steady-state model of mantle structure

An update on vector boson pair production at hadron colliders

We present numerical results (including full one-loop QCD corrections) for the processes p p-bar and pp -> W+ W-, W+/- Z/gamma* and Z/gamma* Z/gamma* followed by the decay of the massive vector bosons into leptons. In addition to their intrinsic importance as tests of the standard model, these processes are also backgrounds to conjectured non-standard model processes. Because of the small cross sections at the Tevatron, full experimental control of these backgrounds will be hard to achieve. This accentuates the need for up-to-date theoretical information. A comparison is made with earlier work and cross section results are presented for p p-bar collisions at sqrt{s}=2 TeV and pp collisions at sqrt{s}=14 TeV. Practical examples of the use of our calculations are presented.Comment: 18 pages, 5 embedded figures, included extra reference [7

Ambulance-delivered transdermal glyceryl trinitrate versus sham for ultra-acute stroke: rationale, design and protocol for the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2 (RIGHT-2) trial (ISRCTN26986053)

Rationale: Vascular nitric oxide levels are low in acute stroke and donors such as glyceryl trinitrate have shown promise when administered very early after stroke. Potential mechanisms of action include augmentation of cerebral reperfusion, thrombolysis and thrombectomy, lowering blood pressure, and cytoprotection. Aim: To test the safety and efficacy of four days of transdermal glyceryl trinitrate (5 mg/day) versus sham in patients with ultra-acute presumed stroke who are recruited by paramedics prior to hospital presentation. Sample size estimates: The sample size of 850 patients will allow a shift in the modified Rankin Scale with odds ratio 0.70 (glyceryl trinitrate versus sham, ordinal logistic regression) to be detected with 90% power at 5% significance (two-sided). Design: The Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2 (RIGHT-2) is a multicentre UK prospective randomized sham-controlled outcome-blinded parallel-group trial in 850 patients with ultra-acute (4 h of onset) FAST-positive presumed stroke and systolic blood pressure 120 mmHg who present to the ambulance service following a 999 emergency call. Data collection is performed via a secure internet site with real-time data validation. Study outcomes: The primary outcome is the modified Rankin Scale measured centrally by telephone at 90 days and masked to treatment. Secondary outcomes include: blood pressure, impairment, recurrence, dysphagia, neuroimaging markers of the acute lesion including vessel patency, discharge disposition, length of stay, death, cognition, quality of life, and mood. Neuroimaging and serious adverse events are adjudicated blinded to treatment. Discussion: RIGHT-2 has recruited more than 500 participants from seven UK ambulance services. Status: Trial is ongoing. Funding: British Heart Foundation. Registration: ISRCTN26986053

Increased SBPase activity improves photosynthesis and grain yield in wheat grown in greenhouse conditions

To meet the growing demand for food, substantial improvements in yields are needed. This is particularly the case for wheat, where global yield has stagnated in recent years. Increasing photosynthesis has been identified as a primary target to achieve yield improvements. To increase leaf photosynthesis in wheat, the level of the Calvin-Benson cycle enzyme sedoheptulose-1,7-biphosphatase (SBPase) has been increased through transformation and expression of a Brachypodium dystachion SBPase gene construct. Transgenic lines with increased SBPase protein levels and activity were grown under greenhouse conditions and showed enhanced leaf photosynthesis and increased total biomass and dry seed yield. This showed the potential of improving yield potential by increasing leaf photosynthesis in a crop species such as wheat. The results are discussed with regards to future strategies for further improvement of photosynthesis in wheat.publishersversionPeer reviewe

Effectiveness of a training-of-trainers model in a HIV counseling and testing program in the Caribbean Region

<p>Abstract</p> <p>Objectives</p> <p>To evaluate the effectiveness and sustainability of a voluntary counseling and testing (VCT) training program based on a training-of-trainers (TOT) model in the Caribbean Region, we gathered data on the percentage of participants trained as VCT providers who were providing VCT services, and those trained as VCT trainers who were conducting VCT training.</p> <p>Methods</p> <p>The VCT training program trained 3,489 providers in VCT clinical skills and 167 in VCT training skills within a defined timeframe. An information-monitoring system tracked HIV trainings conducted, along with information about course participants and trainers. Drawing from this database, a telephone survey followed up on program-trained VCT providers; an external evaluation analyzed data on VCT trainers.</p> <p>Results</p> <p>Almost 65% of trained VCT providers could be confirmed as currently providing VCT services. This percentage did not decrease significantly with time. Of the VCT trainers, 80% became certified as trainers by teaching at least one course; of these, 66% taught more than one course.</p> <p>Conclusion</p> <p>A TOT-based training program is an effective and sustainable method for rapid scale-up of VCT services and training capacity in a large-scale VCT program.</p

Anastrozole (‘Arimidex’) blocks oestrogen synthesis both peripherally and within the breast in postmenopausal women with large operable breast cancer

The effect of anastrozole on peripheral and tumour aromatase activity and oestrogen levels in postmenopausal patients with oestrogen receptor-rich breast tumours was investigated. Twenty-six patients were randomly allocated to treatment with anastrozole 1 mg (n=13) or 10 mg (n=13), once daily. Before and after 12 weeks' treatment, patients were infused with 3H-Δ4 androstenedione (20 MBq) and 14C-oestrone (E1) (1 MBq) for 18 h. Oestrogens were purified from excised tumours and plasma samples taken after each infusion. Peripheral and tumour aromatase activity and tumour E1 uptake were calculated from levels of 3H and 14C in purified E1 fractions from tumour and plasma. Endogenous tumour oestrogens were measured by radioimmunoassay. Twenty-three patients were available for analysis (1 mg group, n=12; 10 mg group, n=11). Following treatment, anastrozole (1 and 10 mg) markedly inhibited peripheral aromatase in all patients (the difference between pre- and on-treatment values being highly significant P<0.0001). In situ aromatase activity was also profoundly decreased by anastrozole treatment in 16 of 19 tumours (the difference with treatment also being highly significant P=0.0009). Most tumours were able to concentrate E1 beyond levels in the circulation; anastrozole treatment had no consistent effect on uptake of E1. Endogenous tumour levels of both E1 and oestradiol (E2) were significantly reduced with therapy (P=0.028 for E1 and P=0.0019 for E2). Anastrozole (1 and 10 mg daily) effectively suppresses aromatase activity, and subsequently oestrogen levels, within the breast tissue of postmenopausal women with large or locally advanced, operable, oestrogen receptor-rich breast cancers

Robotic milking technologies and renegotiating situated ethical relationships on UK dairy farms

Robotic or automatic milking systems (AMS) are novel technologies that take over the labor of dairy farming and reduce the need for human-animal interactions. Because robotic milking involves the replacement of 'conventional' twice-a-day milking managed by people with a system that supposedly allows cows the freedom to be milked automatically whenever they choose, some claim robotic milking has health and welfare benefits for cows, increases productivity, and has lifestyle advantages for dairy farmers. This paper examines how established ethical relations on dairy farms are unsettled by the intervention of a radically different technology such as AMS. The renegotiation of ethical relationships is thus an important dimension of how the actors involved are re-assembled around a new technology. The paper draws on in-depth research on UK dairy farms comparing those using conventional milking technologies with those using AMS. We explore the situated ethical relations that are negotiated in practice, focusing on the contingent and complex nature of human-animal-technology interactions. We show that ethical relations are situated and emergent, and that as the identities, roles, and subjectivities of humans and animals are unsettled through the intervention of a new technology, the ethical relations also shift. © 2013 Springer Science+Business Media Dordrecht