XMM-Newton observations of the Galactic Centre Region - II: The soft thermal emission

We have extended our earlier study (Heard & Warwick 2013, Paper I) of the X-ray emission emanating from the central 100 pc x 100 pc region of our Galaxy to an investigation of several features prominent in the soft X-ray (2-4.5 keV) band. We focus on three specific structures: a putative bipolar outflow from the vicinity of Sgr A*; a high surface brightness region located roughly 12 arcmin to the north-east of Sgr A*; and a lower surface-brightness extended loop feature seen to the south of Sgr A*. We show that all three structures are thermal in nature and have similar temperatures (kT ~ 1 keV). The inferred X-ray luminosities lie in the range (2 - 10) x 10^34 erg s^-1. In the case of the bipolar feature we suggest that the hot plasma is produced by the shock-heating of the winds from massive stars within the Central Cluster, possibly collimated by the Circumnuclear Disc. Alternatively the outflow may be driven by outbursts on Sgr A*, which follow tidal disruption events occurring at a rate of roughly 1 every 4000 yr. The north-east enhancement is centred on a candidate PWN which has a relatively hard non-thermal X-ray spectrum. We suggest that the coincident soft-thermal emission traces the core of a new thermal-composite supernova remnant, designated as SNR G0.13-0.12. There is no clear evidence for an associated radio shell but such a feature may be masked by the bright emission of the nearby Radio Arc and other filamentary structures. SNR G0.13-0.12 is very likely interacting with the nearby molecular cloud, G0.11-0.11, and linked to the Fermi source, 2FGL J1746.4-2851c. Finally we explore a previous suggestion that the elliptically-shaped X-ray loop to the south of Sgr A*, of maximum extent ~45 pc, represents the shell of a superbubble located in the GC region. Although plausible, the interpretation of this feature in terms a coherent physical structure awaits confirmation.Comment: 17 pages, 6 figures, accepted for publication in MNRA

An algorithm for determining program feasibility of a multi-mode PAM commutator telemetry system Technical report no. 10

Algorithm formulation for evaluation of strapping arrangement programs for PAM multimode commutation system of Saturn telemetry syste

Fabrication and characterizations of proton-exchanged LiNbO3 waveguides fabricated by inductively coupled plasma technique

This Letter reports the use of an inductively coupled plasma technique for fabrication of proton-exchanged (PE) LiNbO3 (LN) waveguides. Planar and stripe waveguides have been formed in Y-cut LN which are difficult to obtain with the conventional molten acid method due to the occurrence of surface damage. Secondary ion mass spectrometry, scanning electron microscopy, and infrared absorption spectrum characterization results revealed that a uniform vertical PE profile with a single low order crystal phase has been directly obtained as a result of this unique process. X-ray photoelectron spectroscopy characterization of the treated surface revealed the existence of NbO as the cause for a sometimes darkened surface and confirms the ability to completely restore the surface to LN by oxygen plasma treatment. Atomic force microscopy measurement confirms that good surface quality has been maintained after regeneration of the surface to LN

Crystal structure of bis(μ2-di-n-butyldithiocarbamato-κ3S,S′:S;κ3S:S:S′)-hexacarbonyl-di-rhenium(I), C24H36N2O6Re2

C24H36N2O6Re2, triclinic, P¯1 (no. 2), a=10.3013(2) Å, b=11.3471(2) Å, c=14.5967(3) Å, α=72.540(2)°, β=73.074(2)°, γ=85.369(2)°, V =1557.05(6) Å3, Z =2, Rgt(F)=0.0214, wRref(F2)=0.0466, T =100(2) K

Case reports describing treatments in the emergency medicine literature: missing and misleading information

Abstract Background Although randomized trials and systematic reviews provide the "best evidence" for guiding medical practice, many emergency medicine journals still publish case reports (CRs). The quality of the reporting in these publications has not been assessed. Objectives In this study we sought to determine the proportion of treatment-related case reports that adequately reported information about the patient, disease, interventions, co-interventions, outcomes and other critical information. Methods We identified CRs published in 4 emergency medicine journals in 2000–2005 and categorized them according to their purpose (disease description, overdose or adverse drug reactioin, diagnostic test or treatment effect). Treatment-related CRs were reviewed for the presence or absence of 11 reporting elements. Results All told, 1,316 CRs were identified; of these, 85 (6.5%; 95CI = 66, 84) were about medical or surgical treatments. Most contained adequate descriptions of the patient (99%; 95CI = 95, 100), the stage and severity of the patient's disease (88%; 95CI = 79, 93), the intervention (80%; 95CI = 70, 87) and the outcomes of treatment (90%; 95CI = 82, 95). Fewer CRs reported the patient's co-morbidities (45%; 95CI = 35, 56), concurrent medications (30%; 95CI = 21, 40) or co-interventions (57%; 95CI = 46, 67) or mentioned any possible treatment side-effects (33%; 95CI = 24, 44). Only 37% (95CI = 19, 38) discussed alternative explanations for favorable outcomes. Generalizability of treatment effects to other patients was mentioned in only 29% (95CI = 20, 39). Just 2 CRs (2.3%; 95CI = 1, 8) reported a 'denominator" (number of patients subjected to the same intervention, whether or not successful. Conclusion Treatment-related CRs in emergency medicine journals often omit critical details about treatments, co-interventions, outcomes, generalizability, causality and denominators. As a result, the information may be misleading to providers, and the clinical applications may be detrimental to patient care.</p

Characterisation and improvement of j(O¹D) filter radiometers

Atmospheric O3 → O(1D) photolysis frequencies j(O1D) are crucial parameters for atmospheric photochemistry because of their importance for primary OH formation. Filter radiometers have been used for many years for in situ field measurements of j(O1D). Typically the relationship between the output of the instruments and j(O1D) is non-linear because of changes in the shape of the solar spectrum dependent on solar zenith angles and total ozone columns. These non-linearities can be compensated for by a correction method based on laboratory measurements of the spectral sensitivity of the filter radiometer and simulated solar actinic flux density spectra. Although this correction is routinely applied, the results of a previous field comparison study of several filter radiometers revealed that some corrections were inadequate. In this work the spectral characterisations of seven instruments were revised, and the correction procedures were updated and harmonised considering recent recommendations of absorption cross sections and quantum yields of the photolysis process O3 → O(1D). Previous inconsistencies were largely removed using these procedures. In addition, optical interference filters were replaced to improve the spectral properties of the instruments. Successive determinations of spectral sensitivities and field comparisons of the modified instruments with a spectroradiometer reference confirmed the improved performance. Overall, filter radiometers remain a low-maintenance alternative of spectroradiometers for accurate measurements of j(O1D) provided their spectral properties are known and potential drifts in sensitivities are monitored by regular calibrations with standard lamps or reference instruments

Hydrodinamic Aspects of a High-Speed SWATH and New Hull Form

The main problems of high-speed ships operating in open seas are their insufficient seaworthiness and speed loss in high sea states. Small Water-plane Area Twin-Hulls (SWATH) are characterised by excellent seaworthiness, but the hull forms of a traditional SWATH are not suited for higher speeds. A new shape of underwater gondola has been developed for a semi-planing (S/P) SWATH. Additionally, hydrofoils can be applied to this ship to provide the optimal dynamic draught and trim, to mitigate motions in rough seas, and even to carry a part of the ship weight. The relative speed of this SWATH can be beneficially increased up to the displacement Froude number 3. Several concept designs addressing naval and civil transportation needs are outlined in this paper

Previous reproductive history and post-natal family planning among HIV-infected women in Ukraine

BACKGROUND: Ukraine has the highest antenatal HIV prevalence in Europe. The national prevention of mother-to-child transmission (MTCT) programme has reduced the MTCT rate, but less attention has been given to the prevention of unintended pregnancy among HIV-positive women. Our objectives were to describe the reproductive health, condom use and family planning (FP) practices of HIV-positive childbearing Ukrainian women and to identify factors associated with different methods of post-natal contraception. METHODS: HIV-infected childbearing women, diagnosed before or during pregnancy, were enrolled prospectively in a post-natal cohort study in four regional HIV/AIDS centres in Ukraine from December 2007. Logistic regression models were used to identify factors associated with post-natal FP practices. RESULTS: Data were available for 371 women enrolled by March 2009; 82% (n = 303) were married or cohabiting, 27% (97 of 363) reported a current HIV-negative sexual partner and 69% were diagnosed with HIV during their most recent pregnancy. Overall, 21% (75 of 349) of women were not using contraception post-natally (of whom 80% reported no current sexual activity), 50% (174 of 349) used condoms, 20% (74 of 349) relied solely/partially on coitus interruptus and 4% used hormonal methods or intrauterine device. Among married/cohabiting women, consistent use of condoms in the previous pregnancy [AOR 1.96 (95%CI 1.06–3.62)], having an HIV-positive partner [AOR 0.42 (0.20–0.87)], current sexual activity [AOR 4.53 (1.19–17.3)] and study site were significantly associated with post-natal condom use; 16% of those with HIV-negative partners did not use condoms. Risk factors for non-use of FP were lack of affordability [AOR 6.34 (1.73–23.2)] and inconsistent use of condoms in the previous pregnancy [AOR 7.25 (1.41–37.2)]. CONCLUSIONS: More than 40% of HIV-positive women in this population are at risk of unintended pregnancy and the one in six women in HIV-discordant couples not using barrier methods risk transmitting HIV to their partners. Our study results are limited by the observational nature of the data and the potential for both measured and unmeasured confounding

Prioritisation of weed species relevant to Australian livestock industries for biological control

Classical biological control is the only realistic option for managing many of the most serious weeds affecting livestock industries in Australia. This project developed and applied a framework, based on a matrix assessment system, to prioritise biocontrol efforts using new agents against 79 weed taxa. These taxa were identified in a concurrent project as priorities for Research, Development and Extension to address weed problems of Australian livestock industries. The framework considered the current and potential impacts of the weeds versus prospects for biocontrol. The latter combined assessments of feasibility of undertaking a biocontrol program that would yield host-specific agents, and the likelihood that agents would be successful in mitigating the impacts of the weeds once released in Australia. Each categorisation was supported with a written rationale that explained the ranking assigned and captured uncertainties. Key investment areas for future actions to address biocontrol knowledge gaps for each weed were identified. Twenty-one weeds with the highest combined rankings for biocontrol prospects and current and/or potential impacts were shortlisted as priority taxa for future investment. Results provide the best available information for funding agencies responsible for RD&E for livestock industries to make investment decisions across their weed biocontrol portfolio

Dynamics of Generalized Assisted Inflation

We study the dynamics of multiple scalar fields and a barotropic fluid in an FLRW-universe. The scalar potential is a sum of exponentials. All critical points are constructed and these include scaling and de Sitter solutions. A stability analysis of the critical points is performed for generalized assisted inflation, which is an extension of assisted inflation where the fields mutually interact. Effects in generalized assisted inflation which differ from assisted inflation are emphasized. One such a difference is that an (inflationary) attractor can exist if some of the exponential terms in the potential are negative.Comment: 27 page