Measurements of mass and momentum flux in non-ideal molecular beams

Momentum transfer and mass determinations for nonideal molecular beam - fluid mechanic

Gas morphology and energetics at the surface of PDRs: New insights with Herschel observations of NGC 7023

Context. We investigate the physics and chemistry of the gas and dust in dense photon-dominated regions (PDRs), along with their dependence on the illuminating UV field. Aims. Using Herschel/HIFI observations, we study the gas energetics in NGC 7023 in relation to the morphology of this nebula. NGC 7023 is the prototype of a PDR illuminated by a B2V star and is one of the key targets of Herschel. Methods. Our approach consists in determining the energetics of the region by combining the information carried by the mid-IR spectrum (extinction by classical grains, emission from very small dust particles) with that of the main gas coolant lines. In this letter, we discuss more specifically the intensity and line profile of the 158 μm (1901 GHz) [C ii] line measured by HIFI and provide information on the emitting gas. Results. We show that both the [C ii] emission and the mid-IR emission from polycyclic aromatic hydrocarbons (PAHs) arise from the regions located in the transition zone between atomic and molecular gas. Using the Meudon PDR code and a simple transfer model, we find good agreement between the calculated and observed [C ii] intensities. Conclusions. HIFI observations of NGC 7023 provide the opportunity to constrain the energetics at the surface of PDRs. Future work will include analysis of the main coolant line [O i] and use of a new PDR model that includes PAH-related species

From cellular properties to population asymptotics in the Population Balance Equation

Proliferating cell populations at steady state growth often exhibit broad protein distributions with exponential tails. The sources of this variation and its universality are of much theoretical interest. Here we address the problem by asymptotic analysis of the Population Balance Equation. We show that the steady state distribution tail is determined by a combination of protein production and cell division and is insensitive to other model details. Under general conditions this tail is exponential with a dependence on parameters consistent with experiment. We discuss the conditions for this effect to be dominant over other sources of variation and the relation to experiments.Comment: Exact solution of Eq. 9 is adde

Comparing proxy rated quality of life of people living with dementia in care homes

Background: Improving quality of life (QOL) for people with dementia is a priority. In care homes, we often rely on proxy ratings from staff and family but we do not know if, or how, they differ in care homes. Methods: We compared 1056 pairs of staff and family DEMQOL-Proxy ratings from 86 care homes across England. We explored factors associated with ratings quantitatively using multilevel modelling and, qualitatively, through thematic analysis of 12 staff and 12 relative interviews. Results: Staff and family ratings were weakly correlated (ρs = 0.35). Median staff scores were higher than family's (104 v. 101; p < 0.001). Family were more likely than staff to rate resident QOL as ‘Poor’ (χ2 = 55.91, p < 0.001). Staff and family rated QOL higher when residents had fewer neuropsychiatric symptoms and severe dementia. Staff rated QOL higher in homes with lower staff:resident ratios and when staff were native English speakers. Family rated QOL higher when the resident had spent longer living in the care home and was a native English. Spouses rated residents’ QOL higher than other relatives. Qualitative results suggest differences arise because staff felt good care provided high QOL but families compared the present to the past. Family judgements centre on loss and are complicated by decisions about care home placement and their understandings of dementia. Conclusion: Proxy reports differ systematically between staff and family. Reports are influenced by the rater:staff and family may conceptualise QOL differently

A feasibility randomised controlled trial of the DECIDE intervention: dementia carers making informed decisions

YesFamily carers report high levels of decisional conflict when deciding whether their relative with dementia can continue to be cared for in their own home. We tested, in a feasibility randomised controlled trial, the first decision aid (the DECIDE manual) aiming to reduce such conflict. Twenty family carers received the DECIDE intervention, and 21 received usual treatment. The intervention group had reduced decisional conflict compared with controls (mean difference −11.96, 95% confidence interval −20.10 to −3.83, P=0.005). All carers receiving the intervention completed and valued it, despite some still reporting difficulties with family conflict and problems negotiating services. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license

Offside goals and induced breaches of contract

An analysis of Global Resources Group Ltd v Mackay which explores the possibility of building links between the offside goals rule and nominate delict of inducing breach of contract

The CHESS spectral survey of star forming regions: Peering into the protostellar shock L1157-B1 - II. Shock dynamics

Context. The outflow driven by the low-mass class 0 protostar L1157 is the prototype of the so-called chemically active outflows. The bright bowshock B1 in the southern outflow lobe is a privileged testbed of magneto-hydrodynamical (MHD) shock models, for which dynamical and chemical processes are strongly interdependent. Aims. We present the first results of the unbiased spectral survey of the L1157-B1 bowshock, obtained in the framework of the key program “Chemical HErschel Surveys of star forming regions” (CHESS). The main aim is to trace the warm and chemically enriched gas and to infer the excitation conditions in the shock region. Methods. The CO 5-4 and o-H2_O 1_(10)–1_(01) lines have been detected at high-spectral resolution in the unbiased spectral survey of the HIFI-band 1b spectral window (555–636 GHz), presented by Codella et al. in this volume. Complementary ground-based observations in the submm window help establish the origin of the emission detected in the main-beam of HIFI and the physical conditions in the shock. Results. Both lines exhibit broad wings, which extend to velocities much higher than reported up to now. We find that the molecular emission arises from two regions with distinct physical conditions : an extended, warm (100 K), dense (3 × 10^5 cm^(-3)) component at low-velocity, which dominates the water line flux in Band 1; a secondary component in a small region of B1 (a few arcsec) associated with high-velocity, hot (>400 K) gas of moderate density ((1.0–3.0) × 10^4 cm^(-3)), which appears to dominate the flux of the water line at 179μm observed with PACS. The water abundance is enhanced by two orders of magnitude between the low- and the high-velocity component, from 8 × 10^(-7) up to 8 × 10^(-5). The properties of the high-velocity component agree well with the predictions of steady-state C-shock models