Interactions between Sheets of Phonons in Liquid 4He

We have created two sheets of 1 K phonons in liquid 4He at 55 mK such that they intersect each other as they move towards a common point. If the two sheets have a small angle between them, they interact strongly and create a hot line in the liquid helium. This line is continuously fed with energy from the two sheets and loses energy by creating high-energy phonons. If the angle between the sheets is larger than 30 they do not interact but pass through each other. These results give direct evidence for the composition of the sheets: they comprise strongly interacting low-energy phonons which occupy a narrow cone in momentum space

Characterizing the i-band variability of YSOs over six orders of magnitude in time-scale

We present an i-band photometric study of over 800 young stellar objects in the OB association Cep OB3b, which samples time-scales from one minute to 10 yr. Using structure functions we show that on all time-scales (τ) there is a monotonic decrease in variability from Class I to Class II through the transition disc (TD) systems to Class III, i.e. the more evolved systems are less variable. The Class Is show an approximately power-law increase (τ0.8) in variability from time-scales of a few minutes to 10 yr. The Class II, TDs, and Class III systems show a qualitatively different behaviour with most showing a power-law increase in variability up to a time-scale corresponding to the rotational period of the star, with little additional variability beyond that time-scale. However, about a third of the Class IIs shows lower overall variability, but their variability is still increasing at 10 yr. This behaviour can be explained if all Class IIs have two primary components to their variability. The first is an underlying roughly power-law variability spectrum, which evidence from the infrared suggests is driven by accretion rate changes. The second component is approximately sinusoidal and results from the rotation of the star. We suggest that the systems with dominant longer time-scale variability have a smaller rotational modulation either because they are seen at low inclinations or have more complex magnetic field geometries. We derive a new way of calculating structure functions for large simulated data sets (the ‘fast structure function’), based on fast Fourier transforms

Perceptions of perinatal alcohol use and treatment needs in Cape Town, South Africa: a qualitative study

Background: South Africa has one of the world’s highest rates of foetal alcohol spectrum disorders (FASD). Recent evidence also showed that alcohol use during lactation significantly compromises child development in children exposed to alcohol through breastfeeding, independent of prenatal alcohol exposure. This study explored perceptions of perinatal alcohol use and treatment needs in Cape Town, South Africa, to inform the development of an intervention to encourage alcohol abstinence during pregnancy and breastfeeding. Methods: Individual in-depth interviews (IDIs) were conducted with women who were pregnant with a recent history of alcohol use (n=32) and clinic and community stakeholders (n=16). Interviews were audio recorded and transcribed verbatim. Coding and thematic analyses were conducted in NVivo 12. Results: Results indicate widespread perception that women know the dangers of drinking alcohol while pregnant with much less known about drinking while breastfeeding. Mixed views were shared about whether women who are pregnant or breastfeeding experience alcohol-related stigma. Participants described contextual factors impacting drinking that include interpersonal violence, lack of support, stress, anxiety and poverty, and drinking being normalised. Finally, participants had mixed views and conflicting knowledge of available resources to support alcohol reduction and highlighted a desire for support groups and the involvement of partners in alcohol interventions. Conclusions: Findings from this study highlight the need for an alcohol intervention programme that is innovative and tailored to the needs of women who are pregnant or postpartum. It also highlights the importance of including community-based support and partner involvement in these interventions

Kerbside recycling: a case study from the North-west of England

It is widely agreed that public support is vital to the success of most recycling schemes; the actions of householders are paramount to the success of sustainable waste policies. However, the success of recycling schemes is not just dependent on public participation; it is also dependent on careful planning, effective design and tailoring to local needs.This study has evaluated a kerbside recycling scheme in the north-west of England by comparing the recycling performance of those on alternate collections of residual waste and recyclates with those on weekly residual collections and fortnightly recyclate collections. Three data collection methodologies were adopted: postal questionnaires, set-out rate monitoring, and personal interviews with policy writers.The results demonstrated that alternate collections produce higher recycling set-out rates, suggesting that alternate collections will also generate higher recycling rates. The research showed that if designed and complemented by other services, then an alternate collection system is a realistic waste management approach. However, the local authority and the public appear to use different indicators of success for the scheme. The local authority uses governmental performance indicators (such as best value performance indicators—BVPIs) to measure success, whereas the public's indicators of success tend to focus more on issues such as required changes to established behaviours, convenience and personal preferences.A key recommendation from this study is that all local authorities should carry out local opinion surveys on an annual basis to supplement the BVPIs required by statute. This should help them to fill the information gaps in order to provide a comprehensive, up-to-date and user-responsive waste management service to the publi

Interactions between Sheets of Phonons in Liquid 4He

We have created two sheets of 1 K phonons in liquid 4He at 55 mK such that they intersect each other as they move towards a common point. If the two sheets have a small angle between them, they interact strongly and create a hot line in the liquid helium. This line is continuously fed with energy from the two sheets and loses energy by creating high-energy phonons. If the angle between the sheets is larger than 30 they do not interact but pass through each other. These results give direct evidence for the composition of the sheets: they comprise strongly interacting low-energy phonons which occupy a narrow cone in momentum space

Compliance with water legislation in waste management facilities: experiences from UK small and medium sized enterprises

This study investigated the legal compliance of SMEs with water legislation in UK waste management facilities. The research incorporated legislation controlling oil storage, ground water protection and discharges to sewers and surface waters. Compliance audits and SME management and site staff interviews were conducted utilising regulation-specific and environmental offences’ audit templates. A total of 20 SMEs from the north-west of England were audited between April-September 2008. The research indicates: -• Low levels of compliance with environmental permit conditions and water legislation; SMEs failed to comply with the ‘letter’ and ‘spirit’ of the law; • There is a link between compliance and environmental protection, although, it was unclear as to the extent of this link; and• SMEs considered compliance to be what the regulator identified rather than that detailed in legislation; further research is needed to identify the most efficient balance in regulator inspection frequenc

Некоторые особенности длинноимпульсного режима распространения фононного листа в сверхтекучем ⁴He

Исследовано угловое распределение плотности энергии анизотропного «фононного листа» при его распространении в сверхтекучем ⁴He при длительности импульса до 300 нс. Наличие плоского участка на угловых зависимостях фононного сигнала объясняется образованием «горячего» участка в центральной области листа и процессом генерации высокоэнергетических фононов в этом центральном участке. Насыщение ширины плоского участка при длительностях импульса вблизи 300 нс объясняется реализацией длинноимпульсного режима распространения пучка.Досліджено кутовий розподіл густини енергії анізотропного «фононного аркушу» при його поширенні в надплинному ⁴He при довжині імпульсу до 300 нс. Наявність плоскої ділянки на кутових залежностях фононного сигналу пояснюється утворенням «гарячої» ділянки в центральній області аркушу та процесом генерації високоенергетичних фононів в цій центральній ділянці. Насичення ширини плоскої ділянки при тривалості імпульсу поблизу 300 нс пояснюється реалізацією довгоімпульсного режиму поширення пучка.The angular distributing of energy density of “phonon sheet” at it propagation in superfluid ⁴He at length of impulse about 300 ns is investigated. The availability of flat top on angular dependences of phonon signal is explained by formation of «hot» area in the central region of sheet and process of creation of high energy phonons in this area. The saturation of the width of the flat top for impulse near-by 300 ns is explained by realization of the long pulse regime