Actively stabilized wavelength-insensitive carrier elimination from an electro-optically modulated laser beam

We demonstrate a simple and robust technique for removal of the carrier wave from a phase-modulated laser beam, using a noninterferometric method that is insensitive to the modulation frequency and instead exploits the polarization dependence of electro-optic modulation. An actively stabilized system using feedback via a liquid crystal cell yields long-term carrier suppression in excess of 28 dB at the expense of a 6.5 dB reduction in sideband power

Developing Interventions for Scaling Up UK Upcycling

open access articleUpcycling presents one of many opportunities for reducing consumption of materials and energy. Despite recent growth evidenced by increasing numbers of practitioners and businesses based on upcycling, it remains a niche activity and requires scaling up to realise its potential benefits. This paper investigates UK household upcycling in order to develop interventions for scaling up upcycling in the UK. Mixed methods were used in four stages: (a) Interviews to gain insights into UK upcycling; (b) a survey to discover key factors influencing UK upcycling; (c) intervention development based on the synthesis of interviews and survey; and (d) use of a semi-Delphi technique to evaluate and develop initial interventions. The results showed approaches to upcycling (e.g., wood, metal and fabric as frequently used materials, online platforms as frequently used source of materials), context for upcycling (e.g., predominant use of home for upcycling), factors influencing UK upcycling with key determinants (i.e., intention, attitude and subjective norm), important demographic characteristics considering a target audience for interventions (i.e., 30+ females) and prioritised interventions for scaling up (e.g., TV and inspirational media and community workshops as short-term high priority interventions). The paper further discusses implications of the study in terms of development of theory and practice of upcycling

The Return of the Beehives, Brylcreem and Botanical! An Historical Review of Hair Care Practices with a view to Opportunities for Sustainable Design

This paper considers hair care as a network of activities and routines which have consequences for environmental sustainability and which may be modified by design. It proposes that together with cultural knowledge, embodied skill and objects, these activities can be thought of as ‘practices’ that are reproduced and also change through time (Shove 2006). They consume resources and are therefore implicated in the issue of environmental sustainability. The paper draws on research into hair care practices conducted through in-depth interviews with female participants, as part of the first author’s PhD study. The discussion here however centres on historical work and Shove’s (2003) writing on bathing to explore the changing products and substances including ideas, technological and infrastructural aspects of cleansing and conditioning hair. Because these factors may determine when to wash or not to wash your hair they affect resource consumption. The paper concludes by outlining opportunities for sustainable design that follow from the insights gained by investigating the history of hair care in relation to the data collected during in-depth interviews. It highlights, as outlined by Hand et al (2005), that the resources consumed through hair care are influenced by the integrative nature of hair care as a practice rather than by individuals being dedicated to sustainability. To concentrate on single products without taking into account that hair care is practiced in everyday life is not likely to provide opportunities for sustainable living. What is considered ‘normal’ standards of hair care and means to achieve them needs to be conceptualised to identify opportunities to modify what is considered ‘normal’ through design. Keywords: Everyday Practices, Sustainable Design</p

The effect of rental rates on the extension of Conservation Reserve Program contracts

Given that the majority of conservation reserve program (CRP) contracts on approximately 36 million acres of enrolled land expire concurrently, re-enrollment decisions by farmers and the federal government have high budgetary implications. Using a survey of over 8,000 CRP contract holders, we apply an ordered response discrete choice model to explicitly model the range in rental rates over which the representative farmer may be ambivalent to renewing the CRP contract. Given the empirical results from the ordered response model, we estimate acreage re-enrollment as a function of the rental rate and compare them to results of a binomial choice model.CRP contracts; ordered probit; re-enrollment; respondent indifference

A nucleotide resolution map of Top2-linked DNA breaks in the yeast and human genome

DNA topoisomerases are required to resolve DNA topological stress. Despite this essential role, abortive topoisomerase activity generates aberrant protein-linked DNA breaks, jeopardising genome stability. Here, to understand the genomic distribution and mechanisms underpinning topoisomerase-induced DNA breaks, we map Top2 DNA cleavage with strand-specific nucleotide resolution across the S. cerevisiae and human genomes—and use the meiotic Spo11 protein to validate the broad applicability of this method to explore the role of diverse topoisomerase family members. Our data characterises Mre11-dependent repair in yeast and defines two strikingly different fractions of Top2 activity in humans: tightly localised CTCF-proximal, and broadly distributed transcription-proximal, the latter correlated with gene length and expression. Moreover, single nucleotide accuracy reveals the influence primary DNA sequence has upon Top2 cleavage—distinguishing sites likely to form canonical DNA double-strand breaks (DSBs) from those predisposed to form strand-biased DNA single-strand breaks (SSBs) induced by etoposide (VP16) in vivo

Meiotic DSB patterning: A multifaceted process

Meiosis is a specialized two-step cell division responsible for genome haploidization and the generation of genetic diversity during gametogenesis. An integral and distinctive feature of the meiotic program is the evolutionarily conserved initiation of homologous recombination (HR) by the developmentally programmed induction of DNA double-strand breaks (DSBs). The inherently dangerous but essential act of DSB formation is subject to multiple forms of stringent and self-corrective regulation that collectively ensure fruitful and appropriate levels of genetic exchange without risk to cellular survival. Within this article we focus upon an emerging element of this control—spatial regulation—detailing recent advances made in understanding how DSBs are evenly distributed across the genome, and present a unified view of the underlying patterning mechanisms employed

Chemostratigraphy of Upper Carboniferous (Pennsylvanian) sequences from the Southern North Sea (United Kingdom)

Important gas reservoirs occur in the Upper Carboniferous coal measures and red beds of the Southern North Sea. The thick red beds of the Boulton and Ketch formations are difficult to correlate, due to poor internal seismic definition, repetitive e-log signatures, and their barren nature. Although the underlying coal measures of the Westoe, Cleaver, and Caister Formations have better seismic resolution and contain palynomorphs, coals that die out laterally and the lack of diagnostic taxa over certain intervals contribute to their correlation being problematical. However, the application of chemostratigraphy to more than sixty wells from numerous fields in UK Quadrants 44 and 49, as well as from Dutch sector Blocks E, F, and K, allows the establishment of an independent, robust, detailed correlation framework for the aforesaid red beds and coal measures. Presented in this paper are correlative chemostratigraphic reference sections for the Caister, Westoe, Cleaver, Ketch, Boulton, and Step Graben formations. The chemostratigraphic zonations erected for these formations are based on variations in silty claystone geochemistry that can be tied to changes in provenance, climate, and depositional environment. In addition, the zonations are supported by stratigraphic changes in sandstone and coal geochemistry, the geochemical correlation of tonsteins and marine bands, and the recognition of different types of paleosol in the above formations. The chemostratigraphic correlation framework enables specific broad intervals ("packages") to be correlated between fields and is also used to constrain seismic correlations with a view to highlighting potential exploration targets. Furthermore, the same framework allows much thinner intervals ("units" and "subunits") to be correlated within fields: these smaller-scale correlations enhance reservoir correlations with respect to the development of fields such as Boulton, Schooner, Tyne, Ketch, and Topaz. In addition to using inorganic geochemical data to characterize and correlate sedimentological packages, data can also used to identify and correlate marker horizons and surfaces (tonsteins, coals, marine bands, major paleosols), which may be highly correlative low-diachrony surfaces, which greatly enhance the overall validity of the stratigraphic correlation scheme

Changes in the rate of nicotine metabolism across pregnancy: a longitudinal study

Aims: Increased nicotine metabolism during pregnancy could explain why nicotine replacement therapy (NRT) appears to be less effective on smoking cessation in pregnancy than in non-pregnant smokers, but little is known about nicotine metabolism across pregnancy. This study was conducted to determine when changes in nicotine metabolism occur during pregnancy and to describe the magnitude of these changes. Design: Longitudinal cohort study of pregnant smokers' nicotine metabolite ratio (NMR). Setting and Participants: 101 pregnant smokers recruited from hospital antenatal clinics in Nottingham, UK were asked to provide saliva samples at 8–14 weeks (n = 98), 18–22 weeks (n = 65), 32–36 weeks gestation (n = 47), 4 weeks postpartum (n = 44) and 12 weeks postpartum (n = 47). Measurements: Nicotine metabolite ratio (NMR) was measured using the ratio of cotinine to its primary metabolite trans-3'-hydroxycotinine. Multi-level modelling was used to detect any overall difference in NMR between time points. The 12 week postpartum NMR was compared with the NMRs collected antenatally and 4 weeks postpartum. Findings: NMR changed over time (p = 0.0006). Compared with NMR at 12 weeks postpartum, NMR was significantly higher at 18–22 weeks (26% higher, 95% CI 12% to 38%) and 32–36 weeks (23% higher, 95% CI 9% to 35%). There was no significant difference between the 8-14 weeks gestation or 4 weeks postpartum NMR and 12 weeks postpartum. Conclusions: Nicotine metabolism appears to be faster during pregnancy; this faster metabolism is apparent from 18 to 22 weeks of pregnancy and appears to fall by 4 weeks after childbirth

"The biggest gang"? Police and people in the 2011 England riots

Conflict with the police is a staple of civil disorder and the English riots of 2011 were no exception. The antagonism towards the police expressed by the rioters varied in intensity – from a low-level anger stemming from occasional negative experiences on the one hand to outright, visceral hostility on the other – but was visible everywhere riots took place. Leading politicians dismissed this hostility as nothing more than the typical wariness criminals have of the police. Indeed, it is undoubtedly the case that the police are an easy target for rioters seeking to explain away their conduct. Nevertheless, drawing on 270 interviews with people involved in the riots this paper shows that for some involved the police were a very deliberate and specific focus of anger and resentment. The basis of such feelings was complex and variable, but included historically poor relations between the police and particular communities, an inherited distrust of the police as an institution, to more particular and immediate experiences of mistreatment and prejudice – often coalescing around the perceived misuse of police powers such as stop and search

A new population of recently quenched elliptical galaxies in the SDSS

We use the Sloan Digital Sky Survey to investigate the properties of massive elliptical galaxies in the local Universe (z\leq0.08) that have unusually blue optical colors. Through careful inspection, we distinguish elliptical from non-elliptical morphologies among a large sample of similarly blue galaxies with high central light concentrations (c_r\geq2.6). These blue ellipticals comprise 3.7 per cent of all c_r\geq2.6 galaxies with stellar masses between 10^10 and 10^11 h^{-2} {\rm M}_{\sun}. Using published fiber spectra diagnostics, we identify a unique subset of 172 non-star-forming ellipticals with distinctly blue urz colors and young (< 3 Gyr) light-weighted stellar ages. These recently quenched ellipticals (RQEs) have a number density of 2.7-4.7\times 10^{-5}\,h^3\,{\rm Mpc}^{-3} and sufficient numbers above 2.5\times10^{10} h^{-2} {\rm M}_{\sun} to account for more than half of the expected quiescent growth at late cosmic time assuming this phase lasts 0.5 Gyr. RQEs have properties that are consistent with a recent merger origin (i.e., they are strong `first-generation' elliptical candidates), yet few involved a starburst strong enough to produce an E+A signature. The preferred environment of RQEs (90 per cent reside at the centers of < 3\times 10^{12}\,h^{-1}{\rm M}_{\sun} groups) agrees well with the `small group scale' predicted for maximally efficient spiral merging onto their halo center and rules out satellite-specific quenching processes. The high incidence of Seyfert and LINER activity in RQEs and their plausible descendents may heat the atmospheres of small host halos sufficiently to maintain quenching.Comment: 26 pages, 9 figures. Revised version; accepted for publication in MNRA