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Household waste management practices in Charnwood borough, England
Household waste recycling rates vary between 20-60% across the UK. Legislative and financial measures introduced to reduce landfill disposal of waste in the UK, have impacted on the way Local Authorities operate their household waste and recycling collection services. This paper reports on the performance of Charnwood Borough Council (CBC), a Local Authority in England, it is responsible for the collection and recycling of waste from 67,000 households. This service is carried out by a private company, Serco, who operate household waste collections for 15 UK Local Authorities. To improve recycling performance CBC has changed the collection frequency and increased the number of materials segregated from residual waste for recovery. There have also been actions and campaigns to raise public awareness. Together these have improved recycling and composting rates in the CBC area from 16% in 2002/03 to 46.1% in 2010/11. This paper is a case study and progress report on the details of how this was achieved. It compares performance with other Local Authorities, explores the impact of local operational and policy issues on the amount of household waste collected for recycling. The research has concluded that differences in how the household waste services were provided and local policies influenced the amount of recyclates recovered. Local decision making and the ability to tailor services to suit different demographic areas, together with partnerships between neighbouring Authorities supported better sustainable waste management
New objects in old structures: The Iron Age hoard of the Palacio III megalithic funerary complex (Almadén de la Plata, Seville, Spain)
Cultural contact, exchange and interaction feature high in the list of challenging topics of current research on European Prehistory. Not far off is the issue of the changing role of monuments in the making and maintaining of key cultural devices such as memory and identity. Addressing both these highly-debated issues from a science-based perspective, in this paper we look at an unusual case study set in southern Iberia and illustrate how these archaeological questions can benefit from robust materials-science approaches.We present the contextual, morphological and analytical study of an exceptional Early Iron Age hoard composed of a number of different (and mostly exotic) materials such as amber, quartz, silver and ceramic. This hoard, found under the fallen orthostat of a megalithic structure built at least 2000 years earlier, throws new light on long-distance exchange networks and the effect they could have had on the cultural identities and social relations of local Iberian Early Iron Age communities. Moreover, the archaeometric study reveals how diverse and distant the sources of these item are (Northern Europe to Eastern and Western Mediterranean raw materials, as well as local and eastern technologies), therefore raising questions concerning the social mechanisms used to establish change and resistance in contexts of colonial encounter
On fatigue life prediction of Al-alloy 2024 plates in riveted joints
The purpose of this paper is to numerically investigate the fatigue life and the fatigue crack growth path of 2024 aluminum plate riveted joints. For this purpose, according to field observations, the parameters affecting fatigue life are obtained. Relevant geometric parameters such as rivet shank length, hole diameter and dimensional tolerances, as well as the location pattern of the rivets and the material of the rivet joints are studied. In this study, modeling is performed to calculate the equivalent plastic strain using the finite element method. For this purpose, a three-dimensional elastoplastic model is used for simulation. The information obtained from the finite element method in this study made it possible to place the rivets in this type of joint for use in high safety structures such as the aerospace industry. Given the importance of the problem of crack growth in 2024 aluminum plates, having the geometrical and physical parameters of the problem, the goal is to achieve the exact path of crack growth and fatigue life of riveted joints. Fatigue crack growth simulation is performed on the samples using the boundary element method. The stress intensity factor for different loading modes is determined using the boundary element method. The results showed that the geometric parameters and the rivet material have a significant effect on fatigue cracking in aluminum plates
The influence of perfusion solution on renal graft viability assessment
BACKGROUND: Kidneys from donors after cardiac or circulatory death are exposed to extended periods of both warm ischemia and intra-arterial cooling before organ recovery. Marshall’s hypertonic citrate (HOC) and Bretschneider’s histidine-tryptophan-ketoglutarate (HTK) preservation solutions are cheap, low viscosity preservation solutions used clinically for organ flushing. The aim of the present study was to evaluate the effects of these two solutions both on parameters used in clinical practice to assess organ viability prior to transplantation and histological evidence of ischemic injury after reperfusion. METHODS: Rodent kidneys were exposed to post-mortem warm ischemia, extended intra-arterial cooling (IAC) (up to 2 h) with preservation solution and reperfusion with either Krebs-Hensleit or whole blood in a transplant model. Control kidneys were either reperfused directly after retrieval or stored in 0.9% saline. Biochemical, immunological and histological parameters were assessed using glutathione-S-transferase (GST) enzymatic assays, polymerase chain reaction and mitochondrial electron microscopy respectively. Vascular function was assessed by supplementing the Krebs-Hensleit perfusion solution with phenylephrine to stimulate smooth muscle contraction followed by acetylcholine to trigger endothelial dependent relaxation. RESULTS: When compared with kidneys reperfused directly post mortem, 2 h of IAC significantly reduced smooth muscle contractile function, endothelial function and upregulated vascular cellular adhesion molecule type 1 (VCAM-1) independent of the preservation solution. However, GST release, vascular resistance, weight gain and histological mitochondrial injury were dependent on the preservation solution used. CONCLUSIONS: We conclude that initial machine perfusion viability tests, including ischemic vascular resistance and GST, are dependent on the perfusion solution used during in situ cooling. HTK-perfused kidneys will be heavier, have higher GST readings and yet reduced mitochondrial ischemic injury when compared with HOC-perfused kidneys. Clinicians should be aware of this when deciding which kidneys to transplant or discard
d-wave pairing symmetry in cuprate superconductors
Phase-sensitive tests of pairing symmetry have provided strong evidence for
predominantly d-wave pairing symmetry in both hole- and electron-doped high-Tc
cuprate superconductors. Temperature dependent measurements in YBCO indicate
that the d-wave pairing dominates, with little if any imaginary component, at
all temperatures from 0.5K through Tc. In this article we review some of this
evidence and discuss the implications of the universal d-wave pairing symmetry
in the cuprates.Comment: 4 pages, M2S 2000 conference proceeding
Effect of Iodine Doping on BiSrCaCuO: Charge Transfer or Interlayer Coupling?
A comparative study has been made of iodine-intercalated
BiSrCaCuO single crystal and 1 atm O
annealed BiSrCaCuO single crystal using AC
susceptibility measurement, X-ray photoemission (XPS) and angle-resolved
ultraviolet photoemission spectroscopy (ARUPS). AC susceptibility measurement
indicates that O-doped samples studied have T of 84 K,
whereas T of Iodine-doped samples studied are 80 K. XPS Cu 2p core
level data establish that the hole concentration in the CuO planes are
essentially the same for these two kinds of samples. ARUPS measurements show
that electronic structure of the normal states near the Fermi level has been
strongly affected by iodine intercalation. We conclude that the dominant effect
of iodine doping is to alter the interlayer coupling.Comment: LBL 9 pages, APS_Revtex. 5 Figures, available upon request.
UW-Madison preprin
The prevalence of intrusive memories in adult depression: A meta-analysis
Background Intrusive memories have typically been associated with post-traumatic stress disorder (PTSD) but some studies have suggested they can also occur in depression-alone. Objective This meta-analysis aimed to estimate the prevalence of intrusive memories in adult depression and to explore methodological and other factors that may moderate this prevalence. Method The databases PsycINFO, PsycARTICLES, MedLine, PubMed, CINAHL and Embase were searched for relevant articles, published up to and including July 2016. Studies measuring point prevalence of intrusive memories in adults aged 18 years or above with depression were included and assessed for quality. Meta-analysis was completed under a random effects model. Results Seven studies measuring point prevalence of intrusive memories in adult depression were included. The overall pooled prevalence estimate calculated was 76.0% (95% CI 59.4 – 89.4%), reducing to 66.0% (95% CI 51.0 – 79.5%) when restricted to intrusive memories experienced within the week prior to assessment. Heterogeneity was high. Between-groups analyses indicated that adults with depression are as likely to experience intrusive memories as adults with PTSD, and more likely to experience intrusive memories than healthy controls (risk ratio of 2.94, 95% CI 1.53 – 5.67). Limitations The strength of conclusions is limited by the small number of studies included. Consideration of the relationship between depression, intrusive memories and trauma exposure is required. Conclusions Intrusive memories are experienced by a large majority of adults with depression and may therefore be an important target for cognitive intervention. Larger scale measurement of clinical outcome is needed with identification of individual factors predicting treatment response
Ab-initio Quantum Enhanced Optical Phase Estimation Using Real-time Feedback Control
Optical phase estimation is a vital measurement primitive that is used to
perform accurate measurements of various physical quantities like length,
velocity and displacements. The precision of such measurements can be largely
enhanced by the use of entangled or squeezed states of light as demonstrated in
a variety of different optical systems. Most of these accounts however deal
with the measurement of a very small shift of an already known phase, which is
in stark contrast to ab-initio phase estimation where the initial phase is
unknown. Here we report on the realization of a quantum enhanced and fully
deterministic phase estimation protocol based on real-time feedback control.
Using robust squeezed states of light combined with a real-time Bayesian
estimation feedback algorithm, we demonstrate deterministic phase estimation
with a precision beyond the quantum shot noise limit. The demonstrated protocol
opens up new opportunities for quantum microscopy, quantum metrology and
quantum information processing.Comment: 5 figure
Analysis of the functional repertoire of a mutant form of survivin, K129E, which has been linked to lung cancer
Background
Survivin is a protein that is normally present only in G2 and M-phases in somatic cells, however, in cancer cells, it is expressed throughout the cell cycle. A prosurvival factor, survivin is both an inhibitor of apoptosis and an essential mitotic protein, thus it has attracted much attention as a target for new oncotherapies. Despite its prevalence in cancer, reports of survivin mutations have mostly been restricted to loci within its promoter, which increase the abundance of the protein. To date the only published mutation within the coding sequence is an adenine > guanine substitution in exon 4. This polymorphism, which was found in a cohort of Korean lung cancer patients, causes a lysine > glutamic acid mutation (K129E) in the protein. However, whether it plays a causative role in cancer has not been addressed.
Methods
Using site directed mutagenesis we recapitulate K129E expression in cultured human cells and assess its anti-apoptotic and mitotic activities.
Results
K129E retains its anti-apoptotic activity, but causes errors in mitosis and cytokinesis, which may be linked to its reduced affinity for borealin.
Conclusion
K129E expression can induce genomic instability by introducing mitotic aberrations, thus it may play a causative role in cancer
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