12,628 research outputs found
Ground state fidelity in bond-alternative Ising chains with Dzyaloshinskii-Moriya interactions
A systematic analysis is performed for quantum phase transitions in a
bond-alternative one-dimensional Ising model with a Dzyaloshinskii-Moriya (DM)
interaction by using the fidelity of ground state wave functions based on the
infinite matrix product states algorithm. For an antiferromagnetic phase, the
fidelity per lattice site exhibits a bifurcation, which shows spontaneous
symmetry breaking in the system. A critical DM interaction is inversely
proportional to an alternating exchange coupling strength for a quantum phase
transition. Further, a finite-entanglement scaling of von Neumann entropy with
respect to truncation dimensions gives a central charge c = 0.5 at the critical
point.Comment: 6 pages, 4 figure
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On Visible Homelessness and the Micro-Aesthetics of Public Space
In this article, we investigate the circumstances that have produced the current municipal regulatory approach to homelessness in the City of Melbourne, Victoria, and the ways in which visibly homeless people are policed through a micro-aesthetics of their presence in public space, which involves the monitoring of their bodily demeanour and their physical possessions. Our study contributes to and draws from a range of debates, including studies of the governmental conjunction of poverty and crime, analysis of the co-implication of law and spatiality, research on the criminalisation of homelessness and homeless people, and the burgeoning criminological interest in the significance of the visual field for our understandings of crime and criminality. This article recounts how homelessness, public space and questions of aesthetics have recently coalesced in debates about the regulation of homelessness in the public space of Melbourne’s city centre. It approaches the issues through comparative consideration of genres of municipal management frameworks in other jurisdictions, detailed textual consideration of the Protocol on Homelessness in the City of Melbourne and an empirical study of visible homelessness in the public places of central Melbourne
Grassland Management and Animal Product Quality
The expectations of consumers ultimately determine the specification of product quality; and grassland systems produce a wide range of animal-based products. Therefore, to provide focus, this paper deals only with food products that are destined for markets that exhibit strong discretionary choice. Quality expectations of consumers have traditionally been based on product attributes such as taste, freshness, nutritional value and appearance, but customer expectations are expanding to encompass food safety, environmental care, animal welfare and biotechnologies.
Grassland forages and their management influence the intrinsic sensory properties of food. A dairy products case study is presented, indicating that pasture species and their interaction with local environmental factors, and the methods of forage conservation, can influence the chemical composition of milk, its ability to be processed into butter or cheese, and the final sensory characteristics of the product. These effects may result directly from compounds originating in the forage (e.g. carotenoids, aromatic terpenes) or indirectly through forage-related changes in animal physiology and enzyme production. Knowledge of these influences and the strict control of the determining factors are key elements in the granting of Protected Denomination of Origin (DMO) status and the benefits that accrue from marketing strategies that depend on this status.
Animal feeding regimes also influence the attributes of meat. Pasture-grazed animals have harder and yellower carcass fat than grain-fed animals. The daily energy intake of pasture-grazed animals is also generally lower; therefore there is less intra-muscular marbling. In addition, glycogen levels tend to be more marginal, which can negatively interact with psychological stress to produce a greater incidence of high ultimate pH carcasses. High pH levels (\u3e 5.8) result in reduced tenderness, dark muscle and reduced shelf-life of fresh and chilled meats. Early identification of product quality variation is key to placing meat into the correct supply chain, and maximising the total value of the carcass. The positive and negative aspects of fatty acid profiles, phenol and indole compounds, and antioxidants originating from forages are discussed in respect of meat flavour and animal health.
Tight planning and management protocols for both plants and animals are crucial to achieving quality raw material from grassland systems. Unlike feedlot and barn-based enterprises, variation in forage quantity and quality can severely impact on animal performance, timeliness of supply and raw product constituents. Control of a forage-based system requires the setting of performance targets and on-going monitoring. Such measures can signal when the tactical use of specialist forages, or of high-quality supplements, will be of most value in maintaining target performance and animal health. Consistently supplying products with desired attributes, attending to animal welfare expectations and caring for environmental integrity will all be required if the credibility of ‘natural’ grassland products is to be sustained in the market-place. Controlled grazing of animals will be invaluable in meeting these multiple market demands
Hepatitis B among Pacific Islanders in Southern California: how is health information associated with screening and vaccination?
We measured Hepatitis B virus (HBV) transmission knowledge and self-reported screening/testing behavior among Pacific Islanders (Guamanians/Chamorros, Samoans, and Tongans) in Southern California. We also examined access and trust by Pacific Islanders of varying health information sources. We administered and analyzed survey data (N = 297), using a convenience sample in Los Angeles, Orange, and San Diego Counties in spring 2009. We found that while Pacific Islander respondents reported that they receive health information from physicians, and largely trust this source, information from and trust in physicians were not statistically significant in explaining whether respondents sought HBV screening or vaccination
Bethe Equations for a g_2 Model
We prove, using the coordinate Bethe ansatz, the exact solvability of a model
of three particles whose point-like interactions are determined by the root
system of g_2. The statistics of the wavefunction are left unspecified. Using
the properties of the Weyl group, we are also able to find Bethe equations. It
is notable that the method relies on a certain generalized version of the
well-known Yang-Baxter equation. A particular class of non-trivial solutions to
this equation emerges naturally.Comment: 10 pages, 3 figure
South African Guidelines Excellence (SAGE): Adopt, adapt, or contextualise?
Clinical practice guideline (CPG) activities must be planned carefully for efficient use of available resources and evidence-based implementation. De novo development of CPGs may sometimes ‘recreate the wheel’ and delay implementation. Three innovative alternatives to de novo CPG development (adopt, contextualise or adapt) are outlined, which have greater potential than de novo development to best use the limited available resources, personnel and time in settings such as South Africa
Social differentiation and spatial mixture in a transitional city - Kunming in southwest China
Socio-spatial segregation, and particularly racial and ethnic segregation, has been extensively studied in the Western context but is less researched for Chinese cities, particularly those in less developed regions. The city of Kunming in remote southwest China is characterized by a transition from a socialist manufacturing center to a free market service economy and the strong presence of a diversity of ethnic groups. Kunming provides an opportunity to examine the similarities and disparities in the socio-spatial landscape compared to well-developed cities in China and other post-socialist contexts as well as those in the West. In this paper, population census data at the community level from 2000 together with its spatial boundary data are used to create 39 demographic, educational, occupational and housing variables for 431 communities. Principal component analysis, hierarchical clustering and spatial segregation indicators are combined in order to identify, classify and analyse the spatial segregation of diverse social groups. The study finds that, unusually for Chinese cities, ethnic minority and gender are significant factors, and it demonstrates that both spatial mixture and social differentiation simultaneously characterize Kunming
Instantonic approach to triple well potential
By using a usual instanton method we obtain the energy splitting due to
quantum tunneling through the triple well barrier. It is shown that the term
related to the midpoint of the energy splitting in propagator is quite
different from that of double well case, in that it is proportional to the
algebraic average of the frequencies of the left and central wells.Comment: Revtex, 11 pages, Included one eps figur
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