753 research outputs found
Third Neighbor Correlators of Spin-1/2 Heisenberg Antiferromagnet
We exactly evaluate the third neighbor correlator and all
the possible non-zero correlators <S^{alpha}_j S^{beta}_{j+1} S^{gamma}_{j+2}
S^{delta}_{j+3}> of the spin-1/2 Heisenberg antiferromagnet in the ground
state without magnetic field. All the correlators are expressed in terms of
certain combinations of logarithm ln2, the Riemann zeta function zeta(3),
zeta(5) with rational coefficients. The results accurately coincide with the
numerical ones obtained by the density-matrix renormalization group method and
the numerical diagonalization.Comment: 4 page
Bacteriophages: their structural organisation and function
Viruses are infectious particles that exist in a huge variety of forms and infect practically all living systems: animals, plants, insects and bacteria. Viruses that infect and use bacterial resources are classified as bacteriophages (or phages) and represent the most abundant life form on Earth. A phage can be described as a specific type of nano-machine that is able to recognise its environment, find a host cell, start infection, self-assemble and safeguard its genome until the next cycle of replication is initiated. Remarkable results have been obtained by combining cryo-EM, X-ray analysis and bioinformatics in structural studies of these nano-machines. In this review we will describe results of structural studies of phages that uncover their organisation in different conformations, thus facilitating our understanding of the functional mechanisms in supramolecular assemblies and helping us understand the usage of phages in medical treatments. Currently, antibiotic resistance is an enormous challenge that we face. The tailed phages could be used in place of antibiotics due to their high specificity to host cells, but more knowledge of their organisation and function is required
Genotypes and phenotypes for apolipoprotein E and Alzheimer disease in the Honolulu-Asia aging study
BACKGROUND: The utility of apolipoprotein E (ApoE) type as an indicator of
genetic susceptibility to Alzheimer disease (AD) depends on the
reliability of typing. Although ApoE protein isoform phenotyping is
generally assumed equivalent to genotyping from DNA, phenotype-genotype
differences have been reported. METHODS: ApoE genotype and phenotype
results were examined for 3564 older (ages 71-93 years) Japanese-American
male participants of the Honolulu-Asia Aging Study, an ongoing
population-based study of aging and dementia. RESULTS: Both methods
demonstrated similar associations of ApoE type with AD: a direct
association with ApoE4 and a less dramatic inverse association ApoE2.
Advanced age did not appear to influence the ApoE4-AD association. The
association with AD among ApoE4 homozygotes [odds ratio (OR) = 14.7] was
higher than expected based on an observed OR of 2.0 in heterozygotes.
Phenotype-genotype nonconcordance was more frequent for ApoE2 than for
ApoE4. The ApoE2 phenotype occurred at a frequency of 7.9% vs a genotype
frequency of 4.9%, corresponding to a probability of 56% that an
individual with ApoE2 phenotype had the same genotype. CONCLUSIONS:
Whereas E4 and E2 phenotypes and genotypes were comparably associated with
AD, neither method would be expected to substantially improve the
efficiency of case finding in the context of population screening beyond
prediction based on age and education. Nonconcordance of phenotype and
genotype was substantial for E2 and modest for E4 in this population. The
ApoE4-AD association was independent of age
Gravitational Mesoscopic Constraints in Cosmological Dark Matter Halos
We present an analysis of the behaviour of the `coarse-grained'
(`mesoscopic') rank partitioning of the mean energy of collections of particles
composing virialized dark matter halos in a Lambda-CDM cosmological simulation.
We find evidence that rank preservation depends on halo mass, in the sense that
more massive halos show more rank preservation than less massive ones. We find
that the most massive halos obey Arnold's theorem (on the ordering of the
characteristic frequencies of the system) more frequently than less massive
halos. This method may be useful to evaluate the coarse-graining level (minimum
number of particles per energy cell) necessary to reasonably measure signatures
of `mesoscopic' rank orderings in a gravitational system.Comment: LaTeX, 15 pages, 3 figures. Accepted for publication in Celestial
Mechanics and Dynamical Astronomy Journa
Business Process Modeling: Defining Domain Specific Modeling Languages by Use of UML Profiles
What can local authorities do to improve the social care-related quality of life of older adults living at home? Evidence from the Adult Social Care Survey
Local authorities spend considerable resources on social care at home for older adults. Given the expected growth in the population of older adults and budget cuts on local government, it is important to find efficient ways of maintaining and improving the quality of life of older adults. The ageing in place literature suggests that policies in other functions of local authorities may have a significant role to play. This study aims to examine the associations between social care-related quality of life (SCRQoL) in older adults and three potential policy targets for local authorities: (i) accessibility of information and advice, (ii) design of the home and (iii) accessibility of the local area. We used cross-sectional data from the English national Adult Social Care Survey (ASCS) 2010/2011 on service users aged 65 years and older and living at home (N=29,935). To examine the association between SCRQoL, as measured by the ASCOT, and three single-item questions about accessibility of information, design of the home and accessibility of the local area, we estimate linear and quantile regression models. After adjusting for physical and mental health factors and other confounders our findings indicate that SCRQoL is significantly lower for older adults who find it more difficult to find information and advice, for those who report that their home design is inappropriate for their needs and for those who find it more difficult to get around their local area. In addition, these three variables are as strongly associated with SCRQoL as physical and mental health factors. We conclude that in seeking to find ways to maintain and improve the quality of life of social care users living at home, local authorities could look more broadly across their responsibilities. Further research is required to explore the cost-effectiveness of these options compared to standard social care services
Neutralino properties in the light of a further indication of an annual modulation effect in WIMP direct search
We demonstrate that the further indication of a possible annual modulation
effect, singled out by the DAMA/NaI experiment for WIMP direct detection, is
widely compatible with an interpretation in terms of a relic neutralino as the
major component of dark matter in the Universe. We discuss the supersymmetric
features of this neutralino in the Minimal Supersymmetric extension of the
Standard Model (MSSM) and their implications for searches at accelerators.Comment: 15 pages, ReVTeX, 9 figures (included as PS files
Studies on two stage sludge digestion, 1928-29
At head of title: State of Illinois. Department of registration and education. Division of the state Water survey."Bulletins of the state water survey": 1 leaf at end."Literature cited": p. 92.Enumeration continues from preceding title
Timing of surgery following neoadjuvant chemoradiotherapy in locally advanced rectal cancer – A comparison of magnetic resonance imaging at two time points and histopathological responses
Genetic variation at MECOM, TERT, JAK2 and HBS1L-MYB predisposes to myeloproliferative neoplasms
Clonal proliferation in myeloproliferative neoplasms (MPN) is driven by somatic mutations in JAK2, CALR or MPL, but the contribution of inherited factors is poorly characterized. Using a three-stage genome-wide association study of 3,437 MPN cases and 10,083 controls, we identify two SNPs with genome-wide significance in JAK2V617F-negative MPN: rs12339666 (JAK2; meta-analysis P=1.27 × 10−10) and rs2201862 (MECOM; meta-analysis P=1.96 × 10−9). Two additional SNPs, rs2736100 (TERT) and rs9376092 (HBS1L/MYB), achieve genome-wide significance when including JAK2V617F-positive cases. rs9376092 has a stronger effect in JAK2V617F-negative cases with CALR and/or MPL mutations (Breslow–Day P=4.5 × 10−7), whereas in JAK2V617F-positive cases rs9376092 associates with essential thrombocythemia (ET) rather than polycythemia vera (allelic χ2 P=7.3 × 10−7). Reduced MYB expression, previously linked to development of an ET-like disease in model systems, associates with rs9376092 in normal myeloid cells. These findings demonstrate that multiple germline variants predispose to MPN and link constitutional differences in MYB expression to disease phenotype
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